Case-based MCQ

🇨🇦 MCCQE1,2 | #Case_38 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 52-year-old man presents to the clinic with history of cough of 2 weeks duration. Cough is non-productive and non-spasmodic. He has received a course of amoxicillin for five days with no relief. There is no history of fever or weight loss. He is non-diabetic and smokes 2 packs a day for past 30 years.There is no abnormality detected on physical examination. His complete blood count is within normal limits and his erythrocyte sedimentation rate (ESR) is 45mm in first hour by Westergren method. Chest CT scan shows a contrast enhancing solitary nodule measuring 2 cm in the inferior lobe of left lung. A chest radiograph done 2 years prior was reported to be normal. What is the most appropriate next step in management of this patient? a) Repeat chest CT scan in 3 months b) Repeat chest CT scan in 6 months c) Biopsy of the lesion d) Mantoux test (Tuberculin test) e) Chest Magnetic Resonance Imaging scan

🇨🇦 MCCQE1,2 | #Case_37 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ A 🔎 Explanation This patient has an upper gastrointestinal bleeding as suggested by the history and nasogastric tube aspiration. Given his underlying condition of liver cirrhosis, the most likely cause of his presentation is esophageal varices, a consequence of portal hypertension. Patients with esophageal varices have a strong tendency to develop bleeding. Because this patient is not currently vomiting, is alert to person, place and time, airways and breathing are not as big of a concern as his hemodynamic instability. The initial management, therefore, should be intravenous normal saline and vasopressin analogues such as terlipressin (choice A). The initial goal is to avoid prolonged hypotension and maintain systolic blood pressure around 100 mmHg, this is also particularly important in preventing renal failure and infection. Vasopressin (terlipressin) has been used in these scenarios for many years. It blunts the increase in portal hypertension induced by volume expansion. It is believed that this effect is achieved by its direct vasoconstrictor activity on splanchnic arterioles and precapillary sphincters, with secondary reduction in portal venous blood flow and variceal pressure. Its side effects include increased peripheral vascular resistance, reduced cardiac output, and decreased coronary blood flow. Studies have shown that these side effects are best prevented by the use of vasopressin in combination with glyceryl trinitrate. ⚠ Octreotide and selective decompressive shunts (choice B) is incorrect. Octreotide is considered the first step in management of hemodynamically stable patients. While a surgical shunt provides better control of rebleeding when compared to the combination therapy of beta-blocker and endoscopic variceal ligation, it would not be the best next step in the management of this patient. ⚠ Norepinephrine and endoscopic sclerotherapy (choice C) is incorrect. Endoscopic sclerotherapy is a secondary prophylaxis performed at weekly intervals to prevent bleeding. This patient needs to be stabilized first. ⚠ Propranolol and omeprazole (choice D) is incorrect. Propranolon and nadolol significantly reduce the risks of bleeding and are used as prophylaxis against esophageal varices bleeding, but they have no role in a patient with acute bleeding. Omeprazole is beneficial in patients treated with endoscopic variceal ligation who develop ulcers as complications; it has no role in the management of acute variceal bleeding. ⚠ Normal saline and devascularization of lower esophagus (choice E) is incorrect. While normal saline would be a good initial step in management, devascularization of lower esophagus is rarely performed and is reserved for patients with portal and splenic vein thrombosis who are not suitable candidates for shunt procedures and who continue to have variceal bleeding despite endoscopic and pharmacologic treatment. ✅Key point: Portal hypertension is associated with esophageal variceal bleeding. Patients who present with significant bleeding and hemodynamic instability should first be managed with intravenous normal saline and vasopressin analogues.

