A 40-year-old man is evaluated for palpitations in the emergency department. He has had these symptoms several times over the past year but this episode is worse. He denies any associated chest pain, lightheadedness, or syncope. He denies any history of medical problems and takes no medications. Examination reveals an adult male in no significant distress. Cardiac examination is significant for regular tachycardia with no jugular venous pressure elevation. Lungs are clear without crackles or wheezing. There is no lower extremity edema. ECG shown below. What is the best intervention at this point?


A. Valsalva maneuver
B. Adenosine
C. Metoprolol
D. Digoxin
E. Cardioversion

The correct answer is A.

Supraventricular tachycardias (SVT) include paroxysmal, reentry, or preexcitation tachycardias. Reentry SVTs include AV nodal reentry (AVNRT), atrioventricular reentry, or atrial reentry. Reentry circuits require the presence of at least two different conduction pathways with differential refractory times. It is characterized by an abrupt onset and termination of tachycardia, that distinguishes it from sinus tachycardia, which has gradual changes in rate. It is precipitated by a premature atrial or ventricular contraction or hyperadrenergic state. Other triggers include hyperthyroidism and stimulants, including caffeine, drugs, and alcohol. This patient has supraventricular tachycardia (SVT) likely related to atrioventricular nodal reentrant tachycardia (AVNRT) and he has no concerning symptoms.

The ECG shows a regular, fast rhythm with absent P waves and a narrow QRS complex. Unstable patients require immediate synchronized cardioversion. Stable patients, such as the patient above, should first undergo vagal maneuvers. Some common vagal maneuvers include holding your breath and bearing down (Valsalva maneuver), coughing, gagging, and immersing your face in ice-cold water. If vagal maneuvers are unsuccessful, adenosine is used both diagnostically and therapeutically. Adenosine transiently blocks the AV-node and allows the circuit to “reset.”


⚠Choice B is not correct:

Adenosine is very short acting and can be used if vagal maneuvers fail to terminate the arrhythmia.

⚠Choice C is not correct:

Metoprolol would also be considered if the above measures failed.

⚠Choice D is not correct:

Digoxin would also inhibit the AV node but has more potential side effects than the other medications and is rarely used for this purpose.

⚠Choice E is not correct:

Cardioversion would be reserved for hemodynamic instability including hypotension, heart failure, or angina.

Summarized Points:

This patient has SVT likely related to AVNRT and he has no concerning symptoms. The initial attempts at termination should use vagal maneuvers such as the Valsalva maneuver.

A 36-year-old life-long asthmatic has repeated episodes of asthma exacerbation accompanied by fever and thick brownish sputum that respond to oral prednisone therapy. His leukocyte count is 8,500/µL with 15% eosinophils. Chest x-ray reveals bronchiectasis on the left side. Which of the following is the best next step in the management of this patient?

A. Bronchoscopy with bronchoalveolar lavage
B. Immunoglobulin levels to evaluate for immunodeficiency
C. Induced sputum for Pneumocystis jirovecii
D. Purified protein derivative test
E. Aspergillus skin testing

This patient with known asthma has recurrent exacerbations with fever and expectoration of dark brown mucus, which is suggestive of allergic bronchopulmonary aspergillosis (ABPA). Patients may experience additional systemic symptoms (e.g., anorexia, malaise, or weight loss) or have hemoptysis. ABPA is caused by hypersensitivity to bronchial colonization by Aspergillus fumigatus. It occurs more commonly in asthmatics and patients with cystic fibrosis. Proteolytic enzymes and mycotoxins induce an intense inflammatory reaction that can eventually cause bronchiectasis and fibrosis. Early diagnosis is important as the onset of bronchiectasis is associated with poor outcomes. Diagnosis is based on clinical and radiographic features and immunologic testing. Immediate cutaneous hypersensitivity to skin prick testing is a characteristic finding. If negative, intradermal reactivity may be tested for confirmation. A negative skin prick test and intradermal reactivity excludes the diagnosis. If positive, immunologic testing is performed. High-resolution CT characteristically shows infiltrates, central bronchiectasis, and mucus-filled bronchi (mucoid impaction). A positive bronchodilator response on pulmonary function tests is only seen in about 50% of patients. Treatment involves a combination of corticosteroids and antifungal agents (e.g., itraconazole).

⚠ Choice A is not correct:

Bronchoalveolar lavage specimens may show Aspergillus species. However, the test is more invasive and is usually not indicated.

