A 74-year-old gentleman presents to his family practitioner with the complaint of an inability to open his left eye since this morning. He also complains of intermittent pain and numbness in his left arm that has been present for the last few days. He denies ocular pain, difficulty swallowing, fatigability, or diplopia. His symptoms remain constant without fluctuation. He has a history of diabetes mellitus type 2, hypertension, and hypercholesterolemia. Further history reveals that he has lost 5.4 kg (12 lb) of weight in the past 4 months. He is a chronic smoker with a 72 pack-year smoking history. His blood pressure is 142/76 mm Hg, the heart rate is 76/min, the respiratory rate is 12/min, the temperature is 36.8°C (98.4°F), and BMI is the 18.2 kg/m2. The patient is awake, alert, and oriented to person, place, and time. He has partial drooping of the left eyelid while the right eyelid appears normal. The left pupil is 1 mm and the right pupil is 3 mm in diameter. Extraocular muscle movements are normal. What additional clinical feature would most likely be present in this patient?
Q1052
A 68-year-old male is brought to the emergency department by his wife. An hour earlier, he dropped to the floor and began to violently shake his extremities. He urinated on the carpet and seemed confused for several minutes after. He is now feeling better. He has never experienced an episode like this before, nor does he think anyone in his family has. He and his wife are concerned that he has unintentionally lost 22.6 kg (50 lb) in the past 6 months. He has also been experiencing chest pain and has coughed up blood on a few occasions. He has a 50-pack-year smoking history and quit 2 years ago. His temperature is 36.8°C (98.2°F), heart rate is 98/min, respiratory rate is 15/min, blood pressure is 100/75 mm Hg, and his O2 saturation is 100% on room air. The physical exam, including a full neurologic and cardiac assessment, demonstrates no abnormal findings. Edema, ascites, and skin tenting are notably absent. A brain MRI does not indicate areas of infarction or metastatic lesions. ECG is normal. Urine toxicology screen is negative. EEG is pending. Laboratory findings are shown below:
BUN 15 mg/dL N: 7 to 20 mg/dL
pCO2 40 mm Hg N: 35-45 mm Hg
Creatinine 0.8 mg/dL N: 0.8 to 1.4 mg/dL
Glucose 95 mg/dL N: 64 to 128 mg/dL
Serum chloride 103 mmol/L N: 101 to 111 mmol/L
Serum potassium 3.9 mEq/L N: 3.7 to 5.2 mEq/L
Serum sodium 115 mEq/L N: 136 to 144 mEq/L
Total calcium 2.3 mmol/L N: 2-2.6 mmol/L
Magnesium 1.7 mEq/L N: 1.5-2 mEq/L
Phosphate 0.9 mmol/L N: 0.8-1.5 mmol/L
Hemoglobin 14 g/dL N: 13-17 g/dL (men), 12-15 g/dL (women)
Glycosylated hemoglobin 5.5% N: 4%-6%
Total cholesterol 4 mmol/L N: 3-5.5 mmol/L
Bicarbonate (HCO3) 19 mmol/L N: 18-22 mmol/L
What is indicated first?
Q1053
A 31-year-old man is referred to a neurologist due to his gradually increasing eccentric behavior and involuntary movements, especially the movements of his arms and hands. He also has difficulty with his short-term memory. Past medical history is otherwise noncontributory. His father had similar symptoms before he died but those symptoms started at the age of 33. His blood pressure is 125/92 mm Hg, pulse is 90/min, respiratory rate 12/min, and temperature is 36.6°C (97.9°F). Physical exam reveals involuntary writhing movements of hands, slow eye movements, and sporadic rigidity. The physician explains that this is an inherited disorder where the symptoms occur progressively at an earlier age than the parent and often with increased severity in the future generations. Which of the following is the most likely diagnosis of this patient?
Q1054
A 75-year-old woman with late-onset autoimmune diabetes mellitus, rheumatoid arthritis, coronary artery disease, and idiopathic pulmonary fibrosis presents to the ship medic with altered mental status. While on her current cruise to the Caribbean islands, she experienced nausea, vomiting, and diarrhea. She takes aspirin, simvastatin, low-dose prednisone, glargine, and aspart. She is allergic to amoxicillin and shellfish. She works as a greeter at a warehouse and smokes 5 packs/day. Her temperature is 100.5°F (38.1°C), blood pressure is 90/55 mmHg, pulse is 130/min, and respirations are 30/min. Her pupils are equal and reactive to light bilaterally. Her lungs are clear to auscultation bilaterally, but her breath has a fruity odor. She has an early systolic murmur best appreciated at the left upper sternal border. She has reproducible peri-umbilical tenderness. Which of the following will most likely be present in this patient?