🇨🇦 MCCQE1,2 | #Case_37 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 49-year-old male is brought to the emergency department by his son after three episodes of vomiting bright red blood. He says that he has vomited “quite large amounts” though he is not sure he can specify the quantity. He denies dark stool, blood in stool, or diarrhea. He has not vomited since he arrived at the emergency department. He had never had a similar episode in the past. He was diagnosed of liver cirrhosis 2 years ago secondary to alcoholic liver disease.The patient is alert to person, place, and time. His vital signs are temperature 37.4°C, blood pressure 85/60 mmHg, pulse 120 bpm, and respirations 20/min. His abdomen is dull to percussion. A nasogastric tube is inserted, and bright red blood is found when stomach contents are aspirated. Which of the following are the most appropriate next steps in management of this patient? a) Intravenous normal saline and terlipressin b) Octreotide and selective decompressive shunts c) Norepinephrine and endoscopic sclerotherapy d) Propranolol and omeprazole e) Normal saline and devascularization of lower esophagus

🇨🇦 MCCQE1,2 | #Case_36 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ D 🔎 Explanation This patient is known to abuse narcotics and is complaining of severe abdominal pain that radiates to the groin, has elevated blood pressure, tachycardia, tachypnea, and microscopic hematuria. The combination of these symptoms, vital signs, and dipstick findings is unlikely to be a product of malingering. Therefore, at this point, the presumptive diagnosis of nephrolithiasis should be considered and the patient should receive analgesia just as any other patient who is not a narcotic abuser would. The most appropriate next step in management is to offer high dose analgesics (choice D). ⚠ Tell the patient that without physical examination you won’t be able to treat him (choice A) is incorrect. The severity of this patient’s pain is most likely real and based on other findings, it would be inappropriate to refuse giving pain relief to this patient. ⚠ Tell the patient that he is going to be taken to the radiology room for abdominal CT scan (choice B) is incorrect. This patient is unlikely to tolerate being taken for abdominal CT scan until his pain is controlled. It is unethical to prolong the patient’s excruciating pain when it is almost obvious that he is suffering from renal colic. ⚠ Tell the patient that he is going to have an abdominal ultrasound to diagnose his condition (choice C) is incorrect. The most appropriate next step is to alleviate the patient’s pain before doing any imaging study. ⚠ Give oral codeine as it has less potential for abuse until you determine the diagnosis (choice E) is incorrect. While codeine is a low potency opioid with less potential for abuse, it is used for mild and moderate pain and is not the best option for this patient’s excruciating pain. According to the WHO pain ladder for guidance on correct use of analgesics, they should be prescribed according to pain intensity as evaluated by a scale of intensity of pain. This patient should be given analgesics based on his own perception of the pain and not the healthcare staff’s perception of the pain. ✅Key point: A patient (whether a drug-addict or not) in severe pain, such as renal colic, should receive pain treatment with high dose high potency opioid

🇨🇦 MCCQE1,2 | #Case_36 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 28-year-old male who is known by your department for heroin abuse presents with complaints of severe abdominal pain that radiates to the groin. He has elevated blood pressure, tachycardia, tachypnea, and microscopic hematuria. He appears in acute distress, has no visible trauma, and refuses physical examination because of the extreme pain. Which of the following options is the best next step in the management of this patient? a) Tell the patient that without physical examination you won’t be able to treat him b) Tell the patient that he is going to be taken to the radiology room for abdominal CT scan c) Tell the patient that he is going to have an abdominal ultrasound to diagnose his condition d) Offer the patient high dose analgesics despite the fact that he is a narcotic abuser e) Give oral codeine as it has less potential for abuse until you determine the diagnosis

