MCCQE Exam Dumps - Medical Council of Canada MCCQE Part 1 Questions and Answers

This presentation is most consistent with amyotrophic lateral sclerosis (ALS), characterized by progressive degeneration of both upper motor neurons (UMN) and lower motor neurons (LMN). The patient has LMN signs in the upper limbs—muscle atrophy of the shoulder girdle and visible fasciculations—alongside UMN signs—hyperreflexia, ankle clonus, and a Babinski reflex. The combination of UMN and LMN findings in multiple body regions with a gradual, progressive course over months strongly supports ALS. Multiple sclerosis typically produces disseminated neurologic deficits separated in time and space and does not usually cause prominent fasciculations or progressive LMN wasting. Cerebellar degeneration causes ataxia, dysmetria, and gait instability rather than mixed UMN/LMN signs. A pontine astrocytoma would more often cause cranial nerve deficits and brainstem signs and is less likely to present as a diffuse, progressive mixed motor neuron syndrome in an older adult. Parkinson disease causes bradykinesia, rigidity, and resting tremor, not Babinski or fasciculations. MCCQE objectives emphasize recognizing mixed UMN/LMN patterns and identifying ALS as a key progressive motor neuron disorder.

This presentation has “red flags” for raised intracranial pressure: headaches that are progressive, worse in the morning, and worsened by coughing/valsalva. In MCCQE objectives, these features require urgent evaluation for secondary causes (e.g., intracranial mass, hemorrhage, obstructive hydrocephalus) rather than empiric treatment for primary headache. His chronic cough and heavy smoking increase concern for an underlying malignancy with possible brain metastasis or paraneoplastic processes, further strengthening the indication for neuroimaging. Therefore, the best next step is CT head (often the fastest initial test to identify mass effect, hemorrhage, or hydrocephalus; MRI may follow depending on findings).

Treating presumed migraine with a triptan is inappropriate when secondary headache is possible and could also pose vascular risk. His blood pressure is elevated but not in a hypertensive emergency and does not explain these classic intracranial pressure features; serial BP monitoring or starting antihypertensives should not delay imaging. Temporal arteritis is less likely without temporal tenderness, jaw claudication, visual symptoms, or systemic inflammatory clues.

These are recurrent, brief (10–15 minute), fully resolving focal neurologic deficits, which fits transient ischemic attacks (TIAs) rather than completed stroke. The combination of right-sided arm and leg weakness and difficulty speaking localizes to the left cerebral hemisphere (dominant hemisphere for language in most patients). The additional symptom of transient blurring of vision in the left eye is characteristic of amaurosis fugax, caused by retinal ischemia from emboli or hypoperfusion in the ipsilateral internal carotid circulation. Together, this pattern strongly suggests left internal carotid artery occlusive disease (e.g., high-grade stenosis with artery-to-artery embolization).

Left MCA thrombosis would typically produce persistent deficits rather than multiple short, self-resolving episodes. Intracerebral hemorrhage usually presents with sudden severe symptoms that do not resolve quickly and often includes headache or reduced consciousness. Epilepsy would more likely cause positive symptoms (jerking, automatisms) and postictal confusion. Vertebrobasilar disease causes posterior circulation symptoms (vertigo, diplopia, ataxia), not unilateral monocular vision loss plus contralateral weakness.

Comprehensive and Detailed Explanation:

Infertility is defined as the inability to conceive after 12 months of regular, unprotected intercourse in women under 35 years. Since she has been trying for only 5 months, reassurance is appropriate.

Toronto Notes 2023 – Gynecology:

“Investigations for infertility in women under 35 should begin after 12 months of attempting to conceive, unless other risk factors are present.”

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

“Candidates must apply appropriate timing and indications for infertility investigations based on patient age and history.”

Earlier testing is not warranted here. Options A–D are part of the infertility work-up but not before 12 months.

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This patient had a single spontaneous abortion and is planning another pregnancy. MCCQE objectives emphasize modifiable risk factor reduction and evidence-based preconception counseling. Smoking is a well-established risk factor for miscarriage, placental complications, fetal growth restriction, and preterm birth. Therefore, smoking cessation is the most effective intervention among the options listed to improve the likelihood of a healthy term pregnancy.

