MCCQE Sample Questions Answers

This case describes classic signs of delusional parasitosis (also known as Morgellons syndrome).However, the presence of widespread crusted lesions raises suspicion for crusted scabies, particularly in older adults. Crusted scabies may be misinterpreted as chronic dermatitis or psychocutaneous disorder. The most effective treatment is oral ivermectin.

Toronto Notes 2023 – Dermatology:

“Crusted scabies presents as widespread hyperkeratotic plaques with crusting. First-line treatment is oral ivermectin, often with topical permethrin.”

MCCQE1 Objectives (Medicine > Dermatology > 23-1):

“Candidates must recognize presentations of ectoparasitic infections, including scabies, and provide appropriate treatment.”

Permethrin (B) is for typical scabies, but crusted scabies often requires systemic ivermectin due to severity and spread.

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Comprehensive and Detailed Explanation:

The image and clinical history are consistent with physiologic pubertal gynecomastia, which is common in adolescent boys. It usually resolves spontaneously within 6 months to 2 years and does not require investigation unless other signs of endocrine pathology are present.

Toronto Notes 2023 – Pediatrics / Endocrinology:

“Pubertal gynecomastia is benign, self-limited, and common in adolescent males. No further investigation is needed in the absence of systemic signs.”

MCCQE1 Objectives (Pediatrics > 77-2: Endocrine Disorders):

“Candidates must differentiate physiologic gynecomastia from pathologic causes based on history and physical exam.”

Other tests (A–C, E) are unnecessary unless there are red flags (e.g., testicular mass, rapid progression, neurological symptoms).

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In pediatric trauma, inability to void with perineal bruising raises concern for urethral injury or urinary retention due to soft tissue swelling. The most immediate step is to attempt bladder catheterization. If unsuccessful, consult gynecology or urology urgently to avoid bladder overdistension.

Toronto Notes 2023 – Pediatrics, Genitourinary Trauma:

“In females, perineal trauma can lead to urinary retention due to labial hematomas or urethral injury. If catheterization is difficult, consult gynecology or urology for assistance.”

MCCQE1 Objectives – Pediatrics > Trauma and Emergency Care:

“Candidates must recognize when specialist consultation is required in pediatric genitourinary trauma, especially in cases of failed catheterization.”

Options B and D delay necessary care. Coagulation studies (C) may be considered if bleeding is unexplained. Abuse assessment (E) may be necessary later but does not address immediate retention.

A mood journal is a structured tool that allows the patient to record mood fluctuations, triggers, and timing. It is particularly helpful in identifying mood disorders such as premenstrual dysphoric disorder, bipolar disorder, or cyclothymia.

Toronto Notes 2023 – Psychiatry, Mood Disorders:

“Mood diaries are useful in identifying temporal patterns, such as menstrual cycle–linked mood changes, and in distinguishing between affective disorders.”

MCCQE1 Objectives – Psychiatry > Diagnostic Evaluation:

“Candidates should use clinical tools such as symptom diaries to assist in establishing the pattern and nature of psychiatric symptoms.”

Personality testing (A) is not first-line. Urine drug screen (B) is only indicated with suspicion of substance use. Lorazepam (D) treats symptoms, not diagnosis. Interviewing the boyfriend (E) may help, but only as a supplement to direct observation and self-report.

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Scaphoid fractures are often radiographically occult on initial presentation and can present later with persistent pain and swelling in the anatomical snuffbox. They typically occur following a fall on an outstretched hand. If missed, they can lead to avascular necrosis.

Toronto Notes 2023 – Orthopedics, Wrist Injuries:

“Scaphoid fractures are the most common carpal fractures. X-rays may be negative early, so high suspicion requires immobilization and repeat imaging after 10–14 days.”

MCCQE1 Objectives – Surgery > Musculoskeletal Trauma:

“Candidates must recognize that some fractures, such as scaphoid, may not appear on initial imaging but require clinical suspicion and follow-up imaging or immobilization.”

Other options (B and C) are less likely without radiographic evidence. De Quervain tenosynovitis (D) presents with radial wrist pain unrelated to trauma and worsens with thumb movement.

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Chronic mesenteric ischemia (also known as “intestinal angina”) presents as postprandial abdominal pain, leading to food avoidance and significant weight loss. GI exams may be normal. Imaging (e.g., angiography or CT angio) confirms the diagnosis.

Toronto Notes 2023 – Gastroenterology, “Chronic Mesenteric Ischemia”:

“Classic triad: postprandial abdominal pain, weight loss, and food aversion. Physical exam and GI series may be normal.”

MCCQE1 Objectives (Gastroenterology > 47-1: Abdominal Pain):

“Candidates must suspect mesenteric ischemia in older adults with risk factors and postprandial pain leading to weight loss.”

PUD (A) usually causes epigastric pain relieved by food. Cholelithiasis (B) causes RUQ pain. Colon cancer (D) presents with altered bowel habits or bleeding. Mesenteric adenitis (C) occurs in younger patients, often with infection.

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This patient has secondary amenorrhea, infertility, and a history of multiple uterine curettages, which strongly points toward Asherman syndrome (intrauterine adhesions or synechiae). The hysterosalpingogram shows an obliterated uterine cavity and no tubal dye spill—classic for intrauterine synechiae. Her midluteal progesterone level is normal, indicating ovulation.

Toronto Notes 2023 – Gynecology, “Infertility” section:

“Asherman syndrome results from intrauterine adhesions due to curettage, leading to amenorrhea and infertility. HSG shows an obliterated or irregular uterine cavity.”

MCCQE1 Objectives (Gynecology > 82-1: Infertility):

“Candidates should evaluate secondary amenorrhea and interpret imaging such as hysterosalpingogram in the diagnosis of intrauterine abnormalities.”

Other options are ruled out by the presence of normal ovulation (rules out hypothalamic and PCOS) and by imaging (not suggestive of fibroids or perimenopause).

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Refusing care based on sexual orientation constitutes discrimination under the Canadian Charter of Rights and Freedoms and violates professional standards. Physicians must not deny care based on personal bias or prejudice.

Toronto Notes 2023 – ELOM, Equity in Care and Professionalism:

“Denying care based on sexual orientation violates both human rights legislation and professional obligations. Physicians must ensure equitable access for all patients.”

MCCQE1 Objectives – ELOM > Professionalism and Patient Rights:

“Candidates must act in accordance with patients’ rights to equitable, non-discriminatory access to care regardless of race, gender, or sexual orientation.”

Referral (Option B) does not excuse discriminatory refusal. Personal discomfort or inexperience (Options D and E) do not justify discrimination.

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Comprehensive and Detailed Explanation:

Middle-aged to older men with social isolation and substance use disorders (especially alcohol) are among the highest-risk groups for completed suicide. They are less likely to seek help and often use more lethal methods.

