🇨🇦 MCCQE1,2 | #Case_43 | #answer
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✅ A

🔎 Explanation

Clinical trials support the treatment of systolic hypertension in the older person with a systolic blood pressure of at least 150 mm Hg. Systolic hypertension is defined as systolic blood pressure of at least 140 mm Hg and a diastolic blood pressure of less than 90 mm Hg. The studies most strongly support the use of thiazide diuretics and long-acting calcium channel blockers as first-line therapy.

⚠ Alpha-blockers are not recommended.

⚠ ACE inhibitors, beta-blockers, and angiotensin receptor blockers are used when certain compelling indications are present, e.g. in a patient with diabetes or who has had a myocardial infarction.

🇨🇦 MCCQE1,2 | #Case_44
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A 40-year-old man presents to the emergency department with acute onset pain and inability to open his right eye.On examination you find, on his right eye, there is complete eyelid ptosis, lateral deviation of the eye, and a dilated pupil, which does not react to light. Which investigation is most useful for confirming or excluding a diagnosis that would require an urgent intervention in this patient?

a) Magnetic Resonance Imaging (MRI) of head
b) Magnetic Resonance Angiogram (MRA) of head
c) Serum glucose level
d) Lumbar puncture
e) Computed Tomography (CT) scan of the head

🇨🇦 MCCQE1,2 | #Case_44 | #answer
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✅ B

🔎 Explanation

Third cranial nerve(oculomotor nerve) supplies all extraocular muscles (levator palpebrae, superior rectus, medial rectus, inferior rectus, and the inferior oblique) except the lateral rectus (supplied by the sixth cranial nerve) and the superior oblique (supplied by the fourth cranial nerve). Third cranial nerve also gives parasympathetic fibers to iris sphincter (constrictor) and the ciliary muscle of the eye. In a cross section of the nerve, the parasympathetic fibers are found closer to the surface of the nerve; therefore are almost always affected when a compressive lesion (e.g. berry aneurysm of the circle of Willis) is the cause for the third nerve palsy. The patient would have a dilated pupil in addition to eyelid ptosis and lateral deviation of the eye ball. In contrast, when third nerve palsy is the result of microvascular disease (e.g. diabetes, hypertension) these parasympathetic fibers may be spared and the patient may have eye lid ptosis and lateral
deviation of the eye without pupillary dilation. Patient with a third nerve palsy may not complain of double vision
(diplopia) if the eyelid ptosis is severe enough to cover the visual axis of the affected eye.Any patient presenting with eyelid ptosis, lateral deviation of the eye, and a dilated pupil should be investigated to exclude a compressive lesion. If the third cranial nerve palsy is caused by a Berry aneurysm of the circle of Willis, surgical
intervention may not only relieve patient’s symptoms but could also be lifesaving. Among the choices given, MRA (a non-invasive test) is the investigation of choice to confirm a diagnosis of Berry aneurysm (choice B).

⚠ Serum glucose level (choice C) is useful, to confirm or exclude diabetes (i.e. microvascular disease), if the patient had eyelid ptosis and lateral deviation of the eye without pupillary involvement.

⚠ MRI of head (choice A) and CT scan of head (choice E) may not be sensitive enough to detect a small Berry aneurysm unless an intravenous contrast agent is used.

⚠ A lumbar puncture (choice D) should not be performed prior to neuroimaging in a patient suspected of having an intracranial lesion as it may lead to either trans-tentorial or uncal herniation and acute neurological deterioration.

✅Key point:

In a patient presenting with eyelid ptosis, lateral deviation of eye (with or without double vision) and a dilated pupil the possibility of a Berry aneurysm of the circle of Willis impinging on the third cranial nerve must be considered. MRA of head is the investigation of choice under such circumstances.

🇨🇦 MCCQE1,2 | #Case_45
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An 18-year-old female is brought to your department by her worried parents, because of her missed menstrual periods for the last 4 months and a very low weight. On questioning, the patient says that she has no appetite, denies any vomiting, and says that she is more interested in exercise to stay fit because she thinks she is “still super fat.” She denies laxative use. She reports having a boyfriend but she is not sexually active.Physical examination reveals a BMI of 15 kg/m2, dry skin, and cold hands. Which of the following is most likely to be present in this patient?

a) Bradycardia
b) Elevated serum FSH
c) Elevated serum beta-hCG
d) Hypoalbuminemia
e) Shortened QT interval on ECG

🇨🇦 MCCQE1,2 | #Case_45 | #answer
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✅ A

🔎 Explanation

This patient’s diagnosis is most likely anorexia nervosa. The DSM-V criteria for diagnosing anorexia nervosa include refusal to maintain appropriate body weight, intense fear of becoming fat, undue influence of body weight or shape on self-evaluation, and amenorrhea.Anorexia nervosa can have serious implications if its duration and severity are significant. Medical complications resulting from semi-starvation and overexercising affect virtually every organ system. Common signs and symptoms include loss of subcutaneous fat tissue, orthostatic hypotension, bradycardia (choice A), impaired menstrual function, hair loss, and hypothermia.