⚠ Choice B is not correct:

Common variable immunodeficiency (CVID) can present with recurrent pulmonary infections and bronchiectasis, but it does not cause recurrent asthma exacerbations responsive to steroids.

⚠ Choice C is not correct:

Induced sputum for Pneumocystis jirovecii may be helpful to diagnose Pneumocystis pneumonia in an asthmatic taking high-dose chronic oral steroids. However, this patient was only on intermittent steroids.

⚠ Choice D is not correct:

Patients with tuberculosis may also present with chronic cough and constitutional symptoms, but these are progressive (not intermittent) and do not respond to steroids.

Summarized Points:

Allergic bronchopulmonary aspergillosis is a hypersensitivity reaction to Aspergillus that may colonize the airways of patients with asthma and cystic fibrosis. It presents with worsening asthma symptoms, fever, fleeting infiltrates, pleuritic chest pain, and peripheral eosinophilia. The first step in diagnosis is Aspergillus skin testing. If left untreated, the disorder can result in bronchiectasis with a poor prognosis.

A 49-year-old female presents to the emergency department with complaint of severe epigastric and right upper quadrant (RUQ) abdominal pain. Her symptoms started 3 days ago but have progressively worsened over the past 12 hours. Her symptoms are worse with meals. She has had two episodes of vomiting in the past 12 hours and is nauseous currently. Past medical history is significant for diabetes, osteoarthritis, and hypertension. Her blood pressure is 146/80 mmHg, pulse is 110/min, respiratory rate is 16/min, temperature is 39 C (102.3 F). On physical examination, there is severe right upper quadrant pain on deep palpation, most pronounced on palpation after deep inspiration. Bowel sounds are diminished. The patient is lying on her side holding an emesis basin. Which of the following is causing this patient’s disorder?

A. Alcoholic liver disease
B. Gallstone obstruction in the cystic duct
C. Obstruction from carcinoma of the head of the pancreas
D. Gallstone obstruction in the common bile duct
E. Pancreatic inflammation

The correct answer is B.

The patient in this question is presenting with acute cholecystitis. He is presenting with fever, right upper quadrant pain after a fatty meal that radiates to the right scapula, and positive Murphy sign (pain on palpation in the right upper quadrant with cessation of inspiration). Additional nonspecific findings include vomiting, leukocytosis, and mild elevation in transaminases. Acute cholecystitis usually arises from gallstone formation that obstructs the cystic duct. The symptoms occur after eating a fatty meal because the fat stimulates gallbladder contraction, and in the presence of cystic duct obstruction, this leads to colicky pain. Infection results from stasis that contributes to bacterial growth in the gallbladder.

⚠Choice A is not correct:

Alcoholic liver disease does not present with this constellation of symptoms.

⚠Choice C is not correct:

Similar to common bile duct obstruction, obstruction from a carcinoma of the head of the pancreas would cause severely elevated alkaline phosphatase levels and would normally present with weight loss and painless jaundice.

⚠Choice D is not correct:

Importantly, alkaline phosphatase is not elevated in this patient with acute cholecystitis. Assume if laboratories are not shown, they are normal. If it were elevated (in addition to total bilirubin and direct bilirubin), this might indicate common bile duct obstruction in the setting of jaundice (choledocolithiasis).

⚠Choice E is not correct:

Pancreatitis should definitely be ruled out with a lipase check, but pain typically is only epigastric in nature and radiates to the back.

Summarized Points:

acute cholecystitis presents with fever, right upper quadrant pain after a fatty meal that radiates to the right scapula, and positive Murphy sign (pain on palpation in the right upper quadrant with cessation of inspiration). Usually caused by gallstone formation that obstructs the cystic duct.

A 6-year-old girl is brought to the physician for a routine examination. She has no complaints and is enjoying first grade. Her favourite drink is orange juice, and she enjoys chips and cookies. The girl has no medical problems and takes no medications. The review of the systems is negative. Several maternal relatives are obese, but no family members have heart disease or stroke. There are no smokers in the home. Body mass index (BMI) was previously in the 80th percentile but is now in the 99th percentile. Vital signs are normal. Examination reveals central adiposity. No acanthosis nigricans is seen. Which of the following is the best next step in the management of this patient?

