Case-based MCQ

🇨🇦 MCCQE1,2 | #Case_108 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 70-year-old man presents to the ED with a severe shortness of breath and diaphoresis. His past medical history is significant for Diabetes and two previous MIs. He is taking metformin, pioglitazone, aspirin, losartan and rosuvastatin. His vitals are significant for a pulse rate of 110/min and a RR of 30/min. Physical exam shows JVD, lower limb pitting edema and bilateral basilar lung crackles. Which of the following medications is the most appropriate at this time? a) Beta-blockers b) Digoxin c) Lidocaine d) Mannitol e) Morphine

🇨🇦 MCCQE1,2 | #Case_107 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ C 🔎 Explanation This patient has athrombosed external hemorrhoid that requires immediate incision and evacuation of the clot to provide symptomatic relief.‌ Pressure by compression is usually all that is needed to control the bleeding. The typical presentation of a thrombosed external hemorrhoid is an acute onset of very severe perianal pain, particularly when walking and sitting. You know that it is an external hemorrhoid because it is below the dentate line.Acutely thrombosed external hemorrhoids may be safely excised in the emergency department in patients who present within 48-72 hours of symptom onset. In patients presenting after 72 hours from the start of symptoms, conservative medical therapy is preferable

🇨🇦 MCCQE1,2 | #Case_107 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A female patient presents with an acute onset of severe constant anal pain that has started about 2 days ago. She states that It gets worse during defecation, walking, and sitting. Physical examination and anoscopy show a tender, blue swelling below the dentate line. What is the most appropriate initial management? a) Hot bandages b) Sitz baths c) Immediate incision d) Systemic Antibiotics e) Topical Antibiotics

🇨🇦 MCCQE1,2 | #Case_107 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ C 🔎 Explanation This patient is complaining of nights sweats few hours after taking NPH and insulin aspart mix and his morning fasting glucose levels are 12.2 mmol/L (220 mg/d). Morning hyperglycemia in diabetic patients may be caused by the dawn phenomenon or the Somogyi’s effect, or simply poor glycemic control.The dawn phenomenon is associated with physiological (or pathological) decreased insulin secretion in the early morning hours, accompanied by increase of counterregulatory hormones, particularly the growth hormone. It can occur in patients with type 1 diabetes mellitus and type 2 diabetes mellitus. On the other hand, the Somogyi’s effect seems to be most associated with type 1 diabetes and its incidence is increased in young people who take NPH insulin. Hyperglycemia is usually preceded by hypoglycemia few hours earlier due to the effects of insulin treatment and this could be symptomatic or asymptomatic. This patient’s night time excessive sweating is most likely caused by hypoglycemia. It has been observed that in these patients the symptoms are not linked to the level of serum glucose itself as much as to the abrupt drop of it. A patient whose serum glucose dramatically falls from 5.6 mmol/l (100 mg/dl) to 3.3 mmol/l (60 mg/dl) in an hour is more likely to be symptomatic than a patient whose serum glucose level gradually decreases from 5.6 mmol/l (100 mg/dl) to 3.3 mmol (45 mg/dl) over 24 hours. For patients on NPH insulin treatment, hypoglycemic events can be connected with the evident peak of its concentration, taking place 4-5 hours after evening injections. The best recommendation to manage Somgyi's effect is to replace NPH insulin with a peakless long-acting analogue such as glargine or detemir (choice C). ⚠ Nocturnal hormonal measurements (choice A) have shown that patients with morning hyperglycemia have increased counterregulatory hormones, with growth hormone and glucagon being the most significant and consistent. This patient's condition is rather obvious and it's more appropriate to change from NPH insulin to long acting insulin than perform more diagnostic studies. ⚠ Reduce the evening dose of insulin by half (choice B) is incorrect. In patients treated with NPH insulin who present with hypoglycemia and Somogyi’s effect, the best treatment is switching to peakless long-acting insulin such as glargine or detemir; however, if, for some reason, NPH insulin must be used, an alternative is to subtract 2 units from 10 units and use 8 units. Studies have shown that too rapid reduction in insulin dose can cause persistent severe hyperglycemia and ketonuria. ⚠ Double the dose of NPH and insulin aspart (choice D) is incorrect. This reasoning is based on the wrong assumption, that the patient is not receiving enough insulin treatment but the symptoms of hypoglycemia he experiences in the night suggest the contrary. ⚠ No change in treatment, eat some sugar if sweating develops in the night (choice E) is incorrect. This management has been associated with even higher and longer-lasting morning hyperglycemia. 🔖Key point: Morning hyperglycemia following hypoglycemia in a type I diabetes patient treated with NPH insulin suggests Somogyi's effect. The best management is to replace the insulin therapy with long-acting insulin such as glargine or detemir