⚠ Elevated serum FSH (choice B) is incorrect. Amenorrhea in anorexia nervosa is caused by the hypothalamic-pituitary axis failure and is characterized by low levels of FSH.

⚠ Elevated serum beta hCG (choice C) would be seen in amenorrhea due to pregnancy or trophoblastic neoplasias.

⚠ Hypoalbuminemia (choice D) is incorrect. Albumin and protein levels are usually normal.

⚠ Shortened QT interval on ECG (choice E) is incorrect. Anorexia nervosa is associated with hypocalcemia and prolonged QT interval on ECG.

✅Key point:

The diagnosis of anorexia nervosa includes refusal to maintain appropriate body weight, intense fear of becoming fat, undue influence of body weight or shape on self-evaluation, and amenorrhea. Anorexia nervosa is associated with bradycardia and orthostatic hypotension.

🇨🇦 MCCQE1,2 | #Case_46
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A 45-year-old white male undergoes a health screening at his church. He has a carotid Doppler study, abdominal
ultrasonography, heel densitometry, and a multiphasic blood panel. He receives a report indicating that all of the studies
are normal, but a 0.7-cm thyroid nodule was noted. The TSH level is normal. He schedules a visit with you and brings you the report. A neck examination and ENT examination are normal, and you do not detect a nodule. His past medical history and family history are unremarkable. You recommend:

a) A radionuclide thyroid scan
b) T3, T4, and calcitonin levels
c) Repeat ultrasonography in 6-12 months
d) A fine-needle biopsy
e) Hemithyroidectomy

🇨🇦 MCCQE1,2 | #Case_46 | #answer
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✅ C

🔎 Explanation

This is a classic incidentaloma. Nodules are detected in up to 50% of thyroid sonograms and carry a low risk of malignancy (< 5%). If the TSH level is normal, nuclear scanning and further thyroid studies are not necessary. Nodules smaller than 1 cm are difficult to biopsy and thyroid surgery is not indicated for what is almost certainly benign disease. It is reasonable to follow small nodules with clinical examinations and periodic sonograms.

Note:

🔹all patients with thyroid nodules require evaluation of serum TSH and ultrasound
🔹any nodule > 5 mm with suspicious sonographic features (particularly microcalcifications) should undergo FNA
🔹anynodule > 1cm should undergo FNA
🔹when performing repeat FNA on initially non-diagnostic nodules, U/S-guided FNA should be employed
🔹nuclear scanning has minimal value in the investigation ofthe thyroid nodule

🇨🇦 MCCQE1,2 | #Case_47
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A 25-year-old clinically healthy black female is involved in a minor auto accident. Chest radiographs obtained after the wreck reveal bilateral hilar lymphadenopathy. She has no history of environmental exposures and has no symptoms. A physical examination is completely normal. Your initial workup includes a normal comprehensive metabolic panel, CBC, and urinalysis; a negative tuberculin skin test; a normal EKG; and normal pulmonary function tests. A transbronchial lung biopsy specimen reveals a noncaseating epithelioid granuloma.Which one of the following would be the most appropriate treatment at this time?

a) Long-term high-dose systemic corticosteroids
b) Pulsed doses of systemic corticosteroids
c) Inhaled corticosteroids
d) Oral methotrexate weekly
e) Observation only

🇨🇦 MCCQE1,2 | #Case_47 | #answer
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✅ E

🔎 Explanation

Sarcoidosis is a disease of unknown cause characterized by the presence of noncaseating epithelioid granulomas; it involves many different organ systems. The lungs are commonly involved, with bilateral hilar lymphadenopathy being
commonly present and pulmonary infiltrates and fibrosis somewhat typical. Other frequent areas of involvement include the skin, central nervous system, eyes, liver, heart, salivary glands, kidneys, muscles, and bones. When the disease is limited to asymptomatic hilar adenopathy, it is termed stage I and no treatment has been shown to be beneficial. The most appropriate management of stage I patients is routine follow-up.