🇨🇦 MCCQE1,2 | #Case_35 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ B 🔎 Explanation This patient’s symptoms of fever, headache, and photophobia combined with the findings on physical examination like nuchal rigidity and petechial rash are suggestive of meningococcal meningitis. In meningococcal meningitis caused by Neisseria meningitidis, above 60% of adult patients have petechial rash, which is a distinctive finding from meningitis caused by other infectious agents.Laboratory examination of the CSF is the best way to confirm the diagnosis of meningitis. In a case of bacterial meningitis it is established by: 🔹Increased opening pressure ( > 180 mm water) 🔹Pleocytosis of polymorphonuclear leukocytes (white blood cell counts between 10 and 10,000 cells/mm³, predominantly neutrophils above 60%) 🔹 Decreased glucose concentration ( < 45 mg/dL) 🔹Increased protein concentration ( > 45 mg/dL) Neisseria meningitidis, which is the most likely infectious agents in this case, is a gram-negative diplococcus; this makes WBC 2500/mm³ with 85% neutrophils; glucose 35 mg/dL; protein 70 mg/dL; Gram negative diplococcus (choice B) the CSF findings most consistent with this patient’s condition. ⚠ WBC 5/mm³ with 60% neutrophils; glucose 55mg/dL; protein 75 mg/dL (choice A) shows normal cell count, normal glucose, and elevated protein, which is known as cyto-albuminological dissociation, a finding most likely linked with Guillain-Barré syndrome. ⚠ WBC 500/mm³ with 80% lymphocytes; glucose 55mg/dL; protein 70 mg/Dl; Herpes simplex virus DNA (choice C) shows what would be found in herpes simplex virus encephalo-meningitis. This patient’s condition is most likely caused by Neisseria meningitidis. ⚠ WBC 3000/mm³ with 90% neutrophils; glucose 30 mg/dL; protein 75 mg/dL; Gram positive cocci (choice D) would be consistent with Streptococcus pneumonia meningitis. It is the most common cause of bacterial meningitis and the risks are increased in children aged between 1 year and 5 years of age and adults older than 55-65 years. College-age adults who live in dormitories are at increased risk of Neisseria meningitidis infection and this patient’s petechial rash in addition to other aspects of his clinical presentation is pathognomonic for meningococcal meningitis. ⚠ WBC 1000/mm³ with 85% lymphocytes; glucose 55 mg/dL; protein 65 mg/dL; Cryptococcal antigen (choice E) would be most consistent with Cryptococcus meningitis, which is more likely to occur in immunocompromised patients such as those affected with AIDS. ✅Key point: Symptoms of fever, headache, photophobia and physical examination of nuchal rigidity and petechial rash are suggestive of meningococcal meningitis. CSF studies show elevated WBC with neutrophil predominance, elevated protein, decreased glucose, and the presence of gram-negative diplococcus

🇨🇦 MCCQE1,2 | #Case_35 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 20-year-old male college student presents to your department with complaints of fever and headache for 2 days. While in the office he mentions that the light is very disturbing to his eyes.Vital signs are: temperature 39.2°C, BP 115/65 mmHg, heart rate 85 bpm, and respirations 16/min. Petechial rash is noted on the patient’s legs and arms. Nuchal rigidity is also observed. Which of the following CSF findings are most likely to be consistent with this patient’s condition? a) WBC 5/mm³ with 60% neutrophils; glucose 55mg/dL; protein 75 mg/dL b) WBC 2500/mm³ with 85% neutrophils; glucose 35 mg/dL; protein 70 mg/dL; Gram negative diplococcus c) WBC 500/mm³ with 80% lymphocytes; glucose 55mg/dL; protein 70 mg/dl; Herpes simplex virus DNA d) WBC 3000/mm³ with 90% neutrophils; glucose 30 mg/dL; protein 75 mg/dL; Gram positive cocci e) WBC 1000/mm³ with 85% lymphocytes; glucose 55 mg/dL; protein 65 mg/dL; Cryptococcal antigen

🇨🇦 MCCQE1,2 | #Case_34 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ C 🔎 Explanation The patient is most likely suffering from autonomic neuropathy causing gastroparesis which most commonly presents with anorexia, nausea, vomiting, abdominal bloating and early satiety. The best management for this condition is to take small frequent meals, improve glycemic control and take metoclopramide (choice C). ⚠Cisapride (choice A) is a serotonin agonist drug that is very effective for gastroparesis but it is not recommended initially. It is advised in resistant cases because it can increase the risk of cardiac arrhythmias. ⚠Domperidone (choice B) is a prokinetic and antiemetic drug that may be used for gastroparesis; however, it is much less effective than metoclopromide. ⚠ Omeprazole (choice D) and H. pylori treatment (choice E) would be appropriate for peptic ulcer disease not gastroparesis