Q1055
A 69-year-old man presents with granulomatosis with polyangiitis diagnosed about 8 months ago. He was treated appropriately and states that his symptoms are well controlled. He is presenting today for a general follow up visit. His temperature is 99.0°F (37.2°C), blood pressure is 184/104 mmHg, pulse is 88/min, respirations are 12/min, and oxygen saturation is 98% on room air. His physical examination is notable for the findings in Figures A and B. Which of the following would be found in this patient on serum laboratory studies?
Q1056
A 15-year-old boy is brought to the office by his mother with complaints of facial puffiness and smoky urine. The mother noticed puffiness on her son’s face a week ago, and it has been progressively worsening since then. She also states that her son had a sore throat 3 weeks ago. The patient does not have fever/chills, changes in urinary frequency, or abdominal discomfort. On physical examination, facial edema is noted. The vital signs include: blood pressure 145/85 mm Hg, pulse 96/min, temperature 36.7°C (98.1°F), and respiratory rate 20/min.
A complete blood count report shows:
Hemoglobin 10.1 g/dL
RBC 4.9 million cells/µL
Hematocrit 46%
Total leukocyte count 6,800 cells/µL
Neutrophils 70%
Lymphocytes 26%
Monocytes 3%
Eosinophil 1%
Basophils 0%
Platelets 210,000 cells/µL
ESR 18 mm (1st hour)
Urinalysis shows:
pH 6.4
Color dark brown
RBC plenty
WBC 3–4/HPF
Protein absent
Cast RBC and granular casts
Glucose absent
Crystal none
Ketone absent
Nitrite absent
Which of the following laboratory findings can be expected in this patient?
Q1057
A 37-year-old man presents to the emergency department for a persistent fever. The patient states he has felt unwell for the past week and has felt subjectively febrile. The patient has a past medical history of a suicide attempt and alcohol abuse. He is not currently taking any medications. The patient admits to using heroin and cocaine and drinking 5-8 alcoholic drinks per day. His temperature is 103°F (39.4°C), blood pressure is 92/59 mmHg, pulse is 110/min, respirations are 20/min, and oxygen saturation is 96% on room air. Cardiopulmonary exam is notable for a systolic murmur heard best along the left sternal border. Dermatologic exam reveals scarring in the antecubital fossa. Which of the following is the next best step in management?
Q1058
A 55-year-old male bodybuilder presents to the emergency department with weakness of his right arm. The patient states he has experienced these symptoms for a few weeks; however, today his hand felt so weak he dropped his cup of tea. The patient has a past medical history of diabetes. He drinks 2-7 alcoholic drinks per day and has smoked 2 packs of cigarettes per day since he was 25. The patient admits to using anabolic steroids. He has lost 17 pounds since he last came to the emergency department 1 month ago. His temperature is 99.5°F (37.5°C), blood pressure is 177/108 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam reveals decreased sensation in the right arm and 2/5 strength in the right arm and 5/5 strength in the left arm. The patient states that he is experiencing a dull aching and burning pain in his right arm during the exam. Which of the following is the most likely diagnosis?
Q1059
A 69-year-old woman comes to the physician because of a 3-week history of headache and worsening vision. Ophthalmologic examination shows a visual acuity of 20/120 in the right eye and 20/80 in the left eye. Physical examination shows no other abnormalities. Laboratory studies show a hemoglobin of 14.2 g/dL and total serum calcium of 9.9 mg/dL. A photomicrograph of a peripheral blood smear is shown. Serum electrophoresis shows increased concentration of a pentameric immunoglobulin. Which of the following is the most likely diagnosis?
Q1060
A 70-year-old man is accompanied by his wife to the primary care clinic for hand tremors. He states that he first noticed the tremor of his left hand 1 year ago. Since then, the tremor has been worsening and now he can hardly relax when trying to read. His wife says that she is also worried about his memory. She had to take over the finances several weeks ago after learning that he had forgotten to pay the bills for the past few months. The patient’s medical history is significant for hypertension. He takes aspirin and amlodipine. His mother had schizophrenia. The patient drinks 1-2 beers a night and is a former cigar smoker. On physical examination, he speaks softly and has reduced facial expressions. He has a resting tremor that is worse on the left, and he resists manipulation of his bilateral upper extremities. Which of the following is the most likely diagnosis?