🇨🇦 MCCQE1,2 | #Case_48
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A 16-year-old white female is brought to your office because she has been “passing out”. She tells you that on several occasions while playing in the high-school band at the end of the half-time show she has “blacked out”. She describes feeling lightheaded with spots before her eyes and tunnel vision just prior to falling. Friends in the band have told her that she appears to be pale and sweaty when these episodes occur. No seizure activity has ever been observed. In each instance she regains consciousness almost immediately; there is no postictal state. She has been seen in the emergency department for this on two occasions with normal vital
signs, physical findings, and neurologic findings. A CBC, a metabolic profile, and an EKG are also normal. Which one of the following tests is most likely to yield the correct diagnosis?

a) A sleep-deprived EEG
b) 24-hour Holter monitoring
c) A pulmonary/cardiac stress test
d) An echocardiogram
e) Tilt table testing

🇨🇦 MCCQE1,2 | #Case_48 | #answer
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✅ E

🔎 Explanation

Reflex syncope is a strong diagnostic consideration for episodes of syncope associated with a characteristic precipitating factor. The major categories of syncope include carotid sinus hypersensitivity, and neurally mediated and situational syncopes. The most common and benign forms of syncope are neurally mediated or vasovagal types with sudden hypotension, frequently accompanied by bradycardia. Other terms for this include neurocardiogenic, vasomotor, neurovascular, or vasodepressive syncope. Most patients are young and otherwise healthy. The mechanism of the syncope seems to be a period of high sympathetic tone (often induced by pain or fear), followed by sudden sympathetic withdrawal, which then triggers a paradoxical vasodilation and hypotension. Attacks occur with upright posture, often accompanied by a feeling of warmth or cold sweating, lightheadedness, yawning, or dimming of vision. If the patient does not lie down quickly he or she will fall, with the horizontal position allowing a rapid restoration of central perfusion. Recovery is rapid, with no focal neurologic sense of confusion or headache. The event can be duplicated with tilt testing, demonstrating hypotension and bradycardia.

🇨🇦 MCCQE1,2 | #Case_49
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A 35-year-old male who works as an EMT has recently developed deep, severe, continuous headaches behind his left eye. The headaches occur daily around 10:00 a.m. and last 1-2 hours. He notes that the headaches bother him less when he remains active. When the headaches occur he also has tearing from the left eye and a nasal discharge from the left naris.He has found that using oxygen gives him relief. A physical examination reveals no significant findings.
Which one of the following would be most appropriate at this time?

a) MRI
b) Carbamazepine (Tegretol)
c) Neurologic consultation
d) Avoiding triptan medications such as sumatriptan (Imitrex)
e) Daily therapy with verapamil (Isoptin)

🇨🇦 MCCQE1,2 | #Case_49 | #answer
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✅ E

🔎 Explanation

Cluster headaches are repetitive headaches that occur for weeks or months at a time. They are more common in men between the ages of 30 and 50. The headaches begin without warning and reach a crescendo within minutes. Most times the headaches are located behind the eye or at the temple, and are associated with ipsilateral lacrimation, redness of the eye, nasal stuffiness,sweating, pallor, and Horner’s syndrome. Patients note that they are sensitive to alcohol. They often prefer to remain active rather than rest in a dark, quiet room as someone with a migraine would likely do. A typical attack will last from 30 minutes to 3 hours. It is common for the pain to recur each day at the same time. These attacks occur 1-3 times a day over a 4- to 8-week period. The patient will often remain pain-free for 6 months to a year.A cluster headache can be distinguished from a migraine, a tension-type headache, and a brain tumor by its presentation. Headaches associated with a brain tumor are often accompanied by nausea, vomiting, and worsening of the pain (which is usually bifrontal) with change in body position. There are usually positive findings on neurologic examination, as well as a change from the previous headache pattern. Migraines are more common in women and may be associated with an aura. They are throbbing in nature and accompanied by nausea, photophobia, and phonophobia. These patients are usually much more comfortable in the dark. Both cluster and migraine headaches will respond to abortive therapy with triptan medications.Prophylaxis for migraine is normally begun if there are four or more attacks within a month. In contrast, once the diagnosis of cluster headache is made, it is important to initiate both abortive and prophylactic therapy right away. Abortive therapy can be with 100% oxygen, triptans, octreotide, or dihydroergotamine. A number of prophylactic medications are available, including verapamil, lithium, prednisone (short-term use only), ergotamine, cyproheptadine, and indomethacin

🇨🇦 MCCQE1,2 | #Case_50
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A 67-year-old smoker, with a 40 pack year history of smoking cigarettes, comes to your office for an annual check up. He is known to have uncontrolled hypertension, with a BP today of 159/89 mmHg. Today he tells you that he is becoming short of breath, more so than usual. He also can manage about 2 blocks before he needs to sit at a bench, before he can resume. He tells you that his calf muscles begin to ache at the end of the two blocks and the pain is relieved after resting.You take an ankle-brachial pressure index (ABPI) measurement.What do you expect his ABPI value to be between?