Toronto Notes 2023 – Psychiatry, “Suicide Risk Assessment”:

“High-risk demographics include older men, social isolation, comorbid alcohol use, and chronic illness. These patients have the highest rates of completed suicide.”

MCCQE1 Objectives (Psychiatry > 71-1: Suicide Risk):

“Candidates must recognize epidemiologic risk factors for completed suicide, including demographics and comorbidities.”

Although women and youth have higher rates of suicidal ideation and attempts, men over 50 have the highest completion rates.

When an error in the system is identified (e.g., test result not properly followed up), the most responsible approach is to analyze and improve internal clinic processes. Patient safety depends on reliable result tracking systems.

Toronto Notes 2023 – ELOM, “Medical Errors and Quality Improvement” Section:

“When an error or near miss is identified, root cause analysis and system-level interventions are required to prevent recurrence. Blaming the patient or others without review of internal processes is inappropriate.”

MCCQE1 Objectives (ELOM > 99-1: Medical Error and Disclosure):

“Candidates must recognize the importance of continuous quality improvement in health care. System-level changes should be implemented when safety lapses occur.”

Option A shifts responsibility improperly onto the patient. Option C deflects blame without assessing one’s own clinic. Option D minimizes the error and does not lead to improvement.

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This patient is experiencing social instability (homelessness, job loss) likely contributing to poorly controlled diabetes. Before investigating or prescribing further, it is essential to address his ability to afford and manage self-monitoring and insulin.

Toronto Notes 2023 – Endocrinology, Diabetes:

“Social determinants such as housing insecurity and financial barriers significantly affect diabetes self-management. Addressing access to glucose monitoring and insulin is critical.”

MCCQE1 Objectives – Internal Medicine > Chronic Disease Management:

“Candidates must assess barriers to effective disease control, including financial and psychosocial limitations.”

Antidepressants (B) may be helpful later if depression is suspected. Thyroid testing (C) is not the priority. A dietitian (D) may help long-term, but immediate access and adherence are more urgent.

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This adolescent exhibited acute suicidal behavior (attempted to jump out of a window), which is a psychiatric emergency. Regardless of intoxication or cause, such behavior mandates a safety-first approach: involuntary psychiatric assessment and protection from self-harm.

Toronto Notes 2023 – Psychiatry, “Suicide and Crisis Intervention” Section:

“Involuntary psychiatric admission is indicated when a patient poses a danger to themselves or others. Suicidal ideation or attempts require immediate evaluation and monitoring.”

MCCQE1 Objectives (Psychiatry > 79-2: Suicide and Risk Management):

“Candidates must identify suicidal behavior and initiate appropriate action, including involuntary admission if necessary for safety.”

Observation (B) may miss the window for action. Parents (A) should be contacted but are not a substitute for admission. Chlordiazepoxide (C) is not first-line in this scenario.

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This constellation of features—hypotonia, macroglossia, brachycephaly, single palmar crease, short broad hands with clinodactyly—is classic for Down syndrome (Trisomy 21).

Toronto Notes 2023 – Pediatrics, “Genetic Syndromes”:

“Trisomy 21 features include hypotonia, upslanting palpebral fissures, epicanthic folds, flat nasal bridge, brachycephaly, macroglossia, single palmar crease, and clinodactyly.”

MCCQE1 Objectives (Pediatrics > 78-3: Congenital and Genetic Disorders):

“Candidates must recognize key dysmorphic features associated with common genetic syndromes including Trisomy 21.”

Prader-Willi and congenital hypothyroidism may have hypotonia but lack the full phenotypic pattern. Turner syndrome is seen in females with short stature and webbed neck. Fetal alcohol syndrome presents with smooth philtrum and microcephaly.

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Chlamydia trachomatis is the most common cause of cervicitis in young sexually active women and frequently presents with dysuria, dyspareunia, intermenstrual bleeding, and a normal vulvovaginal exam. It may be asymptomatic or have subtle signs and often affects the endocervix.

Toronto Notes 2023 – Gynecology, “Sexually Transmitted Infections” Section:

“Chlamydia is the most common bacterial STI. Symptoms may include intermenstrual bleeding, postcoital bleeding, dyspareunia, mucopurulent cervical discharge, and dysuria. The vulva and vagina may appear normal.”

MCCQE1 Objectives (Obstetrics and Gynecology > 82-1: Abnormal Uterine Bleeding):

“Candidates should evaluate STI-related cervicitis as a common cause of postcoital and intermenstrual bleeding in young women.”

Other options:

A. Actinomyces israelii is associated with IUD use, not relevant here.

B. Herpes simplex virus usually presents with painful ulcerations, not abnormal bleeding.

C. Treponema pallidum (syphilis) causes painless ulcers or systemic symptoms in later stages.

D. HPV causes warts or asymptomatic cervical dysplasia, not acute symptoms.

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Comprehensive and Detailed Explanation:

Decreased libido in elderly patients can be multifactorial, but depression is a common and important cause that must be ruled out before hormone therapy or other steps. A proper mental health screen should precede further interventions.

Toronto Notes 2023 – Psychiatry / Geriatrics:

“In elderly men, reduced libido may be linked to depression, medical illness, or medications. Depression screening is essential.”

MCCQE1 Objectives (Psychiatry > 71-1: Mood Disorders / Sexual Health):

“Candidates must consider depression as a common cause of decreased libido and assess accordingly before initiating hormone therapy.”

Testosterone testing (D) may follow. Prescribing (C) is premature. Couples counselling (B) may help if interpersonal issues are identified. Interviewing together (A) may inhibit disclosure.

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Comprehensive and Detailed Explanation:

Ginger is a first-line, evidence-based non-pharmacologic treatment for nausea and vomiting in pregnancy. It's well tolerated and effective. Addressing nausea will help her resume vitamin use and reduce distress.

Toronto Notes 2023 – Obstetrics, “Nausea and Vomiting in Pregnancy”:

“Ginger 250 mg four times daily is safe and effective for mild to moderate nausea.”

MCCQE1 Objectives (Obstetrics > 80-1: Early Pregnancy Management):

“Candidates must treat nausea and vomiting in pregnancy using safe and effective options.”

Folic acid alone (A) is less effective than a full prenatal vitamin. B may help, but nausea should be addressed first. C lacks empathy for her symptoms. D (cannabinoids) is not recommended in pregnancy.

Comprehensive and Detailed Explanation:

Epidural analgesia is associated with increased maternal intrapartum fever due to non-infectious(neurogenic) thermoregulation impairment. This is a well-known phenomenon in laboring women.