Cardiology US Medical PG Practice Questions and MCQs
Question 1051: A 74-year-old gentleman presents to his family practitioner with the complaint of an inability to open his left eye since this morning. He also complains of intermittent pain and numbness in his left arm that has been present for the last few days. He denies ocular pain, difficulty swallowing, fatigability, or diplopia. His symptoms remain constant without fluctuation. He has a history of diabetes mellitus type 2, hypertension, and hypercholesterolemia. Further history reveals that he has lost 5.4 kg (12 lb) of weight in the past 4 months. He is a chronic smoker with a 72 pack-year smoking history. His blood pressure is 142/76 mm Hg, the heart rate is 76/min, the respiratory rate is 12/min, the temperature is 36.8°C (98.4°F), and BMI is the 18.2 kg/m2. The patient is awake, alert, and oriented to person, place, and time. He has partial drooping of the left eyelid while the right eyelid appears normal. The left pupil is 1 mm and the right pupil is 3 mm in diameter. Extraocular muscle movements are normal. What additional clinical feature would most likely be present in this patient?
A. Facial asymmetry
B. Urinary retention
C. Ipsilateral loss of touch sensations on the face
D. Tongue deviation to the left side
E. Loss of hemifacial sweating (Correct Answer)
Explanation: ***Loss of hemifacial sweating***
- The patient's presentation with **ptosis**, **miosis**, and an absence of other cranial nerve deficits strongly suggests **Horner's syndrome**. This syndrome is characterized by the classic triad of **ptosis**, **miosis**, and **anhidrosis** (loss of sweating).
- The history of **weight loss**, **smoking**, and intermittent left arm pain and numbness raises concern for a **Pancoast tumor** in the lung apex, which can compress the sympathetic chain and cause Horner's syndrome.
*Facial asymmetry*
- **Facial asymmetry** typically results from lesions affecting the facial nerve (cranial nerve VII), such as in Bell's palsy or stroke.
- While ptosis can cause some asymmetry in eye appearance, it does not typically lead to generalized facial asymmetry in the way a CN VII lesion would, as other facial muscles are unaffected.
*Urinary retention*
- **Urinary retention** is not a typical symptom of Horner's syndrome, which primarily affects the sympathetic innervation to the eye and face.
- It could be associated with conditions affecting the bladder's innervation, such as spinal cord lesions or prostate enlargement, which are not directly indicated here.
*Ipsilateral loss of touch sensations on the face*
- **Loss of touch sensations on the face** would indicate involvement of the trigeminal nerve (cranial nerve V) or its sensory pathways.
- Horner's syndrome specifically affects the sympathetic nervous system and does not directly cause sensory deficits on the face.
*Tongue deviation to the left side*
- **Tongue deviation** to one side is a sign of hypoglossal nerve (cranial nerve XII) palsy, which would affect the ipsilateral tongue muscles.
- This symptom is unrelated to Horner's syndrome, which involves oculosympathetic pathways.
Question 1052: A 68-year-old male is brought to the emergency department by his wife. An hour earlier, he dropped to the floor and began to violently shake his extremities. He urinated on the carpet and seemed confused for several minutes after. He is now feeling better. He has never experienced an episode like this before, nor does he think anyone in his family has. He and his wife are concerned that he has unintentionally lost 22.6 kg (50 lb) in the past 6 months. He has also been experiencing chest pain and has coughed up blood on a few occasions. He has a 50-pack-year smoking history and quit 2 years ago. His temperature is 36.8°C (98.2°F), heart rate is 98/min, respiratory rate is 15/min, blood pressure is 100/75 mm Hg, and his O2 saturation is 100% on room air. The physical exam, including a full neurologic and cardiac assessment, demonstrates no abnormal findings. Edema, ascites, and skin tenting are notably absent. A brain MRI does not indicate areas of infarction or metastatic lesions. ECG is normal. Urine toxicology screen is negative. EEG is pending. Laboratory findings are shown below:
BUN 15 mg/dL N: 7 to 20 mg/dL
pCO2 40 mm Hg N: 35-45 mm Hg
Creatinine 0.8 mg/dL N: 0.8 to 1.4 mg/dL
Glucose 95 mg/dL N: 64 to 128 mg/dL
Serum chloride 103 mmol/L N: 101 to 111 mmol/L
Serum potassium 3.9 mEq/L N: 3.7 to 5.2 mEq/L
Serum sodium 115 mEq/L N: 136 to 144 mEq/L
Total calcium 2.3 mmol/L N: 2-2.6 mmol/L
Magnesium 1.7 mEq/L N: 1.5-2 mEq/L
Phosphate 0.9 mmol/L N: 0.8-1.5 mmol/L
Hemoglobin 14 g/dL N: 13-17 g/dL (men), 12-15 g/dL (women)
Glycosylated hemoglobin 5.5% N: 4%-6%
Total cholesterol 4 mmol/L N: 3-5.5 mmol/L
Bicarbonate (HCO3) 19 mmol/L N: 18-22 mmol/L
What is indicated first?
A. Chemotherapy
B. Hypertonic saline (Correct Answer)
C. Diazepam
D. Phenytoin
E. Valproic acid
Explanation: ***Hypertonic saline***
- This patient presents with **severe symptomatic hyponatremia** (Na 115 mEq/L) evidenced by a generalized seizure and post-ictal confusion. Rapid correction with **hypertonic saline** is indicated to prevent cerebral edema and further neurological deterioration.
