A 72-year-old man presents to the ED complaining of worsening abdominal pain over the last few hours. He also reports nausea, but denies fever, vomiting, or changes in the appearance of his bowel movements. His medical history is significant for type 2 diabetes mellitus, hypertension, coronary artery disease, stroke, atrial fibrillation, and peptic ulcer disease. Due to his recurrent bleeding peptic ulcers, he does not take warfarin. His surgical history is significant for an appendectomy as a child. His medications include metformin, lisinopril, metoprolol, and omeprazole. He has a 50-pack-year history of smoking. His temperature is 37.6 C (99.7 F), blood pressure is 146/80 mm Hg, pulse is 115/min, and respiratory rate is 20/min. On physical exam, he is in acute distress due to the pain. Pulmonary auscultation reveals scattered wheezes and decreased air entry. His heart rate is irregularly irregular, with no murmurs, rubs or gallops. Abdominal exam is significant for decreased bowel sounds and diffuse tenderness. Initial laboratory evaluation is as follows:
Na 138 mEq/L, Cl 101 mEq/L, HCO3 12 mEq/L, BUN 21 mg/dL, Cr 0.9 mg/dL, glucose 190 mg/dL, amylase 240 U/L (normal < 65 U/L).
What is the most likely diagnosis in this patient?
Q372
A 23-year-old college senior visits the university health clinic after vomiting large amounts of blood. He has been vomiting for the past 36 hours after celebrating his team’s win at the national hockey championship with his varsity friends while consuming copious amounts of alcohol. His personal medical history is unremarkable. His blood pressure is 129/89 mm Hg while supine and 100/70 mm Hg while standing. His pulse is 98/min, strong and regular, with an oxygen saturation of 98%. His body temperature is 36.5°C (97.7°F), while the rest of the physical exam is normal. Which of the following is associated with this patient’s condition?
Q373
A 48-year-old Caucasian woman presents to her physician for an initial visit. She has no chronic diseases. The past medical history is significant for myomectomy performed 10 years ago for a large uterine fibroid. She had 2 uncomplicated pregnancies and 2 spontaneous vaginal deliveries. Currently, she only takes oral contraceptives. She is a former smoker with a 3-pack-year history. Her last Pap test performed 2 years ago was negative. She had a normal blood glucose measurement 3 years ago. The family history is remarkable for systolic hypertension in her mother and older brother. The blood pressure is 110/80 mm Hg, heart rate is 76/min, respirations are 16/min, and oxygen saturation is 99% on room air. The patient is afebrile. The BMI is 32 kg/m2. Her physical examination is unremarkable. Which of the following preventative tests is indicated for this patient at this time?
Q374
A 35-year-old man presents with acute-onset right flank pain. He says that his symptoms began suddenly 6 hours ago and have not improved. He describes the pain as severe, colicky, and ‘coming in waves’. It is localized to the right flank and radiates to the groin. He says he has associated nausea. He denies any fever, chills, dysuria, or hematuria. His past medical history is significant for asymptomatic nephrolithiasis, diagnosed 9 months ago on an upright abdominal radiograph, which has not yet been treated. The patient’s vital signs include: temperature 37.0°C (98.6°F), blood pressure 145/90 mm Hg, pulse 119/min, and respiratory rate 21/min. On physical examination, the patient is constantly moving and writhing with pain. There is severe right costovertebral angle tenderness. The remainder of the physical examination is unremarkable. A urine dipstick shows 2+ blood. A noncontrast CT of the abdomen and pelvis reveals a 4-mm-diameter radiopaque stone at the right ureteropelvic junction. Several nonobstructing small-diameter stones are noted in the left kidney. Mild hydronephrosis of the right kidney is noted. Intravenous fluids are started and ondansetron is administered. Which of the following is the next best step in the management of this patient?
Q375
A 44-year-old woman comes to the physician because of a 2-year history of progressive dysphagia. She initially had symptoms only when consuming solid foods, but for the past 2 months she has also had difficulty swallowing liquids. She describes a feeling of food “getting stuck” in her throat. She was diagnosed with gastroesophageal reflux disease 2 years ago and has had episodic pallor of her fingers since adolescence. She has smoked half a pack of cigarettes daily for 24 years. Her only medication is omeprazole. Her pulse is 65/min, respirations are 12/min, and blood pressure is 127/73 mm Hg. Examination shows thickening of the skin of her fingers, with small white papules on her fingertips. There are small dilated blood vessels on her face, lips, and tongue. Cardiopulmonary examination shows no abnormalities. Which of the following is the most likely cause of this patient's dysphagia?