Toronto Notes 2023 – Obstetrics / Anesthesia:

“Epidural analgesia increases risk of intrapartum fever by up to 20% via non-infectious mechanisms.”

MCCQE1 Objectives (Obstetrics > 80-5: Intrapartum Care):

“Candidates must recognize risk factors for intrapartum complications, including effects of epidural use.”

Multiparity (A), precipitous labor (B), and maternal age (C) are not established risk factors for intrapartum fever.

Fibrocystic change is the most common benign breast condition in women of reproductive age. It typically presents with diffuse nodularity or "lumpy" areas, especially in the upper outer quadrant, and varies with the menstrual cycle. No dominant mass or systemic signs are expected.

Toronto Notes 2023 – Gynecology, “Benign Breast Conditions”:

“Fibrocystic changes often present with bilateral or unilateral nodularity, most commonly in the upper outer quadrants, without discrete masses.”

MCCQE1 Objectives (Gynecology > 81-1: Breast Conditions):

“Candidates must differentiate benign breast conditions from malignant ones based on presentation and physical exam findings.”

Paget disease (B) presents with nipple changes. Intraductal carcinoma (C) typically shows a discrete mass or suspicious features. Phyllodes tumours are usually well-circumscribed. Mastitis (E) is inflammatory and associated with erythema, fever, and tenderness.

This patient’s headache is consistent with tension-type or stress-related headache. The symptoms are mild, responsive to over-the-counter medications, and without red flags (neurologic signs, worsening pattern, nocturnal pain). Reassurance is appropriate.

Toronto Notes 2023 – Neurology, “Headache” Section:

“In the absence of red flags (e.g., sudden onset, focal deficits, age >50, worsening pattern), reassurance is the best course. Tension headaches are often related to stress and improve with lifestyle modification and simple analgesia.”

MCCQE1 Objectives (Internal Medicine > 76-6: Neurologic Symptoms):

“Candidates should recognize benign headache patterns and avoid unnecessary investigations.”

CT head (B) is not indicated. Stronger analgesics (D) may cause rebound headache. Specialist or psychiatric referrals (A, E) are premature.

Comprehensive and Detailed Explanation:

The patient presents with classic symptoms of schizophrenia: delusions, hallucinations, social withdrawal, and disorganized appearance. The first-line treatment is antipsychotic medication—risperidone is a well-tolerated option among second-generation antipsychotics.

Toronto Notes 2023 – Psychiatry, “Schizophrenia”:

“Schizophrenia is treated with second-generation antipsychotics such as risperidone. These reduce positive symptoms like delusions and hallucinations.”

MCCQE1 Objectives (Psychiatry > 71-3: Psychotic Disorders):

“Candidates must recognize and manage schizophrenia with antipsychotics and distinguish from other mood or personality disorders.”

CBT (E) is supportive but not first-line. ECT (A) is used for severe depression or catatonia. Valproic acid (C) and carbamazepine (D) are mood stabilizers, not first-line for schizophrenia.

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Comprehensive and Detailed Explanation:

This patient demonstrates excellent exercise tolerance (17 METs) and no ischemic changes or exertional symptoms, which makes cardiac ischemia unlikely. However, the hypertensive response to exercise (BP >190 systolic) indicates masked or latent hypertension. This should be managed proactively, typically starting with a thiazide.

Toronto Notes 2023 – Cardiology:

“An exaggerated hypertensive response during exercise is predictive of future hypertension. Treatment with antihypertensive agents such as thiazides may be warranted.”

MCCQE1 Objectives (Internal Medicine > 31-1: Hypertension and Risk Management):

“Candidates must identify abnormal BP responses to exercise and initiate appropriate treatment.”

Reassurance alone (A) ignores the hypertensive response. Catheterization (C) and beta-blockers (D) are unnecessary without ischemia. Advising against exercise (B) is counterproductive in a young, otherwise healthy patient.

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Comprehensive and Detailed Explanation:

Rapid progression of pain out of proportion to exam, systemic symptoms (anxiety), and skinchanges without major swelling are classic for necrotizing fasciitis—a surgical emergency. Discoloration and extreme tenderness should raise immediate concern.

Toronto Notes 2023 – Emergency Medicine / Surgery:

“Necrotizing fasciitis presents with severe pain, systemic toxicity, rapid progression, and early skin changes (discoloration). Pain out of proportion is a key clue.”

MCCQE1 Objectives (Emergency Medicine > 51-1: Soft Tissue Infections):

“Candidates must recognize necrotizing fasciitis and initiate urgent surgical consultation.”

Plantaris rupture (A) is benign and localized. DVT (B) is more gradual and often with swelling. Cellulitis (C) progresses more slowly and is less painful. Baker’s cyst (D) causes posterior knee pain, not severe systemic illness.

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In Canada and in most jurisdictions internationally, physicians have a professional and in some cases legal obligation to provide emergency assistance. Documentation should be done in your own records afterward. Aviation laws and Good Samaritan protections offer liability coverage for health professionals acting in good faith.

Toronto Notes 2023 – ELOM, “Physician Obligations and Medical-Legal Responsibility”:

“Physicians should respond to in-flight or public emergencies when capable. Documentation should be completed after the event, and liability is protected under Good Samaritan laws.”

MCCQE1 Objectives (ELOM > Professionalism > 90-1):

“Candidates must demonstrate appropriate professional behavior, including willingness to assist in emergencies and understanding of legal protections.”

Avoiding assistance (A), or placing conditional barriers (D), is unethical and inappropriate.

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Comprehensive and Detailed Explanation:

The Zika virus can be sexually transmitted and poses a serious risk of congenital Zika syndrome if infection occurs during pregnancy. The CDC and WHO recommend that couples delay conception for at least 3 months after potential male exposure due to the virus's persistence in semen.

Toronto Notes 2023 – Infectious Diseases / Travel Medicine:

“Zika virus may persist in semen for weeks. Couples should delay conception for 3 months after male exposure, even if asymptomatic.”

MCCQE1 Objectives (Public Health > 65-3: Travel Medicine and Reproductive Health):

“Candidates must counsel appropriately regarding risks of Zika in conception and apply current public health recommendations.”

Testing (B) is not reliable for asymptomatic individuals. Antivirals (E) are ineffective. Condoms (D) do reduce risk. Specialist referral (A) is not needed in most cases with no complications.

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This patient is competent and capable of making his own health decisions. A DNR order and naming a substitute decision-maker apply only when a patient lacks capacity. The next step is to discuss the suspected diagnosis with the patient and explore his preferences.

Toronto Notes 2023 – ELOM, Consent and Capacity:

“Competent patients retain full decision-making authority. Substitute decision-makers are only engaged when the patient lacks capacity. DNR applies to resuscitation, not other medical decisions.”