- Given the patient's significant weight loss, hemoptysis, and smoking history, an underlying malignancy (e.g., **small cell lung cancer** causing SIADH) is highly suspected, which can lead to chronic hyponatremia and acute symptomatic worsening.
*Chemotherapy*
- While an underlying malignancy, possibly **small cell lung cancer**, is strongly suggested by the patient's symptoms (weight loss, hemoptysis, smoking history) and likely cause of SIADH, chemotherapy is not the immediate priority for an acute seizure caused by severe hyponatremia.
- The patient's **acute neurological symptoms** and severely low sodium level require immediate stabilization before definitive cancer treatment.
*Diazepam*
- **Diazepam** is a benzodiazepine used to treat acute seizures. However, in this case, the seizure is a direct consequence of **severe hyponatremia**.
- While it could temporarily stop the seizure, it does not address the underlying **electrolyte imbalance**, which is the root cause and a life-threatening condition in itself.
*Phenytoin*
- **Phenytoin** is an antiepileptic drug used for seizure prophylaxis and treatment. However, it is not the primary treatment for seizures directly caused by **metabolic derangements** like severe hyponatremia.
- Correcting the underlying **sodium imbalance** is paramount, as antiepileptics alone will not prevent recurrence or address the cerebral edema associated with hyponatremia.
*Valproic acid*
- **Valproic acid** is an antiepileptic medication used for various seizure types. Similar to phenytoin, it is not the first-line treatment for seizures secondary to **acute symptomatic hyponatremia**.
- The immediate focus must be on normalizing the patient's **sodium levels** with hypertonic saline to resolve the seizure and prevent further neurological damage.
Question 1053: A 31-year-old man is referred to a neurologist due to his gradually increasing eccentric behavior and involuntary movements, especially the movements of his arms and hands. He also has difficulty with his short-term memory. Past medical history is otherwise noncontributory. His father had similar symptoms before he died but those symptoms started at the age of 33. His blood pressure is 125/92 mm Hg, pulse is 90/min, respiratory rate 12/min, and temperature is 36.6°C (97.9°F). Physical exam reveals involuntary writhing movements of hands, slow eye movements, and sporadic rigidity. The physician explains that this is an inherited disorder where the symptoms occur progressively at an earlier age than the parent and often with increased severity in the future generations. Which of the following is the most likely diagnosis of this patient?
A. Neurofibromatosis
B. Myotonic dystrophy
C. Wilson's disease
D. Huntington's disease (Correct Answer)
E. Friedreich ataxia
Explanation: ***Huntington's disease***
- The patient's **involuntary writhing movements (chorea)**, **eccentric behavior**, and **short-term memory difficulty** are classic symptoms of Huntington's disease.
- The family history of similar symptoms starting at an earlier age in the father, along with the physician's comment about progressive earlier onset and increasing severity in future generations, points to **anticipation**, a characteristic genetic feature of Huntington's disease due to expansion of **CAG trinucleotide repeats**.
*Neurofibromatosis*
- This is a group of genetic disorders that primarily cause **tumors to grow on nerve tissue**, leading to skin changes, bone deformities, and neurological symptoms, but not typically chorea or progressive behavioral changes with anticipation in this manner.
- Key features include **café-au-lait spots** and neurofibromas, which are not mentioned in the patient's presentation.
*Myotonic dystrophy*
- This is characterized by **muscle weakness and myotonia** (prolonged muscle contraction), along with cataracts, heart problems, and endocrine dysfunction.
- While it also exhibits anticipation, its primary neurological presentation is not chorea or psychiatric symptoms like those described.
*Wilson's disease*
- This is an **autosomal recessive disorder** of copper metabolism, leading to copper accumulation in the liver, brain, and other organs.
- It can cause neurological symptoms like **tremors**, **dysarthria**, and **dystonia**, and psychiatric symptoms, but **chorea is less common** and **Kayser-Fleischer rings** are a hallmark finding, which are not mentioned here.
*Friedreich ataxia*
- This is an **autosomal recessive neurodegenerative disorder** characterized by **progressive ataxia**, dysarthria, and loss of proprioception, usually beginning in childhood or adolescence.
- It does not involve chorea or the prominent psychiatric symptoms and anticipation pattern described in this patient.