A 2-cm subserosal fibroid does not distort the uterine cavity and is unlikely to contribute to miscarriage; surgical removal is not indicated. There is no evidence that abstaining from intercourse in the first trimester prevents miscarriage. After a single early pregnancy loss, there is no need to delay conception for 6 months; couples may attempt pregnancy once emotionally and physically ready.

While folic acid supplementation is recommended preconceptionally, the standard dose for low-risk women is 0.4–1 mg daily, not 5 mg (which is reserved for high-risk patients). Thus, smoking cessation is the most important advice.

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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The patient is obese (BMI 35), has type 2 diabetes, and shows a hepatocellular pattern of transaminitis (elevated ALT > AST). These are typical features of nonalcoholic steatohepatitis (NASH), the inflammatory subtype of nonalcoholic fatty liver disease (NAFLD).

Toronto Notes 2023 – Gastroenterology, NAFLD and NASH:

“NASH should be suspected in patients with metabolic syndrome, obesity, and type 2 diabetes, especially with elevated transaminases and normal bilirubin or INR.”

MCCQE1 Objectives – Internal Medicine > Hepatology:

“Candidates should recognize the clinical profile of NAFLD/NASH, particularly in asymptomatic patients with metabolic risk factors and isolated liver enzyme elevations.”

Acute hepatitis B (A) typically has higher ALT and symptoms. Pancreatic carcinoma (B) affects biliary enzymes or bilirubin. Metformin (D) does not elevate liver enzymes. HCC (E) would often present with systemic or localized symptoms and abnormal imaging.

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The presence of multiple cutaneous lesions along with numerous longstanding subcutaneous tumors is most consistent with neurofibromatosis type 1 (NF1) . MCCQE objectives emphasize recognizing classic dermatologic findings of NF1, which include multiple neurofibromas (soft, skin-colored subcutaneous nodules) and characteristic pigmented lesions such as café-au-lait macules and axillary or inguinal freckling. These lesions typically develop during childhood or adolescence and increase in number over time.

Sarcoidosis can cause skin lesions but is not associated with multiple benign peripheral nerve sheath tumors. Dermatofibromas are usually solitary, firm nodules rather than numerous soft tumors. Vitiligo presents as depigmented macules without subcutaneous masses. Lipomatosis involves multiple lipomas but lacks the associated pigmentary skin findings seen in NF1.

NF1 is an autosomal dominant condition caused by mutation of the NF1 gene. Diagnosis is clinical based on established criteria. Recognition is important because patients require surveillance for complications such as optic gliomas, learning disabilities, skeletal abnormalities, and malignant peripheral nerve sheath tumors.

The clinical presentation of mild prodromal symptoms followed by oral lesions in a school-aged child is most consistent with a viral stomatitis such as primary herpes simplex virus (HSV-1) infection. HSV-1 is highly contagious and is transmitted primarily through direct contact with infected oral secretions. According to MCCQE objectives on pediatric infectious diseases, prevention of transmission relies on appropriate infection control measures, particularly avoidance of sharing utensils, cups, toothbrushes, and minimizing direct contact such as kissing during the active lesion phase. Antibiotics are not indicated because this is a viral infection. Routine antiviral prophylaxis for healthy siblings is not recommended. Varicella vaccination is unrelated to HSV infection and would not prevent spread. The condition is contagious, especially when lesions are present and viral shedding occurs. Therefore, counseling families regarding strict hand hygiene and avoidance of direct contact with oral secretions is the most appropriate preventive strategy.

Comprehensive and Detailed Explanation:

In X-linked recessive disorders such as hemophilia A, carrier mothers (usually asymptomatic) have a 50% chance of passing the affected X chromosome to each son, who would then express the disease. Each daughter has a 50% chance of being a carrier but is generally not affected.

Toronto Notes 2023 – Genetics:

“X-linked recessive inheritance: Carrier mother has a 50% chance of having an affected son and a 50% chance of having a carrier daughter.”

MCCQE1 Objectives (Genetics > 61-1: Inheritance Patterns):

“Candidates must apply principles of X-linked inheritance to assess risk in offspring.”

If the mother is a known carrier (as inferred from having an affected son), the chance of a second affected boy is 50%.

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