a) > 1.5
b) 1
c) 1.0-0.7
d) 0.7-0.4
e) < 0.35

🇨🇦 MCCQE1,2 | #Case_50 | #answer
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✅ D

🔎 Explanation

This individual is experiencing claudicating pain, which is pain that begins upon exertion and ends with rest. Claudication is defined as reproducible ischemic muscle pain, which occurs during physical activity and is relieved after a short rest. Pain develops because of inadequate blood flow. A normal ABPI is between 0.9 and 1.2. You should expect the ABPI in someone with claudicating pain to lie between 0.7-0.4. When the ABPI is below 0.4, rest pain is a key sign to be aware of, and would indicate urgent vascular surgery to alleviate the ischemia.

🇨🇦 MCCQE1,2 | #Case_51
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A 44-year-old man presented to his family physician for evaluation of coronary artery disease (CAD) risk after his 47 years old brother sustained myocardial infarction a week ago. He has been a smoker for 20 years now, with smoking history of 20-pack year. Apart from his blood pressure of 145/87 mmHg, vital signs are otherwise stable. Lipid profile is as follows:
LDL: 3.5 mmol/L
Total cholesterol: 5.0 mmol/L
HDL: 0.8 mmol/L
His 10 years Framingham Risk Score is 13%.What is the best management option for this patient?

a) Reassess for risk of CAD in three years before considering treatment
b) Reassess for risk of CAD in one year before considering treatment
c) Initiate conservative treatment for 4 to 6 months with smoking cessation, diet and exercise before considering medical treatment
d) Initiate medical treatment with HMG-CoA reductase inhibitors immediately
e) Perform exercise stress testing before considering treatmen

🇨🇦 MCCQE 1,2 | #Case_51 | #answer
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✅ D

🔎 Explanation

Whether or not to initiate treatment and type of treatment of dyslipidemia is based on coronary artery disease (CAD) risk. Those in the high risk group should receive medical treatment with HMG-CoA reductase immediately. Our patient has family history of premature coronary artery disease (CAD) in first degree relative and this is known to double the risk of CAD. Thus, the 10 years risk of CAD in our patient is 26% (13 x 2) and this puts him in the high risk group. That's why the best management option is to initiate medical treatment with HMG-CoA reductase inhibitors (choice D).

⚠ Reassessment for risk of coronary artery disease in 3 years before considering treatment (choice A) is not the best management option. This patient has a high risk of CAD and treatment should start immediately. However, risk assessment should be performed every three years for this patient or any patient for whom risk assessment is indicated.

⚠ Reassess for risk of CAD in one year before considering treatment (choice B) is not the best management option. This patient has a high risk of CAD and treatment should start immediately. Also, if risk assessment were indicated it would be done every three years.

⚠ Initiate conservative treatment for 4 to 6 months with smoking cessation, diet, and exercise before considering medical treatment (choice C) is not the best management option. This patient has a high risk of CAD and treatment should start immediately.

⚠ Performing exercise stress testing (choice E) is not the best management option. Dyslipidemia is not an indication for exercise stress testing. This type of testing is indicated in patients with intermediate probability (10 to 90%) of having CAD based on age, gender, and presence of symptoms. Asymptomatic men and women have < 10% probability of having CAD and stress test is not indicated.

✅Key point:
After calculating the 10-year-risk score, consider risk modifiers like family history of premature CAD to decide on treatment of dyslipidemias. For patients in the high risk category medical treatment with HMG-CoA reductase inhibitors should be initiated immediately

🇨🇦 MCCQE1,2 | #Case_52
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A 59-year-old female with a history of hypertension, posttraumatic stress disorder, and sarcoidosis, reports a 3-month history of hair loss in the right temple area. She has been using an over-the-counter corticosteroid cream without response. Her other medications include ramipril (Altace), hydrochlorothiazide, clonazepam (Klonopin), and bupropion (Wellbutrin). She reports increased stress from caring for her chronically ill husband who has been hospitalized recently. Examination of the skin and scalp is normal except for a 3cm x 4cm irregularly shaped area of alopecia with a slightly red, raised anterior edge located in the right temporal scalp. The affected skin is shiny, with no scaling; no hairs or broken hairs are present.
The most likely cause of this patient’s hair loss is:

a) Drug-induced alopecia
b) Androgenic alopecia
c) Stress-induced alopecia areata
d) Sarcoidosis
e) Trichotillomania

🇨🇦 MCCQE1,2 | #Case_52 | #answer
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✅ D

🔎 Explanation

The condition of the skin in the affected area helps to differentiate the cause of hair loss. In this case, the abnormal skin suggests a scarring type of alopecia, which may be caused by infection (e.g. syphilis, tuberculosis, acquired immunodeficiency syndrome, herpes zoster), autoimmune disease (discoid lupus erythematosus), sarcoidosis, scalp trauma (e.g., injuries, burns), and radiation therapy.