🇨🇦 MCCQE1,2 | #Case_107 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 15-year-old white male is brought to your department by his mother because he has been waking up at night "drenched in sweat". This usually occurs between midnight and 1 am and he goes to bed at 10 pm every night. He also reports that his pre-breakfast blood glucose (at 6 am) is 12.2 mmol/L (220 mg/dL). He was diagnosed with type 1 diabetes mellitus and it is treated with insulin. He takes his insulin therapy as prescribed. An hour or so before bedtime he takes 100 units of insulin, (70 units NPH insulin and 30 units of insulin aspart). What is the best recommendation to manage this patient’s condition? a) Nocturnal hormonal measurements b) Reduce the evening dose of insulin by half c) Replace NPH and insulin aspart with glargine d) Double the dose of NPH and insulin aspart e) No change in treatment, eat some sugar if sweating develops in the night

🇨🇦 MCCQE1,2 | #Case_107 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ E 🔎 Explanation Hyperglycemia is common after a major surgery due to release of counter-regulatory hormones. It has negative effect on morbidity and mortality in post-operative period. Randomized clinical trials have shown that tight control of blood glucose in surgical intensive care units improve outcomes, independent of whether the patient has history of diabetes or not. For this reason, hyperglycemia should be aggressively treated in intensive care setting with insulin infusion (choice E) to maintain blood sugar levels between 7.7 mmol/L and 10 mmol/L. The patient described in the stem is not diabetic but has manifested stress induced hyperglycemia. Glycemic control in this case should be achieved with standard insulin infusion; which is 100 units of insulin in 100ml of 0.9% NaCl. Regular insulin, insulin aspart and insulin glulisine are approved for intravenous use. The rate of insulin infusion is 2 units/hour, for blood glucose in the range of 10-11.1 mmol/L, which is reduced to 1.5 unit/hour when the blood glucose is below 10mmol/L and, 1unit/hour when it is below 8.3 mmol/L. ⚠ Observation and monitoring (choice A) is not appropriate for this situation as the patient’s blood glucose level is high and should be treated. ⚠ Sliding scale regime (choice B), in which dose of subcutaneous regular insulin is adjusted based on intermittent capillary sugar values is not suitable in intensive care setting. Insulin absorption from subcutaneous tissue is unpredictable because of circulatory changes and drugs administered in intensive care. ⚠ Glargine is a long-acting insulin and provides basal insulin requirement. It is not suitable in intensive care setting as it does not treat hyperglycaemic surges, which are common in the setting. Dosing regimen of 12 hours (choice D) or 24 hours (choice C) are both unsuitable. 🔖 Key point: Tight control of blood glucose in surgical intensive care units improve outcomes, independent of whether the patient has history of diabetes or not. For this reason, hyperglycemia should be aggressively treated in intensive care setting with insulin infusion

🇨🇦 MCCQE1,2 | #Case_107 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 62-year-old man underwent coronary artery bypass grafting surgery for triple vessel disease. His past medical history is significant for hypertension for which he receives amlodipine and ramipril. He is not diabetic. His pre-operative glycated haemoglobin was 5.8%. Following the surgery he is shifted to the surgical intensive care unit, where his blood glucose is tested 6-hourly. The second spot sample tested 12 hours postoperatively is 10.4 mmol/L. Which one of the following is the most appropriate management of this patient’s glucose levels? a) Observation and 2 hourly blood sugar monitoring b) Sliding scale regular insulin c) Insulin glargine once in a day d) Insulin glargine 12 hourly e) Insulin infusion