A. Serum lipid panel
B. 12-lead electrocardiogram
C. Liver ultrasound
D. No testing indicated at this age
E. Serum thyroid function test

The growing prevalence of overweight (body mass index [BMI] 85th–95th percentile) and obese (BMI ≥95th percentile) children has resulted in increasing rates of early dyslipidemia and metabolic syndrome. Children with a BMI ≥95th percentile should undergo fasting glucose testing to screen for diabetes mellitus, serum alanine aminotransferase (ALT) to screen for fatty liver disease, and a serum lipid panel to screen for dyslipidemia. Ideally, total cholesterol, triglycerides, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol are measured after the patient has fasted. Triglycerides in particular can remain elevated for several hours after a high-fat meal, but recent studies show that the other values may not be significantly affected by a recent meal. The first-line treatment for children with elevated LDL and triglycerides includes regular exercise, a healthy diet low in fat and cholesterol, avoiding sugary beverages, and minimizing television time to <2 hours per day. Addressing modifiable risk factors can delay, pause, or reverse the development of these complications.


⚠Choice B is not correct:

Routine electrocardiogram in asymptomatic children with no significant family history of cardiac disease is low yield and not recommended.

⚠Choice C is not correct:

If the serum ALT is elevated, a liver ultrasound can be performed to evaluate for fatty liver disease.

⚠Choice D is not correct:

Testing should be performed to identify potentially treatable complications of obesity.

⚠Choice E is not correct:

Hypothyroidism rarely causes obesity in isolation and usually manifests with other abnormalities (e.g., constipation, cold intolerance, fatigue).

Summarized Points:

Pediatric obesity is increasingly common and is associated with early complications such as dyslipidemia, fatty liver disease, and hypertension. Fasting glucose, serum alanine aminotransferase, and a lipid panel should be measured in these patients. Dietary and lifestyle modifications are the first-line treatment.

A 77-year-old woman was admitted from home because of syncope. Her daughter reports that the patient has been losing weight and rarely eating since the death of her husband about one year ago. In addition, the daughter states that her mother's urine has a dark colour to it and that she is very concerned. He laboratory results are the following:

 Serum chemistry
    Creatinine  247µmol/L (50-90)
    Albumin 21 g/L (35-50)
 Urinalysis
    Blood positive
 

Urine microscopy shows 0-2 WBC and 0-2 RBC. The patient does not have a significant cardiac history, but she has diabetes and takes metformin 1000 mg twice a day. What is the next best step in determining the etiology of her acute kidney injury?

A. Creatinine kinase level
B. Renal ultrasound
C. CT scan with IV contrast
D. Glycated hemoglobin
E. Lactate dehydrogenase level

The correct answer is A.

This patient is suffering from an acute kidney injury (AKI) due to pigment nephropathy from rhabdomyolysis. A urine dipstick test for blood with positive findings in the absence of red blood cells (RBCs) indicates myoglobinuria. This should automatically suggest rhabdomyolysis. A creatine kinase (CK) level can confirm that the patient has rhabdomyolysis from protein/calorie malnutrition. She has been losing weight and is weak, and her albumin level is low, which confirms a decreased oral intake. CK levels rise within 12 hours of muscle injury, peak in 24-36 hours, and decrease at a rate of 30-40% per day. The serum half-life of CK is approximately 36 hours. Total CK elevation is a sensitive but nonspecific marker for rhabdomyolysis. CK levels 5 times the reference range suggest rhabdomyolysis, although CK levels in rhabdomyolysis are frequently 100 times the reference range or even higher.

⚠ Choice B is not correct:

Several studies have shown the benefits of ultrasound in the diagnosis of rhabdomyolysis. However, most consistent data is needed to rely on it as a diagnostic tool.

⚠ Choice C is not correct:

Imaging studies in rhabdomyolysis may show signs of muscle edema and/or hemorrhage. Edematous muscles on CT scan are usually hypodense and possibly enlarged.

⚠ Choice D is not correct:

Glycated hemoglobin, also known as HbA1c, can be used to check the blood sugar levels of prediabetics and monitor blood sugar control in patients with diabetes mellitus. Some studies have shown that elevated HbA1c levels predict acute kidney injury after coronary artery bypass grafting in non-diabetic patients.

⚠ Choice E is not correct:

Aside from creatinine kinase, other muscle enzymes, such as aldolase, aminotransferases, lactate dehydrogenase, may be elevated in rhabdomyolysis. Their presence is not necessary to make the diagnosis.

Summarized Points:

The diagnostic hallmark of rhabdomyolysis is an elevation in serum creatinine kinase (CK) levels. These levels can range from about 1500 to over 100,000 international units/L and usually begin to rise within 2-12 hours following muscle injury and reach a peak within 24-72 hours. Another characteristic finding of rhabdomyolysis is reddish-brown urine from myoglobinuria, which may only be seen 50% of the time.