⚠ The skin is normal in androgenic alopecia, alopecia areata, and drug-induced alopecia.

⚠ Trichotillomania, a compulsive plucking of one’s hair, may occur in the scalp. This can be differentiated from other forms of scarring alopecia by an examination of the scalp showing decreased hair density, as well as broken hairs of various lengths, rather than complete baldness in the affected area.

✏As the patient has known sarcoidosis, this is the most likely cause of her scarring alopecia.

🇨🇦 MCCQE1,2 | #Case_53
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A 46-year-old woman has had rheumatoid arthritis for 8 years. Her hands now show moderate ulnar deviation of the fingers and she says her wrists and knees also hurt. She says, "I had several drop attacks during the past 3 months." She characterizes these attacks as episodes of weakness and loss of feeling in her legs for several minutes. During one of these episodes, she became incontinent. On physical examination she has facial plethora and swollen and painful metacarpophalangeal and knee joints, bilaterally. The rest of the examination is normal.
Which of the following is the most likely cause of her "drop attacks?"

a) Adrenal insufficiency
b) Anxiety
c) Atlanto-occipital instability
d) Cardiac arrhythmia
e) Cerebral ischemia

🇨🇦 MCCQE1,2 | #Case_53 | #answer
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✅ C

🔎 Explanation

Given this patient's long history of rheumatoid arthritis her drop attacks are most likely caused by atlanto-occipital instability (choice C).The cervical spine is commonly affected by rheumatoid arthritis.The anatomic abnormalities occur as a consequence of the destruction of synovial joints, ligaments, and bone. Abnormalities of the rheumatoid cervical spine generally can be grouped into 3 categories that may be seen in isolation or combined involvement, of which atlantoaxial instability or atlanto-occipital instability is the most common abnormality.Superior migration of the odontoid
is the next most common abnormality, it is also referred to as cranial settling or pseudobasilar invagination.The third and least common deformity is subaxial subluxation.When rheumatoid arthritis affects the cervical spine, compression of the C2 sensory fibers supplying the nucleus of the spinal trigeminal tract can cause facial pain. Compression of the C2 sensory fibers supplying the greater auricular nerve may result in ear pain. Occipital neuralgia results from compression of the C2 sensory fibers supplying the greater occipital nerve. Drop attack in these patients can be either a manifestation of myelopathic symptoms or vertebrobasilar insufficiency or a combination of both.Patients may experience weakness, decreased endurance, gait difficulty, paresthesias of the hands,loss of fine dexterity, and eventually incontinenece.They may also complain of vertigo, loss of equilibrium, visual disturbances, tinnitus, and dysphagia.

⚠ Adrenal insufficiency (choice A) may cause syncope due to hypotension, it also causes muscle weakness and may even cause muscle and joint pains. Since this patient has facial plethora on physical examination and this could occur in a rheumartoid arthritis patient on long-term treatement with corticosteroids, it could be argued that an abrupt discontinuation of corticosteroid treatment could result in adrenal insufficiency. However, some of the symptoms she describes such as incontincence and numbness, and the fact that these symptoms have occured over the last 3 months (and not a sudden adrenal crisis caused by discontinuation of corticosteroid therapy), make this diagnosis less favorable than atlanto-occipital instability.

⚠ Anxiety (choice B) is a less common cause of urinary incontinence than the reverse.Urinary incontinence causes anxiety in many patients. When considering this patient's overall history, complaints of weakness and numbness, her symptoms are most likely associated with neurological dysfunction.

⚠Cardiac arrhythmia (choice D) may cause syncope accompanied by incontinence in minority of patients; however, in this patient, findings on physical examination and the overall history, should guide us to consider that causes of drop attacks are related to her past medical history , and therefore most likely linked to atlanto-axial instability, a well known complication of rheumatoid arthritis of cervical spine.

⚠ Cerebral ischemia (choice E) is most likely to be associated with atherosclerosis history.While some of the symptoms this patient describes could occur in cerebral ischemia, the history of these attacks for the last 3 months, her rheumatoid arthritis history, findings on physical examination, and absence of cardiovascular diseases in her history,should steer us towards a diagnosis of atlanto-occipital instability caused by rheumatoid arthritis.