MCCQE1 Objectives – ELOM > Capacity, Consent, Advance Directives:

“Candidates must recognize that capable patients should be directly involved in decisions. Substitute decision-makers are not invoked unless the patient is incapable.”

Option A implies a breach of confidentiality without permission. Option C is premature. Option D bypasses informed consent. Option E misinterprets the DNR’s scope.

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Referrals should be medically indicated. Physicians are not obligated to refer simply because a patient (or colleague) requests it, especially when it may lead to unnecessary care. The ethical and appropriate action is to explain your medical reasoning and decline an unwarranted referral.

Toronto Notes 2023 – ELOM, “Professionalism and Resource Stewardship” Section:

“Physicians have a responsibility to act as gatekeepers to specialist services and should not refer patients when criteria are not met. Explaining the reasoning and declining the request respectfully is appropriate.”

MCCQE1 Objectives (ELOM > 99-1: Professionalism and Clinical Judgment):

“Candidates must demonstrate ethical reasoning in managing requests for unwarranted interventions.”

Involving the emergency department (B) or another physician (C) is not appropriate unless there's a true conflict of interest. Calling a consultant (E) may be unnecessary if no medical reason exists.

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Comprehensive and Detailed Explanation:

Complex endometrial hyperplasia with atypia carries a high risk of progression to or concurrent endometrial carcinoma. Definitive management in postmenopausal women is total hysterectomy with bilateral salpingo-oophorectomy.

Toronto Notes 2023 – Gynecology, Abnormal Uterine Bleeding:

“Endometrial hyperplasia with atypia in postmenopausal women is best managed surgically due to the risk of malignancy.”

MCCQE1 Objectives – Gynecology > Postmenopausal Bleeding:

“Candidates should identify endometrial hyperplasia with atypia as an indication for hysterectomy in appropriate patients.”

Ablation (A) is contraindicated. Progesterone (B) is used for non-atypical hyperplasia. D&C (C) and hysteroscopy (D) are diagnostic but not definitive.

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Anaphylaxis requires immediate administration of epinephrine via the intramuscular (IM) route, typically in the lateral thigh. This route provides the fastest and most reliable absorption for emergency treatment.

Toronto Notes 2023 – Pediatrics, Anaphylaxis:

“Epinephrine 0.01 mg/kg IM is the first-line treatment for anaphylaxis. The intramuscular route provides the most rapid and safe absorption in emergencies.”

MCCQE1 Objectives – Pediatrics > Allergy and Immunology:

“Candidates must know the emergency management of anaphylaxis, including proper dosage and intramuscular administration of epinephrine.”

IV administration (A) is reserved for critical care settings. Subcutaneous (C) and intranasal/inhaled routes (D, E) are ineffective in anaphylaxis.

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Sudden onset dyspnea and pleuritic chest pain in a postoperative patient with tachypnea and clear lung fields are classic features of a pulmonary embolism (PE). Recent orthopedic surgery significantly increases VTE risk. Clear lungs on auscultation support this over pneumonia or CHF.

Toronto Notes 2023 – Respiratory, “Pulmonary Embolism”:

“Presentation includes sudden dyspnea, pleuritic chest pain, and tachypnea. Risk factors include recent surgery and immobilization. Examination often reveals clear chest auscultation.”

MCCQE1 Objectives (Internal Medicine > Cardiopulmonary > 44-1):

“Candidates must recognize PE in patients with risk factors (e.g., surgery) and classic features and initiate appropriate diagnosis and management.”

Fat embolism (B) usually presents with petechiae, neurologic symptoms, and occurs within 24–72 hours post-op. Cholesterol emboli (E) are more chronic and systemic.

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Comprehensive and Detailed Explanation:

At 20 weeks’ gestation, the uterine fundus typically reaches the umbilicus. If the fundal height is lower than expected at a stated gestational age of 26 weeks, the most likely explanation—especially with no prior care—is a dating error.

Toronto Notes 2023 – Obstetrics:

“Fundal height at the umbilicus corresponds to ~20 weeks. In women lacking early prenatal care, dating errors are common causes of fundal height discrepancy.”

MCCQE1 Objectives (Obstetrics > 80-3: Routine Antenatal Care):

“Candidates must interpret fundal height and reconcile discrepancies with gestational age.”

IUGR and oligohydramnios are possible but require imaging confirmation. Bicornuate uterus may cause fundal shape anomalies but not significant dating discrepancy. A mole (D) would increase, not decrease, size.

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Comprehensive and Detailed Explanation:

Given his age and a first-degree relative with colon cancer diagnosed before age 60, this patient meets criteria for early colon cancer screening. Colonoscopy is the gold standard for both screening and diagnosis in this context.

Toronto Notes 2023 – Gastroenterology, “Colorectal Cancer Screening”:

“Patients with a first-degree relative diagnosed with colorectal cancer before age 60 should begin screening at age 40, or 10 years before the relative’s diagnosis. Colonoscopy is the preferred method.”

MCCQE1 Objectives (Population Health > Preventive Screening > 63-1):

“Candidates must apply colorectal cancer screening guidelines and select appropriate tests based on risk level.”

FIT (A) is for average-risk screening. MRI (B) and CT colonography (E) are secondary. Barium enema (D) is outdated.

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The symptoms — visual hallucinations, attention deficits, gait instability — suggest dementia with Lewy bodies (DLB), which may show bilateral frontal or parietal atrophy on imaging.

Toronto Notes 2023 – Psychiatry, Neurocognitive Disorders:

“DLB presents with fluctuating cognition, visual hallucinations, parkinsonism, and attention deficits. Imaging may show frontal or parietal atrophy but is not always specific.”

MCCQE1 Objectives – Psychiatry > Neurocognitive Disorders:

“Candidates must recognize the characteristic features of DLB and support diagnosis with imaging when appropriate.”

Cerebellar atrophy (A) is linked to ataxia but not hallucinations. Subdural hematoma (B) causes abrupt decline. Mediotemporal atrophy (D) is typical of Alzheimer’s. Option E is incorrect — imaging can support the diagnosis.

This presentation is classic for an undiagnosed pheochromocytoma, which causes episodic or crisis-level hypertension due to excess catecholamines. Anesthesia or surgical manipulation can trigger massive catecholamine release, leading to hypertensive crisis. Phentolamine, an alpha-blocker, is the appropriate treatment.

Toronto Notes 2023 – Endocrinology, Pheochromocytoma:

“Pheochromocytomas may precipitate hypertensive crises during surgery. Elevated plasma catecholamines and urinary metanephrines confirm diagnosis.”

MCCQE1 Objectives – Internal Medicine > Endocrinology:

“Candidates should suspect pheochromocytoma in perioperative hypertensive crises and confirm with plasma or urine catecholamines/metanephrines.”