Question 1054: A 75-year-old woman with late-onset autoimmune diabetes mellitus, rheumatoid arthritis, coronary artery disease, and idiopathic pulmonary fibrosis presents to the ship medic with altered mental status. While on her current cruise to the Caribbean islands, she experienced nausea, vomiting, and diarrhea. She takes aspirin, simvastatin, low-dose prednisone, glargine, and aspart. She is allergic to amoxicillin and shellfish. She works as a greeter at a warehouse and smokes 5 packs/day. Her temperature is 100.5°F (38.1°C), blood pressure is 90/55 mmHg, pulse is 130/min, and respirations are 30/min. Her pupils are equal and reactive to light bilaterally. Her lungs are clear to auscultation bilaterally, but her breath has a fruity odor. She has an early systolic murmur best appreciated at the left upper sternal border. She has reproducible peri-umbilical tenderness. Which of the following will most likely be present in this patient?
A. Respiratory alkalosis and anion-gap metabolic acidosis (Correct Answer)
B. Respiratory acidosis and anion-gap metabolic acidosis
C. Respiratory alkalosis and non anion-gap metabolic acidosis
D. Respiratory acidosis and contraction metabolic alkalosis
E. Respiratory alkalosis and non-contraction metabolic alkalosis
Explanation: ***Respiratory alkalosis and anion-gap metabolic acidosis***
- The patient's **fruity-smelling breath**, history of diabetes, and symptoms of nausea, vomiting, and diarrhea strongly suggest **diabetic ketoacidosis (DKA)**, which causes a **high anion-gap metabolic acidosis** from accumulation of ketoacids (beta-hydroxybutyrate and acetoacetate).
- The markedly increased respiratory rate (30/min) represents **Kussmaul breathing** - a compensatory hyperventilation mechanism attempting to blow off CO2 and normalize pH. While this is technically **respiratory compensation for metabolic acidosis** rather than a primary respiratory alkalosis, the arterial blood gas will show a **low PaCO2** (respiratory alkalosis pattern) alongside the **low pH and low HCO3** (metabolic acidosis).
- This represents a **partially compensated metabolic acidosis** with high anion gap, which is the classic acid-base disturbance in DKA.
*Respiratory acidosis and anion-gap metabolic acidosis*
- **Respiratory acidosis** would imply hypoventilation (decreased respiratory rate or impaired ventilation) with CO2 retention, which is contrary to the patient's markedly elevated respiratory rate (30/min). The patient is hyperventilating, not hypoventilating.
- While **anion-gap metabolic acidosis** is correct due to DKA, the respiratory component is incorrect.
*Respiratory alkalosis and non anion-gap metabolic acidosis*
- While the low PaCO2 from compensatory hyperventilation would be present, **non-anion-gap metabolic acidosis** is incorrect.
- **Non-anion-gap metabolic acidosis** is typically caused by conditions like diarrhea (GI HCO3 loss) or renal tubular acidosis, whereas DKA characteristically causes a **high anion-gap metabolic acidosis** due to accumulation of unmeasured anions (ketoacids).
*Respiratory acidosis and contraction metabolic alkalosis*
- This option incorrectly identifies both acid-base components. The patient is **hyperventilating** (not hypoventilating), ruling out respiratory acidosis.
- **Contraction alkalosis** occurs with severe volume depletion and diuretic use when chloride depletion leads to metabolic alkalosis, which does not fit the DKA presentation where ketoacid accumulation causes metabolic acidosis.
*Respiratory alkalosis and non-contraction metabolic alkalosis*
- While the compensatory hyperventilation results in low PaCO2, **metabolic alkalosis** (whether contraction or non-contraction) is inconsistent with DKA, which causes metabolic **acidosis**, not alkalosis.
- **Non-contraction metabolic alkalosis** is associated with conditions like hyperaldosteronism or vomiting with gastric acid loss, not with ketoacid accumulation.
Question 1055: A 69-year-old man presents with granulomatosis with polyangiitis diagnosed about 8 months ago. He was treated appropriately and states that his symptoms are well controlled. He is presenting today for a general follow up visit. His temperature is 99.0°F (37.2°C), blood pressure is 184/104 mmHg, pulse is 88/min, respirations are 12/min, and oxygen saturation is 98% on room air. His physical examination is notable for the findings in Figures A and B. Which of the following would be found in this patient on serum laboratory studies?
A. Hypokalemia and metabolic acidosis
B. Hyperkalemia and metabolic acidosis
C. Hypokalemia and normal acid-base status
D. Hyperkalemia and metabolic alkalosis
E. Hypokalemia and metabolic alkalosis (Correct Answer)
Explanation: ***Hypokalemia and metabolic alkalosis***
- The patient's **hypertension**, along with the appearance of **edema** (Figure A) and **facial plethora or moon facies** (Figure B), is highly suggestive of **Cushing's syndrome**, often caused by long-term corticosteroid use for granulomatosis with polyangiitis.
- Corticosteroid excess leads to **mineralocorticoid effects**, causing **sodium and water retention**, hypertension, and increased **potassium excretion**, resulting in **hypokalemia** and a compensatory **metabolic alkalosis**.