🇨🇦 MCCQE1,2 | #Case_106 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ E 🔎 Explanation The patient has acute suppurative sialadenitis which is caused by coagulase-positive Staphylococcus aureus, Streptococcus pneumoniae, and other bacteria. Sialadenitis creates a painful lump in the gland, and foul-tasting pus drains into the mouth. The patient needs treatment with antibiotics (choice E). ⚠ The patient needs to be treated and observation only (choice A) would be considered negligence. ⚠ Cat scratch disease (choice B) involves the lymph glands, not the salivary glands. ⚠ Tuberculosis (choice C) is a rare cause. ⚠ A CT scan (choice E) may be indicated if there is no improvement, or if a tumor is suspected.

🇨🇦 MCCQE1,2 | #Case_106 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 39-year-old white male is seen in your office with a history of sudden painful swelling of the right parotid gland. He also reports occasional foul taste in the mouth. The patient has a temperature of 38.2°C (100.8°F). The parotid gland is tender on examination. Which one of the following would be most appropriate at this point? a) Observation only b) Asking about pets in the household c) Tuberculin test d) A CT scan e) Antibiotics

🇨🇦 MCCQE1,2 | #Case_105 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ C 🔎 Explanation Chronic radiation proctitis develops months to years after radiation and is characterized by pain with defecation, diarrhea, and sometimes rectal bleeding. On colonoscopy, the mucosa is pale and friable with telangiectases which are sometimes large, multiple, and serpiginous

🇨🇦 MCCQE1,2 | #Case_105 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 75-year-old male complains of pain with defecation, and loose stools. This problem seems to have developed gradually over the last several months. His past medical history includes prostate cancer treated with radiation therapy 5 years ago, hypertension, and osteoarthritis. Medications include hydrochlorothiazide (HydroDIURIL), a Beta-blocker, and acetaminophen. On colonoscopy, no polyps or cancer are found, but the rectal and sigmoid areas show pallor with friability and telangiectasias.The most likely diagnosis is: a) Familial angiodysplasia b) Osler-Weber-Rendu syndrome c) Radiation proctitis d) Late-onset ulcerative colitis e) Sensitivity to acetaminophen breakdown products

🇨🇦 MCCQE1,2 | #Case_104 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ D 🔎 Explanation Benign nocturnal limb pains of childhood (growing pains) occur in as many as one-third of children, most often between 4 and 6 years of age. The etiology is unknown, but the course does not parallel pubescent growth, as would be expected if bone growth was the source of pain. The pain often awakens the child within hours of falling asleep following an active day. The pain is generally localized around the knees, most often in the shins and calves, but also may affect the thighs and the upper extremities. A characteristic history coupled with a normal physical examination will confirm the diagnosis. Reassurance that no additional tests or treatments are necessary and that the condition is self-limiting is the most appropriate response.

🇨🇦 MCCQE1,2 | #Case_104 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 During a preparticipation examination of a 5-year-old male for summer soccer camp, his mother states that he frequently awakens during the night with complaints of cramping pain in both legs, and that he seems to experience this after a day of heavy physical activity. She says that he appears to drag his legs at times, but she has never noticed a definite limp. A physical examination of the hips, knees, ankles, and leg musculature is entirely normal.Which one of the following would be the most appropriate next step in the evaluation and management of this patient? a) Plain films of both hips and knees b) Serum electrolyte levels c) Recommending that he not participate in running sports d) Reassurance, with no activity restrictions or treatment e) Referral to a pediatric orthopedist

🇨🇦 MCCQE1,2 | #Case_103 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ A 🔎 Explanation This presentation is typical of either transient synovitis or septic arthritis of the hip. Because the conditions have very different treatment regimens and outcomes, it is important to differentiate the two. It is recommended that after plain films, the first studies to be performed should be a CBC and an erythrocyte sedimentation rate (ESR). Studies have shown that septic arthritis should be considered highly likely in a child who has a fever over 38.7 degrees C (101.7 degrees F), refuses to bear weight on the leg, has a WBC count 3 > 12^9/L, and has an ESR > 40 mm/hr. If several or all of these conditions exist, aspiration of the hip guided by ultrasonography or fluoroscopy should be performed by an experienced practitioner. MRI may be helpful in cases that are unclear based on standard data, or if other etiologies need to be excluded