Low metanephrines (E) would argue against pheochromocytoma. TSH (A), cortisol (D), and renin (C) are unrelated to acute intraoperative hypertensive episodes of this nature.

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Comprehensive and Detailed Explanation:

The authority to license and regulate physicians to practise medicine is held by the medical regulatory colleges in each province or territory (e.g., CPSO in Ontario, CPSBC in BC).

MCC Objectives (ELOM > 90-1: Medical Regulation in Canada):

“Licensure to practise medicine is granted by the provincial or territorial medical regulatory authority.”

Toronto Notes 2023 – Ethics and Canadian Health Care System:

“Medical regulatory colleges determine physician licensure and discipline in each jurisdiction.”

The CFPC/RCPSC (C) certify physicians, not license them. Ministries of Health (A) oversee health policy, not licensing. Associations (E) advocate for physicians but do not regulate. Hospital boards (B) grant privileges, not licenses.

Comprehensive and Detailed Explanation:

Opioid-induced constipation is best managed with stimulant laxatives like senna or bisacodyl. Stool softeners such as docusate are insufficient as monotherapy. Senna stimulates peristalsis, making it more effective.

Toronto Notes 2023 – Palliative Care:

“Opioid-induced constipation requires stimulant laxatives such as senna. Stool softeners alone are not adequate.”

MCCQE1 Objectives (Palliative Care > 92-1: Symptom Management):

“Candidates must treat opioid-related side effects appropriately, including use of stimulant laxatives for constipation.”

Bulk agents (C) can worsen symptoms. Reducing morphine (D) may compromise pain control. Activity (E) helps but is insufficient as first-line management.

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The patient shows signs of herpes labialis (HSV-1), which can transmit genital herpes via oral sex. This poses a risk to the fetus if maternal infection occurs during pregnancy, especially near delivery. Preventing new genital HSV infection during pregnancy is critical.

Toronto Notes 2023 – Obstetrics:

“HSV-1 can cause genital herpes via oral-genital transmission. Avoid oral sex during outbreaks in pregnancy to prevent primary maternal infection.”

MCCQE1 Objectives (Obstetrics > 80-3: Infectious Disease in Pregnancy):

“Candidates must understand the importance of preventing new HSV infection during pregnancy and counsel appropriately.”

Culture (A) is not useful unless symptomatic. Serology (B) is not needed in this context. Cesarean (D) is not indicated unless active genital lesions at delivery. Acyclovir (C) is for infected mothers or near delivery.

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In a case-control study, participants are selected based on outcome (e.g., presence or absence of neonatal jaundice), and then past exposures are evaluated. This is consistent with the described methodology.

Toronto Notes 2023 – Epidemiology, “Study Designs”:

“Case-control studies start with the outcome and look backward to assess exposures. They are efficient for studying rare conditions or those with long latency.”

MCCQE1 Objectives (Population Health > 65-2: Epidemiology and Study Design):

“Candidates must distinguish between common study designs and recognize the correct classification based on study structure.”

Cross-sectional studies (A) assess exposure and outcome at the same time. Cohort studies (C) begin with exposure and follow forward. Clinical trials (D) are interventional. Ecological studies (E) analyze population-level data.

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Comprehensive and Detailed Explanation:

Hyponatremia in a patient with lung cancer and euvolemia strongly suggests syndrome of inappropriate antidiuretic hormone secretion (SIADH), especially from small cell carcinoma. Serum osmolality is the best initial test to confirm hypotonic hyponatremia and distinguish true hyponatremia from pseudohyponatremia or other causes.

Toronto Notes 2023 – Endocrinology, “Hyponatremia”:

“Serum osmolality helps classify hyponatremia as hypotonic, isotonic, or hypertonic. SIADH typically causes hypotonic hyponatremia in euvolemic patients.”

MCCQE1 Objectives (Endocrinology > 37-1: Electrolyte Disorders):

“Candidates must evaluate the type and cause of hyponatremia using clinical status and laboratory tests including serum osmolality.”

Urine sodium (B) is useful after confirming hypotonicity. PTHrP (E) is associated with hypercalcemia of malignancy, not hyponatremia. Urinalysis (A) and CrCl (D) are less directly informative.

Comprehensive and Detailed Explanation:

An estimated fetal weight below the 5th percentile at 30 weeks is concerning for intrauterine growth restriction (IUGR). This warrants prompt evaluation of fetal well-being via biophysical profile and Doppler assessment. The patient should be referred for further fetal assessment immediately to rule out placental insufficiency or other complications.

Toronto Notes 2023 – Obstetrics, “Fetal Growth Restriction”:

“EFW < 10th percentile, especially < 5th, warrants further evaluation including Doppler studies and biophysical profile. Immediate assessment is warranted to determine fetal well-being.”

MCCQE1 Objectives (Obstetrics > 80-4: Antepartum Surveillance):

“Candidates must initiate urgent assessment in cases of abnormal fetal growth to reduce perinatal morbidity.”

Delaying care (B) is inappropriate. Reassurance (A) is unsafe. ASA (D) is preventative, not corrective. Doppler (E) is important but should be coordinated through obstetrical triage.

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This presentation describesnormal developmental dysfluency, which typically occurs between ages 2–5 and often worsens duringtimes of stress or change, such as a new sibling. It is characterized byword repetitionand does not require intervention unless it persists >6 months, worsens, or causes distress.

Toronto Notes 2023 – Pediatrics, "Developmental and Behavioral Pediatrics" Section:

“Developmental stuttering is common between 2–5 years and often resolves without intervention. Reassurance is appropriate unless there are signs of persistent or severe stuttering, secondary behaviors, or parental concern.”

MCCQE1 Objectives (Pediatrics > 78-1: Development and Behavior):

“Candidates must recognize typical patterns of developmental speech dysfluency and differentiate them from pathological speech disorders. Observation and reassurance are often the appropriate initial step.”

Because the child is otherwise developing normally and the onset coincides with a known psychosocial stressor,reassuranceis the most appropriate step. Formal speech or behavioral therapy is not indicated at this time.

When encountering vaccine hesitancy, the first and most effective step is to open a non-judgmental conversation and explore the patient’s reasons. This helps build trust and tailor subsequent education and counseling.

Toronto Notes 2023 – Public Health and Preventive Medicine, Immunization:

“Addressing vaccine hesitancy requires understanding parental concerns. Begin with open-ended questions to identify underlying beliefs and information gaps.”

MCCQE1 Objectives – Preventive Medicine > Immunization:

“Candidates must demonstrate effective communication with vaccine-hesitant parents, beginning with eliciting their rationale before providing evidence-based recommendations.”

Jumping to education (B) or punitive measures (C, D) may close communication. The patient is an adult; speaking with her parents (E) violates her autonomy.