🇨🇦 MCCQE1,2 | #Case_34 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 70-year-old female patient comes to your office complaining of nausea and early satiety of two months duration. Every time she eats, she feels bloated rapidly, she nauseates and sometimes vomits. She denies any pain in the abdomen or any heartburn symptoms. Her past medical history is significant for diabetes mellitus diagnosed 20 years ago. She stopped the oral hypoglycemic drugs 2 years ago and began taking insulin regularly.Her vital signs are within normal limits and the physical exam is unremarkable. What is the most appropriate next step in he management of this patient? a) Cisapride b) Domperidone c) Metoclopramide d) Omeprazole e) Triple antibiotics for H. pylori

🇨🇦 MCCQE1,2 | #Case_33 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ C 🔎 Explanation This patient is a female and is presenting with primary amenorrhea, as she has passed age 16 without menses while having some secondary sexual characteristics present. The differential diagnosis in a phenotypically female patient with absent uterus, breasts, and primary amenorrhea is Mülerian agenesis and androgen insensitivity. Given the description of this patient’s genitalia of a labio-scrotal fusion, an androgen insensitivity grade 3-4 on Quigley scale is more likely (also known as partial androgen insensitivity). The most appropriate studies to confirm the diagnosis would be serum testosterone, dihydrotestosterone, and karyotype (choice C). If the patient has male-appropriate testosterone levels, a diagnosis of androgen insensitivity would be even more likely and this would be finally confirmed with a 46 XY karyotype. On the other hand, if the patient has female-appropriate testosterone levels, a diagnosis of Mülerian agenesis would be likely and this would be confirmed with a 46 XX karyotype. ⚠ Serum follicle-stimulating hormone (FSH) and karyotype (choice A) is incorrect. Serum FSH should be ordered in the work up of amenorrhea when the uterus is present and pregnancy tests are negative. High FSH levels would suggest conditions such as Turner syndrome, which would be confirmed with karyotype and low FSH would suggest conditions such as Kallman syndrome and would be confirmed with a brain MRI. ⚠ Serum 17-hydroxyprogesterone and urinary pregnanetriol (choice B) are very significant in the diagnosis of congenital adrenal hyperplasia of 21-hydroxylase deficiency. In addition to ambiguous genitalia, patients with this condition have abnormal blood pressure, potassium, and sodium. ⚠ MRI urography and follicle-stimulating hormone (choice D) is incorrect. While MRI urography is important in the work up of Müllerian agenesis, at this point, the best studies should also include the possibility of androgen insensitivity. Follicle-stimulating hormone measurements would be the wrong choice. ⚠Serum 5-alpha reductase and brain MRI (choice E) is incorrect. While 5-alpha reductase deficiency presents with ambiguous genitalia with some characteristics similar to what is described in this patient, at this point karyotype and serum testosterone levels measurements would be more inclusive in exploring possibilities presented by the differential diagnosis. Brain MRI is clearly the wrong choice in the work up of this patient. ✅Key point: Ambiguous genitalia is a disorder of sexual development with a wide range of differential diagnosis. In a phenotypically female with developed breasts, absent uterus, and amenorrhea, the differential diagnosis includes Mülerian agenesis and androgen insensitivity. Appropriate tests to distinguish the two are testosterone level measurements and karyotype.

🇨🇦 MCCQE1,2 | #Case_33 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 17-year-old female presents with her mother to the general hospital stating that she has yet to have menses. They report that during the patient’s childhood some genital abnormalities were found, but after appropriate counseling they chose to wait until adolescence “brought some clarification” before taking any further steps in management. Her breasts began to develop at the age of 13.Her vital signs are 110/65mmHg, temperature is 37.2°C, heart rate is 85 bpm, and respirations are 15/min. Her BMI is 19 kg/m², she lacks pubic and axillary hair, and breasts exhibit Tanner stage IV development. External genitalia examination demonstrates an enlarged clitoris, a rugose labia, and a bifid scrotum but no uterus is found on ultrasound. This patient’s diagnosis would be best confirmed by which of the following studies? a) Serum follicle- stimulating hormone and karyotype b) Serum 17-hydroxyprogesterone and urinary pregnanetriol c) Serum testosterone, dihydrotestosterone, and karyotype d) MRI urography and follicle-stimulating hormone e) Serum 5-alpha reductase and brain MRI