Q376
A previously healthy 30-year-old woman comes to the physician because of a 6-month history of a recurring rash that typically occurs on exposure to the sun and affects only the face. She also has noticed several nonpainful ulcers on the roof of her mouth. She is sexually active with one male partner and they use condoms inconsistently. Her mother has end-stage renal disease. The patient does not smoke or drink alcohol. Her vital signs are within normal limits. Physical examination shows an erythematous rash across the cheeks that spares the nasolabial folds. There are three small ulcers on the hard palate. Laboratory studies show:
Leukocyte count 3,000/mm3
Platelet count 70,000/mm3
Erythrocyte sedimentation rate 80 mm/h
Serum
Antinuclear antibodies 1:320
Anti-Smith antibodies positive
Urine
Protein 3+
RBC casts negative
RBCs none
WBCs 10–15/hpf
Which of the following is the most appropriate next step in management?
Q377
A 56-year-old woman presents to the emergency department with muscle weakness. She reports her symptoms have progressively worsened over the course of 2 weeks and are most significant in her lower extremities. She also notices increased urinary frequency. Approximately 1 month ago she was diagnosed with a calcium phosphate nephrolithiasis. Medical history is significant for rheumatoid arthritis diagnosed approximately 10 years ago treated with methotrexate, and type II diabetes mellitus treated with metformin. Her temperature is 98.6°F (37°C), blood pressure is 138/92 mmHg, pulse is 92/min, and respirations are 17/min. On physical exam, there is mild tenderness to palpation of the metacarpophalangeal and proximal interphalangeal joints. There is 4/5 power throughout the lower extremity. Laboratory testing is shown.
Serum:
Na+: 137 mEq/L
Cl-: 106 mEq/L
K+: 2.9 mEq/L
HCO3-: 18 mEq/L
Glucose: 115 mg/dL
Creatinine: 1.0 mg/dL
Urine pH: 5.6
Which of the following is the best next step in management?
Q378
A 23-year-old man complains of lower back pain that began approximately 6 months ago. He is unsure why he is experiencing this pain and notices that this pain is worse in the morning after waking up and improves with physical activity. Ibuprofen provides significant relief. He denies bowel and bladder incontinence or erectile dysfunction. Physical exam is notable for decreased chest expansion, decreased spinal range of motion, 5/5 strength in both lower extremities, 2+ patellar reflexes bilaterally, and an absence of saddle anesthesia. Which of the following is the most appropriate next test for this patient?
Q379
A 46-year-old woman presents to the emergency department complaining of abdominal pain, nausea, and vomiting approximately 4 hours after a fatty meal. She reports that this has happened before, but this episode is worse. The vomit was non-bilious and did not contain any blood. She recalls frequent episodes of vague epigastric pain that often wakes her up during the night. Over the counter omeprazole and a small meal or snack would provide some relief in the past. The patient also mentions recent anorexia and early satiety. She takes over the counter ibuprofen several times a week for headaches. Blood pressure is 125/82 mm Hg, pulse is 102/min, and respiratory rate is 19/min. On physical examination, she has hypoactive bowel sounds, and her abdomen seems grossly distended and tympanic on percussion. Which of the following is most consistent with a duodenal ulcer?
Q380
A 32-year-old man comes into your office because of pain in his right knee, left elbow, and left wrist. It started about a week ago but has particularly localized to his wrist. The patient states that he has 2 sexual partners. He states he has also had some white discharge from his penis with pruritis and pain during urination. His temperature is 97.6°F (36.4°C), blood pressure is 124/84 mmHg, pulse is 80/min, respirations are 12/min, and oxygen saturation is 98% on room air. Physical exam reveals pain upon palpation of the patient's left wrist which also appears erythematous and swollen. What is the best next step in management for this patient?
Gastroenterology US Medical PG Practice Questions and MCQs
Question 371: A 72-year-old man presents to the ED complaining of worsening abdominal pain over the last few hours. He also reports nausea, but denies fever, vomiting, or changes in the appearance of his bowel movements. His medical history is significant for type 2 diabetes mellitus, hypertension, coronary artery disease, stroke, atrial fibrillation, and peptic ulcer disease. Due to his recurrent bleeding peptic ulcers, he does not take warfarin. His surgical history is significant for an appendectomy as a child. His medications include metformin, lisinopril, metoprolol, and omeprazole. He has a 50-pack-year history of smoking. His temperature is 37.6 C (99.7 F), blood pressure is 146/80 mm Hg, pulse is 115/min, and respiratory rate is 20/min. On physical exam, he is in acute distress due to the pain. Pulmonary auscultation reveals scattered wheezes and decreased air entry. His heart rate is irregularly irregular, with no murmurs, rubs or gallops. Abdominal exam is significant for decreased bowel sounds and diffuse tenderness. Initial laboratory evaluation is as follows:
Na 138 mEq/L, Cl 101 mEq/L, HCO3 12 mEq/L, BUN 21 mg/dL, Cr 0.9 mg/dL, glucose 190 mg/dL, amylase 240 U/L (normal < 65 U/L).
What is the most likely diagnosis in this patient?