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Children with a first-degree relative who has premature coronary artery disease or hypercholesterolemia should undergo fasting lipid screening between ages 2–10. Since the child is 10, screening is indicated.

Toronto Notes 2023 – Pediatrics, “Preventive Care in Children”:

“Lipid screening is recommended for children ≥2 years old with a family history of early cardiovascular disease or hypercholesterolemia.”

MCCQE1 Objectives (Pediatrics > 78-1: Preventive Medicine):

“Candidates must screen children at high risk of cardiovascular disease appropriately, including lipid profile for familial hyperlipidemia.”

Diet and exercise counseling may follow screening, but testing is the first step. Reassurance alone (C) is inappropriate. Homocysteine (E) and HbA1c are not first-line tests in this setting.

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Physicians in Canada may charge patients for uninsured services (e.g., completion of forms, cosmetic procedures, some travel-related vaccines), but they may not charge extra for insured services or preferential access. Doing so violates the Canada Health Act, which mandates accessibility and universality of insured services.

Toronto Notes 2023 – ELOM, Health Care System:

“Physicians may charge for uninsured services but may not charge block fees for insured services, nor can they charge for expedited access to insured services.”

MCCQE1 Objectives – ELOM > Health Policy and System:

“Candidates must recognize practices that violate the principles of publicly funded health care, including charging for insured services or access premiums.”

Option A is not permitted under law. Options B, D, and E involve insured services (e.g., home visits, after-hours care) and cannot be billed directly to patients.

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The most important factor in determining the surveillance interval in Barrett esophagus is the presence and grade of dysplasia (e.g., none, low-grade, high-grade). High-grade dysplasia requires more frequent monitoring or intervention due to the risk of progression to esophageal adenocarcinoma.

Toronto Notes 2023 – Gastroenterology, Barrett Esophagus:

“Surveillance intervals depend on histologic findings. No dysplasia: q3–5 years; low-grade: q6–12 months; high-grade: consider endoscopic resection or ablation.”

MCCQE1 Objectives – Internal Medicine > Gastroenterology:

“Candidates must identify the risk of progression in Barrett esophagus and apply appropriate surveillance strategies based on dysplasia.”

Length of the segment (A) may influence risk but not surveillance frequency alone. Other options (B, C, E) are less determinative.

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Primary herpetic gingivostomatitis caused by HSV-1 is common in toddlers. It presents with high fever, irritability, drooling, refusal to eat, and painful oral ulcers on the lips, gums, and tongue. Cervical lymphadenopathy is common.

Toronto Notes 2023 – Pediatrics, “Infectious Conditions in Children”:

“Primary HSV-1 infection in children presents with high fever, cervical lymphadenopathy, and painful oral ulcers (gingivostomatitis).”

MCCQE1 Objectives (Pediatrics > 75-2: Infectious Diseases):

“Candidates must recognize viral exanthems and enanthems, including herpetic gingivostomatitis, based on clinical findings.”

Kawasaki (A) includes conjunctivitis, strawberry tongue, and extremity changes. Epiglottitis (B) presents with drooling but without oral ulcers. Mono (C) lacks the ulcerative pattern. Hand-foot-mouth (D) affects palms and soles, not inner lips and gums predominantly.

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This is a known patient with intellectual disability and behavioral concerns. The presentation of alcohol intoxication in a calm patient who inadvertently broke bottles warrants prompt, nonjudgmental clinical assessment before escalating. De-escalation and safety assessment come first.

Toronto Notes 2023 – Psychiatry, "Psychiatric Emergencies and Crisis Management":

“In agitated or intoxicated individuals with developmental disability, a calm approach and prompt physician assessment are essential to prevent escalation and assess for medical or psychiatric needs.”

MCCQE1 Objectives (Psychiatry > Crisis and Acute Presentations > 72-2):

“Candidates must assess potentially disruptive patients with dignity and caution before involving law enforcement or security. Physician engagement is often calming.”

Police intervention (A) is premature and may escalate matters. Ignoring (B) risks safety. Asking him to leave (C) without assessment is inappropriate. Social work (E) may help, but after medical triage.

This patient exhibits classic symptoms of a major depressive episode (MDE): anhedonia, low mood, social withdrawal, feelings of worthlessness, hypersomnia, and loss of appetite. These symptoms are persistent and pervasive beyond what is typical in grief.

Toronto Notes 2023 – Psychiatry, “Depressive Disorders” Section:

“MDE is characterized by ≥5 symptoms present nearly every day for ≥2 weeks including low mood, anhedonia, sleep/appetite disturbances, low energy, feelings of worthlessness, and suicidal ideation. It must cause significant impairment in functioning.”

MCCQE1 Objectives (Psychiatry > 79-1: Mood Disorders):

“Candidates must distinguish between grief, adjustment disorders, and major depression in patients with chronic illness and initiate appropriate management.”

Normal grief (A) may involve sadness and crying but does not involve pervasive hopelessness or worthlessness. Side effects of chemotherapy (C) and hepatic encephalopathy (E) have other specific physical signs. Brain metastasis (D) would more likely present with focal neurologic symptoms or cognitive impairment.

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Comprehensive and Detailed Explanation:

Cognitive behavioral therapy (CBT) is the most effective first-line treatment for somatic symptom disorder. It helps patients reframe dysfunctional thoughts and improve coping strategies for perceived physical symptoms.

Toronto Notes 2023 – Psychiatry, “Somatic Symptom and Related Disorders”:

“CBT is first-line for somatic symptom disorder. Antidepressants may be considered if comorbid depression or anxiety is present.”

MCCQE1 Objectives (Psychiatry > 71-2: Somatic Symptom Disorders):

“Candidates must manage somatic symptom disorder with appropriate psychosocial interventions.”

Citalopram (B) or amitriptyline (E) may be used adjunctively if mood symptoms are prominent. Risperidone (C) and ERP (D) are not indicated.

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Comprehensive and Detailed Explanation:

The ECG reveals:

Regular P waves that are not consistently followed by QRS complexes

A dissociation between the atrial (P wave) and ventricular (QRS complex) activity

A slow ventricular rate (~40 bpm) independent of atrial rate

These findings are characteristic of a third-degree (complete) atrioventricular (AV) block, where there is no conduction of atrial impulses to the ventricles. The atria and ventricles beatindependently, and the ventricular rate is maintained by an escape rhythm, often junctional or ventricular in origin.

This correlates with the patient’s symptoms (dizziness, hypotension) and bradycardia, suggesting inadequate cardiac output due to AV dissociation.

Toronto Notes 2023 – Cardiology:

“Third-degree AV block shows complete AV dissociation with independent atrial and ventricular activity. It typically presents with bradycardia and hypotension. Urgent pacing may be required.”