A 41-year-old woman is evaluated for a 9-month history of Raynaud phenomenon. She reports no difficulty swallowing, dyspnea on exertion, or hand stiffness. She has recently developed gastroesophageal reflux disease. On physical examination, vital signs are normal. The skin between the distal and proximal interphalangeal joints of the fingers is difficult to tent. Three telangiectasias on the right hand and four on the left are noted. She also has two small telangiectasias on the face and one on the inside bottom lip. No digital pitting is seen. Laboratory evaluation reveals a positive antinuclear antibody titer (1:320) and positive anticentromere antibody titer (1:160). Which of the following is the most likely diagnosis?

A. Eosinophilic fasciitis
B. Limited cutaneous systemic sclerosis
C. Diffuse cutaneous systemic sclerosis
D. Mixed connective tissue disease

The correct answer is B.

Anticentromere antibodies (titer of 1:80 or higher) are rare in healthy people. The finding of anti-centromere antibodies (ACAS) in the setting of Raynaud phenomenon is 60% sensitive and 98% specific for limited cutaneous systemic sclerosis (LcSSc), which was previously known as the CREST syndrome. Patients with LcSSc have manifestations that can include calcinosis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia (CREST); all five conditions may not be present. The presence of anticentromere antibodies increases the risk for pulmonary hypertension, which occurs in 20% of these patients. Patients who have only Raynaud phenomenon and ACA must be followed for development of LcSSc This patient with recent onset of Raynaud phenomenon is showing features of LcSSc. Although gastroesophageal reflux disease is common in the general population, the recent onset of telangiectasias and sclerodactyly suggests LcSSc. The telangiectasias seen in LcSSc are matted; these clusters of dilated vessels appear as small pink or red macules that blanch on light pressure. They are most commonly seen on the face, mucous membrane, and hands.

⚠Choice A is not correct:

Eosinophilic fasciitis is associated with orange peel induration (peau d'orange) of proximal extremities, with sparing of hands and face, and the presence of peripheral eosinophilia. The presence of Raynaud phenomenon and the positive ACA result make eosinophilic fasciitis an unlikely diagnosis.

⚠Choice C is not correct:

Patients with diffuse cutaneous systemic sclerosis (DcSSc) have skin involvement that is more extensive than that found in LcSSc and additionally includes the arms, trunk, and lower extremities. Anti-Scl-70 antibodies are generally associated with DcSSc, with a prevalence approaching 30%, and these antibodies are associated with a higher risk for interstitial lung disease. ACM are uncommon in DcSSc.

⚠Choice D is not correct:

Mixed connective tissue disease is a specific overlap syndrome that includes clinical manifestations of at least two of the following: systemic lupus erythematosus, polymyositis, and systemic sclerosis. Positive results for anti-U1-ribonucleoprotein antibodies are the primary laboratory feature in many patients. The absence of findings associated with another connective tissue disease and a positive ACA titer support the diagnosis of LcSSc rather than mixed connective tissue disease.

Summarized Points:

The finding of anticentromere antibodies in the setting of Raynaud phenomenon is 60% sensitive and 98% specific for the development of limited cutaneous systemic sclerosis. Anti-Scl-70 antibodies are generally associated with diffuse cutaneous systemic sclerosis, with a prevalence approaching 30%, and these antibodies are associated with a higher risk for interstitial lung disease.

An 79-year-old woman experiences the sudden onset of lower extremity weakness and collapse on getting out of bed. She has been previously healthy and has not taken any medications. She has no history of back pain. On examination, she is alert and oriented to time, place and date. Her upper extremity sensation and strength are intact. Her legs are weak bilaterally, with loss of pain and temperature sensation and areflexia. Her bladder is distended. Which of the following is the most likely diagnosis?

A. Anterior cerebral artery occlusion
B. Anterior spinal artery occlusion
C. Cauda equina syndrome
D. Guillain-Barré syndrome
E. Thoracic spinal cord compression

The correct answer is B:

The perfusion territory of the anterior spinal artery includes the anterior horn cells and part of the pain and temperature pathways. Thrombosis of this artery causes flaccid paralysis, loss of bowel and bladder function and loss of pain and temperature sensation.


⚠ Choice A is not correct:

Anterior cerebral artery occlusion can cause leg weakness but there should be no sensory loss. Upper motor neuron signs are present in the leg.

⚠ Choice C is not correct:

Cauda equina syndrome can cause flaccid paraplegia but somatic sensation should be compromised since sensory nerve roots are involved in the disease process.