*Hypokalemia and metabolic acidosis*
- While corticosteroids can cause **hypokalemia**, they typically lead to **metabolic alkalosis** due to increased hydrogen ion excretion, not acidosis.
- **Metabolic acidosis** is inconsistent with the mineralocorticoid effects seen with Cushing's syndrome.
*Hyperkalemia and metabolic acidosis*
- **Hyperkalemia** and **metabolic acidosis** are characteristic of **adrenal insufficiency**, which is the opposite of Cushing's syndrome.
- These findings are contrary to the clinical picture of corticosteroid excess indicated by hypertension and fluid retention.
*Hypokalemia and normal acid-base status*
- While **hypokalemia** is expected, the compensatory mechanisms for excess mineralocorticoid activity typically alter acid-base balance, leading to **metabolic alkalosis**, not a normal status.
- A normal acid-base status would be atypical given the significant renal tubular effects of corticosteroid excess.
*Hyperkalemia and metabolic alkalosis*
- **Hyperkalemia** is inconsistent with corticosteroid excess, which promotes **potassium excretion**.
- Although **alkalosis** is possible, the combination with hyperkalemia does not fit the typical profile of Cushing's syndrome.
Question 1056: A 15-year-old boy is brought to the office by his mother with complaints of facial puffiness and smoky urine. The mother noticed puffiness on her son’s face a week ago, and it has been progressively worsening since then. She also states that her son had a sore throat 3 weeks ago. The patient does not have fever/chills, changes in urinary frequency, or abdominal discomfort. On physical examination, facial edema is noted. The vital signs include: blood pressure 145/85 mm Hg, pulse 96/min, temperature 36.7°C (98.1°F), and respiratory rate 20/min.
A complete blood count report shows:
Hemoglobin 10.1 g/dL
RBC 4.9 million cells/µL
Hematocrit 46%
Total leukocyte count 6,800 cells/µL
Neutrophils 70%
Lymphocytes 26%
Monocytes 3%
Eosinophil 1%
Basophils 0%
Platelets 210,000 cells/µL
ESR 18 mm (1st hour)
Urinalysis shows:
pH 6.4
Color dark brown
RBC plenty
WBC 3–4/HPF
Protein absent
Cast RBC and granular casts
Glucose absent
Crystal none
Ketone absent
Nitrite absent
Which of the following laboratory findings can be expected in this patient?
A. Increased C3 level
B. Positive streptozyme test (Correct Answer)
C. Normal erythrocyte sedimentation rate
D. Decreased serum creatinine
E. Negative antistreptolysin O (ASO) titer
Explanation: ***Positive streptozyme test***
- The clinical presentation of **facial puffiness**, **smoky urine**, and a history of a **sore throat 3 weeks prior** are highly suggestive of **post-streptococcal glomerulonephritis (PSGN)**.
- A **streptozyme test** detects antibodies to several streptococcal antigens (streptolysin O, hyaluronidase, streptokinase, DNase B, and NADase), making it a comprehensive and sensitive indicator of recent streptococcal infection.
*Increased C3 level*
- In **PSGN**, activation of the complement system by immune complexes typically leads to a **reduction in C3 levels**, not an increase.
- While C3 levels usually return to normal within 6-8 weeks, acutely they would be depressed.
*Normal erythrocyte sedimentation rate*
- The given ESR of **18 mm** is slightly elevated for a healthy child (normal range typically <15 mm/hr for this age group), indicating an ongoing inflammatory process.
- In conditions like PSGN, inflammation of the glomeruli would likely cause an **elevated ESR**.
*Decreased serum creatinine*
- The patient's blood pressure of **145/85 mm Hg** and the active urinary findings (RBC casts, granular casts) point towards **acute kidney injury** or **renal impairment**.
- This would lead to an **increased serum creatinine**, reflecting reduced glomerular filtration, rather than a decrease.
*Negative antistreptolysin O (ASO) titer*
- A **recent streptococcal infection** is the precursor to PSGN, and an **elevated ASO titer** is one of the key laboratory findings supporting this diagnosis.
- A negative ASO titer would argue against the diagnosis of PSGN, although other streptococcal antibodies (detected by a streptozyme test) can still be positive.
Question 1057: A 37-year-old man presents to the emergency department for a persistent fever. The patient states he has felt unwell for the past week and has felt subjectively febrile. The patient has a past medical history of a suicide attempt and alcohol abuse. He is not currently taking any medications. The patient admits to using heroin and cocaine and drinking 5-8 alcoholic drinks per day. His temperature is 103°F (39.4°C), blood pressure is 92/59 mmHg, pulse is 110/min, respirations are 20/min, and oxygen saturation is 96% on room air. Cardiopulmonary exam is notable for a systolic murmur heard best along the left sternal border. Dermatologic exam reveals scarring in the antecubital fossa. Which of the following is the next best step in management?