MCCQE1 Objectives (Cardiology > 34-2: Bradyarrhythmias and Conduction Disorders):

“Candidates must identify complete heart block and recognize its clinical urgency.”

Ruling out other options:

A. Sinus bradycardia would show regular P waves with 1:1 P-QRS conduction.

B. First-degree AV block has prolonged PR intervals (>200 ms) but all P waves are conducted.

D. Junctional escape rhythm may present with bradycardia, but P waves would be absent, inverted, or occur after QRS complexes.

E. Mobitz type I (Wenckebach) has progressively lengthening PR intervals before a dropped QRS.

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In a euthyroid patient with an asymptomatic goiter or thyroid enlargement, the next step is a thyroid ultrasound to evaluate nodule size, composition, and features suggestive of malignancy.

Toronto Notes 2023 – Endocrinology, Thyroid Nodules and Goiter:

“TSH should be obtained first. If normal and there is a palpable mass or enlargement, ultrasound is indicated to evaluate for nodules and guide further testing (e.g., FNA).”

MCCQE1 Objectives – Internal Medicine > Endocrinology:

“Candidates must use thyroid ultrasound as the initial imaging study in the evaluation of thyroid enlargement or palpable nodules.”

T3/T4 (A) are not needed with normal TSH. FNA (D) is done if nodules are identified. CT (C) is used for retrosternal goiters or compressive symptoms. Calcium (E) is irrelevant here.

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Respecting patient autonomy requires understanding their perspective before offering persuasion or incentives. The best next step is to explore the reason for non-compliance. This builds rapport and informs a shared decision-making process.

Toronto Notes 2023 – ELOM, Patient-Centered Communication:

“When a patient refuses recommended treatment, explore the reason behind the refusal before proceeding. Shared decision-making is crucial.”

MCCQE1 Objectives – ELOM > Communication and Consent:

“Candidates must demonstrate an ability to explore reasons for treatment refusal before counseling or modifying management.”

Options B and C may follow later. Options D and E can undermine appropriate pharmacologic care or violate ethics if not consented.

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The clinical picture is most consistent with acute pancreatitis (alcohol-related, epigastric pain radiating to back, vomiting, and ileus). CT abdomen with contrast is the best diagnostic tool if the diagnosis is uncertain or complications are suspected.

Toronto Notes 2023 – Gastroenterology, “Pancreatitis”:

“CT abdomen is indicated when diagnosis is unclear, symptoms are severe, or complications (e.g., necrosis, ileus) are suspected.”

MCCQE1 Objectives (Gastroenterology > 47-1: Acute Abdominal Pain):

“Candidates must investigate acute epigastric pain appropriately, especially in the context of alcohol use and systemic features.”

Ultrasound (B) is first-line for gallstones but not best here. Laparotomy (A) is not warranted without peritonitis or perforation. Endoscopy (D) is not indicated. Sengstaken-Blakemore (E) is for variceal bleeding, which is not suspected here.

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The patient describes classic symptoms of depersonalization (“my voice sounds strange to me”) and derealization (“others seem like figures in a dream”), which define depersonalization/derealization disorder. There is preserved reality testing and no psychosis.

Toronto Notes 2023 – Psychiatry, “Dissociative Disorders” Section:

“Depersonalization/derealization disorder involves persistent or recurrent experiences of detachment from oneself (depersonalization) or surroundings (derealization), with intact reality testing and no delusions or hallucinations.”

MCCQE1 Objectives (Psychiatry > 79-4: Dissociative Disorders):

“Candidates must identify depersonalization/derealization disorder as a dissociative disorder distinct from psychosis or mood disorders.”

Schizophrenia (A) would include hallucinations or disorganized thinking. Conversion disorder (B) presents with neurological symptoms inconsistent with known diseases. Persistent depressive disorder (D) involves chronic low mood. Delusional disorder (E) would involve fixed false beliefs, which are not present here.

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This infant has evidence of urinary outflow obstruction on ultrasound. The most common cause in male infants is posterior urethral valves. Poor urinary stream is a hallmark symptom of bladder outlet obstruction in neonates.

Toronto Notes 2023 – Pediatrics, “Pediatric Urology” Section:

“Posterior urethral valves should be suspected in male infants with recurrent UTIs, hydronephrosis, and a weak urinary stream. Diagnosis is confirmed by voiding cystourethrogram.”

MCCQE1 Objectives (Pediatrics > 78-4: Urinary Tract Abnormalities):

“Candidates must identify congenital causes of urinary obstruction. Poor stream and hydronephrosis are classic features of posterior urethral valves.”

Crying with urination (E) is nonspecific. Hematuria (B) and malodorous urine (D) are common with infections. Circumcision (A) is unrelated.

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Accurate dating is critical in pregnancies at high risk for preeclampsia and intrauterine growthrestriction. First-trimester ultrasound is used to establish gestational age, which guides monitoring and interventions.

Toronto Notes 2023 – Obstetrics, High-Risk Pregnancy:

“In women with a history of preeclampsia, early and accurate dating allows for appropriate fetal surveillance and timely delivery.”

MCCQE1 Objectives – Obstetrics > Prenatal Care:

“Candidates should recognize the importance of accurate pregnancy dating in high-risk pregnancies.”

Prophylactic labetalol (E) is not indicated in normotensive patients. Genetic testing (A, B) is not appropriate unless additional risk factors are present. Bed rest (D) is not evidence-based for preeclampsia prevention.

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Valproic acid is well known to cause thrombocytopenia, especially at higher serum concentrations or in patients over 60. Bruising with platelet count <100 × 10⁹/L is a classic manifestation.

Toronto Notes 2023 – Psychiatry, Mood Disorders & Pharmacology Section:

“Valproic acid is associated with hematologic side effects including thrombocytopenia. Platelet counts should be monitored regularly.”

MCCQE1 Objectives – Psychiatry > Pharmacotherapy:

“The candidate must recognize adverse effects of mood stabilizers including hematologic complications of valproic acid.”

Other listed medications (A–D) have no common or direct link with thrombocytopenia in this context.

Comprehensive and Detailed Explanation:

The most appropriate next step is to assess the patient’s capacity to consent to or refuse treatment. Patients with severe anorexia nervosa may lack decision-making capacity due todistorted thinking and perception, particularly if refusal of treatment is life-threatening. If she is found incapable, treatment can proceed in her best interests.

Toronto Notes 2023 – Psychiatry / Ethics:

“If a patient with anorexia nervosa refuses treatment but is medically unstable, assess capacity. If incapable, substitute decision-making may be initiated.”

MCCQE1 Objectives (ELOM > 90-4: Informed Consent and Capacity):

“Candidates must assess decision-making capacity when a patient refuses essential care, especially in life-threatening psychiatric or medical conditions.”