🇨🇦 MCCQE1,2 | #Case_32 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ E 🔎 Explanation Starvation (choice E) is unlikely to play a role in the etiology of the acid-base disturbance in this patient. The high pH, low PaCO2 and the appropriately low [HCO3-] point towards compensated respiratory alkalosis. On the other hand, starvation is usually associated with metabolic acidosis due to accelerated fatty acid metabolism, which results in accumulation of ketoacids. If metabolic acidosis were superimposed on respiratory alkalosis in this patient, [HCO3-] would be even lower for the PaCO2 reported. ⚠ High body temperature as in fever (choice A) is known to stimulate ventilation, which will washout CO2 resulting in respiratory alkalosis. This results from direct effect of high core temperature on the medullary respiratory center. ⚠ Chest pain (choice B) is known to stimulate ventilation and washout CO2 resulting in respiratory alkalosis. Pain does this by stimulating sensory afferents in the chest that project to high cortical centers which modulate ventilation. ⚠ Low PaO2 (choice C) stimulates ventilation through peripheral chemoreceptors. This would washout CO2 and cause respiratory alkalosis. The response of ventilation to PaO2 becomes more effective when pressure drops below 60mmHg. ⚠ Salicylate ingestion (choice C) is a likely contributory factor to the etiology of respiratory alkalosis in this patient. Salicylates are known to directly stimulate the respiratory center resulting in increased ventilation and washout of CO2. This is the reason why respiratory alkalosis is an early sign of salicylate poisoning. ✅Key point: Respiratory alkalosis can be caused by common factors like fever, chest pain, and hypoxemia or drugs like salicylates

🇨🇦 MCCQE1,2 | #Case_32 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 One week after diagnosis, a patient with rheumatoid arthritis was brought to hospital with chest pain, fever, and nausea. He indicated that his last meal was about 24 hours ago and that he is on Aspirin 600mg 4-hourly. Physical examination showed the following: heart rate 88 beat per minute, respiratory rate 23 per minute, blood pressure 125/65 mmHg and body temperature 38.1°C. Chest examination revealed signs suggestive of pneumonia. No joint swelling could be demonstrated and the rest of physical examination was normal. With appropriate work-up, myocardial infarction was excluded and pneumonia was diagnosed. Blood gas analysis was as follows: pH 7.50 PaO2 67mmHg PaCO2 25mmHg [HCO3-] 19mmol/L Which of the following factors is least likely to play a role in the etiology of the acid-base disturbance in this patient? a) Fever b) Chest pain c) Low PaO2 d) Salicylate ingestion e) Starvation

🇨🇦 MCCQE1,2 | #Case_31 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ A 🔎 Explanation Carcinoid syndrome is the most likely diagnosis of the patient’s condition. Carcinoid syndrome is characterized by: flushing episodes, diarrhea, wheezing and right sided cardiac valvular lesions caused by the released hormones, especially serotonin. Any patient presenting with an unexplained flushing and diarrhea should be tested for urine 5-HIAA (5- hydroxyinolacetic acid) (choice A). This is a very sensitive and specific test. ⚠ 24-hour urine cortisol (choice B) would be appropriate if Cushing’s syndrome is suspected. ⚠24-hour urine vanillymandelic acid and catecholamines levels (choice C) would be appropriate if pheochromocytoma is suspected. ⚠Although it is highly specific, blood serotonin level (choice D) is not a sensitive as the blood level fluctuates constantly; thus, should not be ordered initially. ⚠ Insulin, glucose and C-peptide serum level (choice E) would be appropriate if insulinoma is suspected.