A. CT scan
B. Ultrasound
C. Chest radiograph
D. Blood cultures (Correct Answer)
E. Vancomycin and gentamicin
Explanation: ***Blood cultures***
- The patient's history of **intravenous drug use (IVDU)**, persistent fever, and a **new systolic murmur** strongly suggest **infective endocarditis**.
- **Blood cultures** are crucial for identifying the causative organism and guiding appropriate antibiotic therapy, serving as the cornerstone of diagnosis in suspected endocarditis.
*CT scan*
- While CT scans can be useful for identifying complications of endocarditis (e.g., septic emboli in the brain or lungs), they are **not the initial diagnostic step** for identifying the source of infection.
- CT scans expose the patient to **radiation** and are more expensive, making them less suitable as a first step compared to blood cultures.
*Ultrasound*
- An **echocardiogram** (a type of ultrasound) is essential for visualizing vegetations on heart valves, but it is typically performed *after* blood cultures reveal bacteremia to confirm the diagnosis and assess severity.
- A general ultrasound of other body areas would be non-specific and **unlikely to pinpoint the cause** of persistent fever in this clinical context.
*Chest radiograph*
- A chest radiograph can identify **pulmonary infiltrates** or **septic emboli in the lungs**, which are potential complications of right-sided endocarditis (common in IVDU).
- However, a chest radiograph **does not identify the causative organism** or confirm the primary diagnosis of endocarditis, making it a secondary investigation.
*Vancomycin and gentamicin*
- This combination represents a broad-spectrum antibiotic regimen often used for **empiric treatment of infective endocarditis**, particularly in IVDU patients due to concerns for MRSA or resistant streptococcal species.
- While ultimately necessary, administering antibiotics *before* obtaining **blood cultures** can significantly reduce the yield of cultures and hinder definitive diagnosis and tailored treatment.
Question 1058: A 55-year-old male bodybuilder presents to the emergency department with weakness of his right arm. The patient states he has experienced these symptoms for a few weeks; however, today his hand felt so weak he dropped his cup of tea. The patient has a past medical history of diabetes. He drinks 2-7 alcoholic drinks per day and has smoked 2 packs of cigarettes per day since he was 25. The patient admits to using anabolic steroids. He has lost 17 pounds since he last came to the emergency department 1 month ago. His temperature is 99.5°F (37.5°C), blood pressure is 177/108 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam reveals decreased sensation in the right arm and 2/5 strength in the right arm and 5/5 strength in the left arm. The patient states that he is experiencing a dull aching and burning pain in his right arm during the exam. Which of the following is the most likely diagnosis?
A. Brachial plexopathy
B. Apical lung tumor (Correct Answer)
C. Subclavian steal syndrome
D. Cerebral infarction
E. Scalenus anticus syndrome
Explanation: ***Apical lung tumor***
- The patient's history of **heavy smoking** and **anabolic steroid use**, along with **unexplained weight loss**, **weakness**, and **sensory deficits in the arm**, are highly suggestive of an apical lung tumor (Pancoast tumor) compressing the brachial plexus.
- The **dull aching and burning pain** in the arm is a classic symptom of brachial plexus involvement caused by tumor invasion.
*Brachial plexopathy*
- While brachial plexopathy explains the **arm weakness and sensory changes**, it is a general term and doesn't identify the underlying cause.
- The patient's risk factors (smoking, weight loss) point to a more specific etiology than just idiopathic plexopathy.
*Subclavian steal syndrome*
- This condition involves **vertebrobasilar insufficiency** due to subclavian artery stenosis, typically presenting with neurologic symptoms like vertigo, syncope, and arm claudication, especially during arm exercise.
- It does not typically cause **unilateral arm weakness and sensory deficits** associated with unexplained weight loss.
*Cerebral infarction*
- A cerebral infarction (stroke) would cause **sudden-onset neurological deficits**, which is inconsistent with the patient's several weeks of symptoms progressing to severe weakness.
- While it can cause hemiparesis, the presentation of **dull aching and burning pain** in the arm suggests peripheral nerve involvement rather than a central lesion.
*Scalenus anticus syndrome*
- Also known as **thoracic outlet syndrome**, this typically involves compression of the brachial plexus or subclavian vessels, often due to anatomical variations or trauma.
- While it can cause arm pain and weakness, the patient's significant **smoking history** and **unexplained weight loss** strongly point to a more serious underlying malignancy.