🇨🇦 MCCQE1,2 | #Case_103 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 3-year-old male is carried into the office by his mother. Yesterday evening he began complaining of pain around his right hip. Today he has a temperature of 37.6°C(99.7°F), cries when bearing weight on his right leg, and will not allow the leg to be moved in any direction. A radiograph of the hip is normal.Which one of the following would be most appropriate at this time? a) A CBC and an erythrocyte sedimentation rate b) A serum antinuclear antibody level c) Ultrasonography of the hip d) MRI of the hip e) In-office aspiration of the hip

🇨🇦 MCCQE1,2 | #Case_102 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ C 🔎 Explanation The scenario described is suspicious for an occult fracture of the scaphoid bone of the wrist. The mechanism of injury, falling on an outstretched hand with the wrist extended, combined with tenderness in the anatomic snuff box (between the extensor pollicis longus and extensor pollicis brevis tendons) raises the possibility of a scaphoid fracture even if initial radiographs are negative. In order to reduce the potential for serious complications, including vascular necrosis and non-union, it is imperative that both the wrist and the thumb be immobilized. In the case described, a thumb spica splint is the best option initially. It should be worn continuously until a follow-up evaluation, including radiographs, in 1-2 weeks.

🇨🇦 MCCQE1,2 | #Case_102 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 While playing basketball, a 29-year-old male falls on his outstretched hand with his wrist fully extended. He sees you the following day because of diffuse wrist pain and decreased range of motion. The point of maximal tenderness is on the dorsal aspect of the wrist between the extensor pollicis brevis and extensor pollicis longus tendons. There is no visible deformity. Radiographs show no fracture.Which one of the following is the most appropriate initial treatment of this patient? a) A wrist extension splint b) An ulnar gutter splint c) A thumb spica splint d) A short arm cast e) Physical therapy

🇨🇦 MCCQE1,2 | #Case_101 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ D 🔎 Explanation With extensive tubal disease on both the HSG and laparoscopy, operative assistance will be needed in order for an egg to reach the uterine cavity. Due to the tubal disease, GIFT is not possible. ICSI is the treatment of choice for azoospermia and severe oligospermia. The patient is ovulatory based on her basal body temperature chart, so ovulation induction alone is not necessary. IVF with transcervical transfer of the embryo is the optimal treatment for this couple. With blastocyst transfer, the current success rates are above 50%. ⚠ The two tests of tubal function both demonstrate that it is highly unlikely for the egg to successfully transport down the tube. Thus, IUI will be of no benefit, since the sperm and egg will not meet. ⚠ ICSI is used for oligospermic and even some azospermic males to achieve fertilization. ⚠ Again, ovulation induction alone will not be successful if the tubes are blocked bilaterally. ⚠ This technique can only be used if there is tubal patency. The egg and sperm mixture is placed in the distal fallopian tube via laparoscopy. The tubes here are blocked

🇨🇦 MCCQE1,2 | #Case_101 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 35-year-old woman presents to your office. She and her 32-year-old husband have been unsuccessful in their attempts to get pregnant for the last 6 years. He has fathered two children in a prior marriage and has a normal semen analysis. Her basal body temperature chart is biphasic. Her past history notes multiple episodes of chlamydia and gonorrhea. A hysterosalpingogram demonstrates blocked fallopian tubes bilaterally, and a laparoscope notes dense and profuse peritubal and pelvic adhesions, along with bilateral clubbed tubes. The most appropriate fertility treatment would be: a) Intrauterine insemination with husband’s sperm (IUI) b) Intracytoplasmic sperm injection with husband’s sperm (ICSI) c) Gonadotropin induction of ovulation d) In vitro fertilization (IVF) e) Gamete intrafallopian transfer (GIFT

🇨🇦 MCCQE1,2 | #Case_100 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ A 🔎 Explanation Amoxicillin is preferred for the treatment of Lyme disease in children, as well as for pregnant or lactating women. Doxycycline is effective, but should not be used in pregnant women. Macrolides are not considered first-line agents because controlled trails of azithromycin or erythromycin in patients with erthema migrans found a high rate of clinical failure.