🇨🇦 MCCQE1,2 | #Case_31 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 35-year-old male patient presents to your office complaining of flushing episodes. These episodes occur several times per day, without any apparent trigger and last for a few minutes. During these episodes, his skin becomes extremely red with burning sensation. The patient states that over the past few weeks, he had watery diarrhea, few times a day, associated with severe abdominal colic. The past medical and surgical history is otherwise normal.On physical examination, the patient appears comfortable. Vital signs: Temp of 37°C, BP is 130/85 mmHg, pulse is 80/min and respiratory rate is 14/min. Occasional wheezes are heard on lung auscultation. The abdomen is soft and non tender with hyperactive bowel sounds. Which of the following is the best initial test to order for this patient? a) 24-hour urine 5-HIAA (5-hydroxyindolacetic acid) b) 24-hour urine cortisol c) 24-hour urine vanillymandelic acid and catecholamines levels d) Blood serotonin level e) Insulin, glucose and C-peptide serum level

🇨🇦 MCCQE1,2 | #Case_30 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ B 🔎 Explanation Hyperventilation syndrome is typically a disease of young women. It usually presents with tachypnea and hyperpnoea, which may be interpreted as breathlessness, atypical chest pain, agitation, dizziness, and palpitations. Physical examination shows tachypnea and sometimes wheezes. If severe, carpopedal spasm might develop. Blood gas analysis of patients with hyperventilation syndrome usually shows respiratory alkalosis. Our patient showed most of these features and hyperventilation syndrome (choice B) is thus, the most likely diagnosis in this patient. ⚠ Acute Bird Fancier Pneumonitis (choice A) is a rather unlikely cause of symptoms, and blood gas results in this patient despite the history of pigeon breeding. Acute Bird Fancier Pneumonitis typically presents with breathlessness, fever with chills, cough, and malaise. These symptoms develop 4 to 6 hour following exposure. Physical examination of patients with this disease usually shows diffuse crackles over the lower lung fields. When patients with Bird Fancier Pneumonitis or any other form of interstitial lung disease have low PaCO2, PaO2 will also be low due to ventilation perfusion mismatch. This mismatch causes hypoxemia (low paO2) which stimulates ventilation washing out CO2. Our patient did not show most of these features and Bird Fancier Pneumonitis is thus, an unlikely in this patient. ⚠ Anemia (choice C) is an unlikely cause of symptoms, and blood gas results in this patient. Only severe anemia (hemoglobin below 80g/L) can stimulate ventilation and result in respiratory alkalosis. Because of their high blood flow, the peripheral chemoreceptors cover their oxygen need from the dissolve fraction of oxygen in blood, which primary depends on PaO2 rather than hemoglobin level. Anemia in our patient is mild and is thus, unlikely to explain symptoms in this patient. ⚠ Panic attack (choice D) is a discrete period of intense fear or discomfort in which four of 12 criteria should prevail. For the diagnosis of panic disorder to be made, one attack should be followed by one month or more of persistent concern about having additional attacks or a significant change in behaviour related to the attacks. Although, panic attacks can cause hyperventilation, one cannot make the diagnosis of panic disorder in this patient. ⚠ Like other benzodiazepines, flurazepam (choice E) is used in the treatment of hyperventilation syndrome because it can alleviate anxiety and suppress ventilation. ✅Key point: In young patients with normal physical examination and absence of hypoxemia, hyperventilation is most likely due to hyperventilation syndrom

🇨🇦 MCCQE1,2 | #Case_30 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 26-year-old woman was brought to hospital with sudden onset breathlessness, agitation, central chest pain, and dizziness. For the last two weeks she has been on flurazepam for insomnia. She loves pigeons and she tends to a couple of them at home. On examination, her heart rate was 97 beats per minute, respiratory rate 26/minute, blood pressure 124/82 mmHg, and body temperature 36.9°C. Physical examination was normal. Myocardial ischemia was excluded with appropriate work-up. Complete blood count was normal apart from a hemoglobin level of 110g/L. Blood gas analysis was as follows: pH: 7.62 PaO2: 118 mmHg PaCO2: 20 mmHg [HCO3-]: 20 mmol/L Which of the following is the most likely cause of the symptoms and blood gas results in this patient? a) Acute Bird Fancier Pneumonitis b) Hyperventilation syndrome c) Anemia d) Panic disorder e) Flurazepam ingestion