Question 1059: A 69-year-old woman comes to the physician because of a 3-week history of headache and worsening vision. Ophthalmologic examination shows a visual acuity of 20/120 in the right eye and 20/80 in the left eye. Physical examination shows no other abnormalities. Laboratory studies show a hemoglobin of 14.2 g/dL and total serum calcium of 9.9 mg/dL. A photomicrograph of a peripheral blood smear is shown. Serum electrophoresis shows increased concentration of a pentameric immunoglobulin. Which of the following is the most likely diagnosis?
A. Multiple myeloma
B. Hyper IgM syndrome
C. Waldenstrom macroglobulinemia (Correct Answer)
D. Essential thrombocythemia
E. Giant cell arteritis
Explanation: ***Waldenstrom macroglobulinemia***
- This condition is characterized by the overproduction of **monoclonal IgM** (a pentameric immunoglobulin), which can lead to **hyperviscosity syndrome**.
- Symptoms like **headache** and **worsening vision** in an elderly patient, combined with increased IgM, are classic presentations of hyperviscosity associated with Waldenstrom macroglobulinemia.
*Multiple myeloma*
- This plasma cell disorder typically involves the overproduction of **IgG or IgA**, not IgM.
- While it can cause headaches and vision problems, it's often accompanied by **bone pain**, **hypercalcemia**, **renal failure**, and recurrent infections, which are not described here.
*Hyper IgM syndrome*
- This is a rare **primary immunodeficiency** characterized by normal or increased IgM levels but decreased levels of IgG, IgA, and IgE, leading to recurrent infections.
- It usually presents in childhood and is not associated with the **hyperviscosity symptoms** seen in this patient.
*Essential thrombocythemia*
- This is a **myeloproliferative neoplasm** characterized by an elevated platelet count, which increases the risk of thrombosis or hemorrhage.
- It does not involve immunoglobulin overproduction or present with symptoms indicative of **hyperviscosity syndrome**.
*Giant cell arteritis*
- This condition is an **inflammatory vasculitis** that can cause headache and vision loss, similar to the patient's symptoms.
- However, it is typically associated with an **elevated erythrocyte sedimentation rate (ESR)** and C-reactive protein, and would not show increased pentameric immunoglobulin on serum electrophoresis.
Question 1060: A 70-year-old man is accompanied by his wife to the primary care clinic for hand tremors. He states that he first noticed the tremor of his left hand 1 year ago. Since then, the tremor has been worsening and now he can hardly relax when trying to read. His wife says that she is also worried about his memory. She had to take over the finances several weeks ago after learning that he had forgotten to pay the bills for the past few months. The patient’s medical history is significant for hypertension. He takes aspirin and amlodipine. His mother had schizophrenia. The patient drinks 1-2 beers a night and is a former cigar smoker. On physical examination, he speaks softly and has reduced facial expressions. He has a resting tremor that is worse on the left, and he resists manipulation of his bilateral upper extremities. Which of the following is the most likely diagnosis?
A. Dementia with Lewy bodies
B. Parkinson disease (Correct Answer)
C. Essential tremor
D. Progressive supranuclear palsy
E. Tardive dyskinesia
Explanation: ***Parkinson disease***
- The patient exhibits classic symptoms of **Parkinson disease**, including a **unilateral resting tremor** (left hand), **bradykinesia** (soft speech, reduced facial expressions), and **rigidity** (resists manipulation of upper extremities).
- The associated **cognitive decline** (memory issues, forgetting to pay bills) is also common in Parkinson disease, developing often after the motor symptoms.
*Dementia with Lewy bodies*
- While **cognitive fluctuations**, **visual hallucinations**, and **Parkinsonism** can occur in Dementia with Lewy bodies, the **dementia** typically precedes or coincides with the motor symptoms, unlike the progression seen here where motor symptoms appeared first.
- Distinctive features like **recurrent visual hallucinations** and **fluctuating cognition** are not explicitly mentioned as prominent in this case.
*Essential tremor*
- **Essential tremor** is typically an **action tremor** that worsens with movement and improves at rest, whereas this patient has a **resting tremor**.
- It usually affects both sides of the body symmetrically and is not typically associated with **bradykinesia**, **rigidity**, or **cognitive decline**.
*Progressive supranuclear palsy*
- **Progressive supranuclear palsy** is characterized by **early postural instability** and falls, **supranuclear ophthalmoplegia** (especially vertical gaze palsy), and a more **symmetric Parkinsonism** that is often resistant to levodopa.
- The predominant **asymmetric resting tremor** and **cogwheel rigidity** observed in this patient are less typical of this condition.
*Tardive dyskinesia*
- **Tardive dyskinesia** is a unique movement disorder characterized by **involuntary, repetitive, and purposeless movements**, usually of the face (e.g., grimacing, tongue protrusion, lip smacking) and limbs.
- It results from **chronic dopamine receptor blockade** typically due to antipsychotic medications, which the patient is not taking, and presents differently from the patient's symptoms.