⚠ Choice D is not correct:

Guillain-Barré syndrome rarely develops this acutely. If loss of pain and temperature sensation occurs, it presents with concurrent loss of position and vibration sense.

⚠ Choice E is not correct:

Thoracic cord compression is associated with low back pain and produces upper motor neuron dysfunction in the legs.

Summarized Points:

These patients, typically abruptly present with Anterior Spinal Artery(ASA) syndrome consisting of flaccid paralysis, bowel/bladder dysfunction, sexual dysfunction, possible hypotension, and loss of tendon reflexes. Spasticity and hyperreflexia develop over the subsequent days to weeks. Vibratory and proprioceptive sensation is preserved because posterior circulation of the spinal cord is not affected This patient needs emergent MRI for diagnosis and treatment with supportive care and lumbar drains to reduce spinal pressure.

A 27-year-old farmer presents with a linear vesicular rash on his hands and face, particularly around his left eyelid. He describes the rash as highly itchy. He has no fever, headaches, or nausea. He has had a similar rash as a child but doesn't recall it. He mentioned he was pulling out weeds around the edge of his farm before the rash occurred. Given the suspected diagnosis, which of the following is the most appropriate treatment option for this patient?

A. Skin patch testing
B. Antibiotic treatment targeted at Staph aureus
C. Treatment with jewelweed extract
D. Topical corticosteroid therapy
E. Systemic corticosteroid therapy

Poison ivy causes allergic contact dermatitis due to a type IV hypersensitivity reaction to the plant Toxicodendron radicans, with similar reactions caused by poison oak and poison sumac. The compound urushiol is present in poison ivy and causes a Type IV hypersensitivity reaction in up to 50% of exposed individuals. Although exposure to intact plant parts does not usually cause dermatitis, the toxic oil will contact skin, clothing, pets, or tools through bruised or broken pieces of plants. Urushiol oil passes through the epidermis to be processed by Langerhans cells, activating T lymphocytes to trigger the hypersensitivity reaction. Clinical features include pruritic, erythema, and formation of vesicles, bullae, or plaques presentation in linear arrangement where exposure to urushiol has occurred. Although the rash usually occurs within 4 to 96 hours after exposure in previously sensitized patients, it may develop in some cases up to 3 weeks after exposure. Treatment with systemic corticosteroids is indicated for severe symptoms and when the rash is on the face or genitalia. In other cases, high-potency topical corticosteroids and antihistamines may provide some relief.

⚠ Choice A is not correct:

Skin patch testing isn't as useful clinically at this time as it would look for hypersensitivity reactions to particular triggers. In the story, the clinical history is adequate to diagnose based on the stem and the physical exam findings to proceed with treatment.

⚠ Choice B is not correct:

While there may be secondary infections due to bacteria in areas of skin exposure and damage, of which staph aureus may be a culprit, the clinical stem does not suggest impetigo, so antibiotics are not indicated.

⚠ Choice C is not correct:

Jewelweed extract is not efficacious for treating contact dermatitis due to poison ivy.

⚠ Choice D is not correct:

Treatment with high potency topical corticosteroids is generally appropriate for limited exposure areas. However, given the lesions around his face, particularly around his eyes, systemic steroids are indicated for this patient.

Summarized Points:

Contact dermatitis due to poison ivy, poison oak, and poison sumac are caused by a type IV hypersensitivity reaction to urushiol exposure. While the reaction will dissipate on its own, treatment with steroids can be helpful, and systemic steroids are indicated when areas involved include the face or genitalia

A 55-year-old woman, gravida 1 para 1, comes to the office due to leakage of urine. The patient first noticed intermittent loss of urine a few years ago. The leakage has progressively worsened and now she is constantly leaking a small amount of urine. The patient soaks through a thin incontinence pad 2 or 3 times a day. She has no dysuria, hematuria, or urge to void. The patient has type 1 diabetes mellitus managed with an insulin pump. Her last hemoglobin A1c was 11.6%. At age 30 she had an operative vaginal delivery complicated by a large perineal laceration. Vital signs are normal. Pelvic examination reveals leakage of urine that increases with Valsalva. Postvoid residual volume is increased. There is decreased sensation to light touch and pinprick involving the perineum and both feet. Laboratory results are as follows:

 Urinalysis
  Protein  trace
  Blood  trace
  Urine culture negative
 

Which of the following is the best next step in the management of this patient?


A. Intermittent self-catheterization
B. Pelvic floor muscle exercises
C. Placement of midurethral sling
D. Placement of suprapubic catheter
E. Tolterodine therapy