Psychiatric consult (B) may follow, but the immediate action is capacity assessment. D is premature without determining capacity. A and E are also premature or inappropriate.

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When couples face infertility-related decisions—particularly involving donor insemination—psychosocial counseling is essential. A mental health consultation helps explore emotional concerns, expectations, and readiness for non-biological parenting.

Toronto Notes 2023 – Gynecology, “Infertility and ART”:

“Psychological counseling is recommended for couples considering donor gametes to address emotional, ethical, and identity issues before proceeding.”

MCCQE1 Objectives (ELOM > Reproductive Ethics > 83-1):

“Candidates must understand the ethical and psychosocial considerations of assisted reproductive techniques and provide appropriate referrals.”

Suggesting adoption or switching care dismisses valid concerns (B, C). Ovulation induction (D) does not address azoospermia.

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Wernicke encephalopathy is a medical emergency caused by thiamine (vitamin B1) deficiency, most often seen in chronic alcohol use. The classic triad is:

Confusion

Oculomotor dysfunction (e.g., nystagmus, cranial nerve palsies)

Ataxia

Toronto Notes 2023 – Neurology and Psychiatry, “Wernicke Encephalopathy” Section:

“Wernicke encephalopathy is diagnosed clinically. Symptoms include ophthalmoplegia (e.g., CN VI palsy), horizontal nystagmus, ataxia, and confusion. Immediate parenteral thiamine is indicated before glucose administration.”

MCCQE1 Objectives (Neurology > 75-1: Neurologic Emergencies):

“Candidates must recognize Wernicke encephalopathy in at-risk individuals and initiate urgent thiamine replacement.”

Other choices like cerebellar degeneration (A) and hepatic encephalopathy (D) are more chronic and lack the characteristic eye findings. Subdural hematoma (B) and hemorrhage (E) may mimic confusion but are less likely with these neurologic signs and history.

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This is a classic presentation of acute acetaminophen (paracetamol) overdose. The most serious consequence, especially with delayed treatment, is fulminant hepatic failure.

Toronto Notes 2023 – Toxicology, Acetaminophen Toxicity:

“Acetaminophen overdose is the most common cause of acute liver failure. Delayed presentation leads to jaundice, coagulopathy, encephalopathy, and possible death.”

MCCQE1 Objectives – Internal Medicine > Toxicology:

“Candidates must identify acetaminophen overdose by clinical history and recognize fulminant hepatic failure as a primary complication.”

Cerebral edema (C) may occur secondarily, but fulminant hepatic failure is the most direct and expected outcome. Renal failure (B), arrhythmias (E), and seizures (A) are not typical with acetaminophen.

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A confounder is a variable associated with both the exposure and the outcome but not in the causal pathway. In this study, coffee drinking is associated with smoking (the actual risk factor for lung cancer), but not independently associated with lung cancer.

Toronto Notes 2023 – Epidemiology Chapter:

“A confounder is a third variable that distorts the observed association between an exposure and an outcome. It must be associated with both the exposure and the outcome, but not a result of the exposure.”

MCCQE1 Objectives (Population Health > 97-3: Study Design and Bias):

“Recognize and control for confounding in the interpretation of observational study data.”

Coffee is not a risk factor (B) since it’s not independently associated with lung cancer, and it's not selection bias (C), which involves how participants are enrolled in a study.

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The presentation is consistent with cervical spondylosis — a degenerative condition. In the absence of neurologic findings, further imaging beyond plain radiography is not warranted. Management includes conservative measures such as physiotherapy and analgesia.

Toronto Notes 2023 – Rheumatology, Cervical Spondylosis:

“Patients with typical cervical spondylosis and no red flags (e.g., neurologic deficits) do not require MRI. Treatment is conservative. Radiographs showing disc space narrowing and osteophytes confirm diagnosis.”

MCCQE1 Objectives – Internal Medicine > Musculoskeletal Disorders:

“Candidates must recognize typical degenerative spine disorders and avoid unnecessary investigations when clinical findings are straightforward.”

MRI (B) is useful if myelopathy or radiculopathy is suspected. CT (A), EMG (C), and LP (D) are not indicated here.

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The presentation is highly suspicious for acute aortic dissection — sudden chest/back pain and mediastinal widening on chest x-ray. The most definitive and widely available test is contrast-enhanced computed tomography (CT) of the chest.

Toronto Notes 2023 – Cardiology, Aortic Dissection:

“CT angiography of the chest is the gold standard for stable patients with suspected aortic dissection. Look for mediastinal widening on chest x-ray as a clue.”

MCCQE1 Objectives – Internal Medicine > Cardiovascular Disease:

“Candidates should recognize acute aortic dissection and select appropriate imaging, such as CT chest, for diagnosis in stable patients.”

Transthoracic echo (A) may miss dissections. ECG (C) helps rule out MI but not dissection. V/Q scan (D) and pulmonary angiography (E) are for suspected pulmonary embolism.

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Comprehensive and Detailed Explanation:

This patient has tardive dyskinesia, a late-onset, often irreversible movement disorder caused by chronic dopamine receptor blockade (e.g., haloperidol). It is especially common in older adults and may not resolve after stopping the drug.

Toronto Notes 2023 – Psychiatry, “Extrapyramidal Symptoms”:

“Tardive dyskinesia is often irreversible and typically occurs after prolonged antipsychotic use. Elderly patients are at greater risk.”

MCCQE1 Objectives (Psychiatry > 71-5: Side Effects of Psychotropics):

“Candidates must recognize tardive dyskinesia and understand that it can persist or worsen even after discontinuation of antipsychotics.”

Anticholinergics may worsen it (D). The condition does not reliably improve with age (C). It does not affect a majority of patients (A).

This patient has classic signs of cardiac tamponade (Beck's triad: hypotension, muffled heartsounds, elevated JVP, plus pulsus paradoxus). However, she also has advanced metastatic cancer, functional decline, and has stopped active treatment. In this context, a goals-of-care discussion is the most appropriate next step to determine her wishes regarding interventions like pericardiocentesis.

Toronto Notes 2023 – Palliative Care:

“End-of-life care should prioritize quality of life and patient preferences. In patients with terminal illness and life-threatening conditions (e.g., tamponade), initiate a conversation about goals before aggressive intervention.”

MCCQE1 Objectives – Internal Medicine > Palliative and End-of-Life Care:

“Candidates must assess prognosis, patient values, and initiate appropriate end-of-life discussions before invasive treatment.”

Although pericardiocentesis (A) may relieve symptoms, it should follow consent based on the patient’s goals. ICU (E), fluids (B), or transfusion (D) are not appropriate without this discussion.