🇨🇦 MCCQE1,2 | #Case_29 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ E 🔎 Explanation Syndesmotic (high ankle) sprains account for as many as 11% of ankle sprains. The mechanism of injury is dorsiflexion and/or eversion of the ankle, most commonly in contact sports. The syndesmotic structures include the anterior, posterior, and transverse tibiofibular ligaments, as well as the interosseous membrane. These injuries can cause chronic ankle instability, resulting in recurrent sprains and hypertrophic ossification. The diagnosis can be made by several tests. The squeeze test can be performed by compressing the fibula against the tibia at mid-calf. A positive test occurs when this elicits pain in the region of the anterior tibiofibular ligament. A positive external rotation stress test causes pain at the same site. It is performed by stabilizing the leg and externally rotating the foot. The crossed-leg test can also detect this injury. The patient places the involved ankle on the opposite knee and pressure is applied to the medial side of the involved ankle, which causes pain at the syndesmosis.While ankle support is often useful for less serious sprains, a Cochrane review showed that semirigid supports are better than elastic bandages. Therapeutic ultrasound has not been shown to have any value for ankle sprains. The injury can be confirmed with an MRI. Indications for referral to an orthopedic surgeon include fracture, dislocation or subluxation, syndesmotic injury, tendon rupture, and uncertain diagnosis

🇨🇦 MCCQE1,2 | #Case_29 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 A 16-year-old male comes to your office after suffering an eversion injury to his ankle while being tackled in a football game 3 days ago. He was not able to bear weight after the injury and now has tenderness at the distal tibiofibular joint with no swelling. Compression of the fibula against the tibia at the mid-calf elicits pain anterior to the lateral malleolus and proximal to the ankle joint. Stabilizing the leg and rotating the foot externally elicits pain at the same location. Radiographs are negative. Which one of the following would be most appropriate at this point? a) Application of an elastic wrap to the ankle for 2 weeks b) Therapeutic ultrasound c) Stress radiographs d) A CT scan e) Long-term semirigid support

🇨🇦 MCCQE1,2 | #Case_28 | #answer 〰〰〰〰〰〰〰〰〰〰〰〰〰〰 ✅ D 🔎 Explanation A history of mechanical ventilation, especially in addition to underlying lung pathology, and a physical exam showing absent breath sounds on one side of the chest suggests a diagnosis of tension pneumothorax. This patient is hypotensive, tachycardic, and tachypneic, so this is a medical emergency. Before any other imaging or intervention is attempted, an immediate needle thoracostomy performed by inserting a 16-18 gauge needle into the 2nd intercostal space (choice D) of the affected side is required to treat this patient. Once this has been accomplished, a rush of air out of the pleural space is expected. Following needle thoracostomy, a chest tube can be inserted, and chest C-ray can be performed. ⚠ Obtaining a chest CT (choice A) would be inappropriate at this time, as this patient is clinically unstable (hypotension, tachypnea, tachycardia), and needs immediate treatment. In the context of a pneumothorax, a chest CT can be used if there is clinical uncertainty, and the patient is stable. ⚠ Obtaining a chest X-ray (choice B) does need to be done, but the first step is needle thoracostomy. Had a chest X-ray been performed, it would have shown deviation of the trachea to the right (the side opposite of the pneumothorax), as well as increased radiolucency on the left side of the chest. ⚠ Inserting a chest tube into the 5th intercostal space in the midaxillary line (choice c) should be done after the initial needle thoracostomy, as the needle decompression can cause a simple pneumothorax which can be treated with chest tube insertion. When a chest tube is inserted, it should be inserted above the rib, as the neurovascular bundle can be struck if insertion occurs below the rib. ⚠ Pericardiocentesis - inserting a needle under the xiphoid process, upward and leftward (choice E) is incorrect, as this patient does not have cardiac tamponade. The diagnosis of tamponade would require hypotension, decreased heart sounds, and distended neck veins, as well, lungs should be clear to auscultation, which are not seen in this patient. ✅Key point: Sudden onset of chest pain and decreased or absent breath sounds on one side suggest tension pneumothorax. The first step in treatment is insertion of a large-gauge needle into the second intercostal space of the affected side