A. Acute cholecystitis
B. Peptic ulcer perforation
C. Acute mesenteric ischemia (Correct Answer)
D. Diabetic ketoacidosis
E. Acute pancreatitis
Explanation: ***Acute mesenteric ischemia***
- The patient has multiple risk factors for **mesenteric ischemia**, including **atrial fibrillation** (predisposing to emboli), **coronary artery disease, stroke**, and **smoking history**. Critically, he is **not anticoagulated** despite AF due to bleeding ulcers, significantly increasing embolic risk.
- The **acute onset of severe abdominal pain out of proportion to physical exam findings** (diffuse tenderness, decreased bowel sounds) in a patient with these risk factors is highly suggestive of mesenteric ischemia.
- The **lactic acidosis** (indicated by HCO3 of 12 mEq/L) and elevated pulse rate are consistent with **ischemic bowel**, as tissue hypoxia leads to anaerobic metabolism and lactate production.
- **Elevated amylase can occur in mesenteric ischemia** due to bowel wall hypoxia and increased intestinal permeability.
*Acute cholecystitis*
- Characterized by **right upper quadrant pain**, **Murphy's sign**, **fever**, and often **vomiting**, which are not present in this patient.
- The diffuse abdominal tenderness and strong vascular risk factors point away from this diagnosis.
*Peptic ulcer perforation*
- Typically presents with **sudden onset, severe, diffuse abdominal pain** with a **rigid, board-like abdomen** (peritonitis signs) and often **free air on imaging**.
- While the patient has a history of peptic ulcer disease, the absence of peritoneal signs like rigidity and the presence of significant vascular disease with lactic acidosis make mesenteric ischemia more likely.
*Diabetic ketoacidosis*
- Characterized by **hyperglycemia**, **anion gap metabolic acidosis**, **ketonemia/ketonuria**, and often **vomiting** and **altered mental status**.
- Although there is hyperglycemia (190 mg/dL) and metabolic acidosis, this glucose level is not high enough for DKA (typically >250 mg/dL), and the absence of vomiting, mental status changes, and ketonuria make this unlikely.
- The severity of acidosis (HCO3 12) with only modest hyperglycemia suggests **lactic acidosis** from tissue ischemia rather than DKA.
*Acute pancreatitis*
- Typically presents with **epigastric pain radiating to the back**, often associated with **nausea and vomiting**.
- While the amylase is elevated at 3.7 times the upper limit of normal (which meets diagnostic criteria), **amylase elevation can also occur in mesenteric ischemia** due to intestinal hypoxia and increased permeability.
- The **clinical context strongly favors ischemia**: multiple vascular risk factors, pain out of proportion to exam, severe lactic acidosis, and lack of typical pancreatitis features (epigastric/back pain pattern).
- The profound metabolic acidosis (HCO3 12) is more severe than typically seen in uncomplicated pancreatitis and suggests tissue ischemia.
Question 372: A 23-year-old college senior visits the university health clinic after vomiting large amounts of blood. He has been vomiting for the past 36 hours after celebrating his team’s win at the national hockey championship with his varsity friends while consuming copious amounts of alcohol. His personal medical history is unremarkable. His blood pressure is 129/89 mm Hg while supine and 100/70 mm Hg while standing. His pulse is 98/min, strong and regular, with an oxygen saturation of 98%. His body temperature is 36.5°C (97.7°F), while the rest of the physical exam is normal. Which of the following is associated with this patient’s condition?
A. Esophageal tear (Correct Answer)
B. Portal hypertension
C. Esophageal metaplasia
D. Esophageal varices
E. Esophageal perforation
Explanation: ***Esophageal tear***
- This patient's presentation of **hematemesis** after prolonged, forceful vomiting, especially following substantial alcohol consumption, is highly characteristic of a **Mallory-Weiss tear**.
- A Mallory-Weiss tear is a **longitudinal mucosal laceration** at the gastroesophageal junction, caused by the sudden increase in **intra-abdominal and intra-gastric pressure** during retching or vomiting.
*Portal hypertension*
- While portal hypertension can lead to upper GI bleeding from **esophageal varices**, there is no clinical evidence of **chronic liver disease** (e.g., jaundice, ascites, spider angiomata) in this otherwise healthy young man.
- The patient's unremarkable medical history and acute onset of symptoms after an episode of severe vomiting are not typical for a new presentation of chronic **portal hypertension**.
*Esophageal metaplasia*
- **Esophageal metaplasia (Barrett's esophagus)** is a change in the lining of the esophagus from squamous to columnar epithelium, usually due to chronic gastroesophageal reflux disease (GERD).
- It is an asymptomatic precursor to adenocarcinoma and does not cause acute, massive hematemesis without associated ulceration or malignancy.
*Esophageal varices*
- **Esophageal varices** are dilated veins in the lower esophagus that can rupture and cause life-threatening bleeding, typically due to **portal hypertension** from cirrhosis or other liver diseases.
- The patient's lack of a history of liver disease and the context of excessive vomiting make variceal bleeding less likely than a Mallory-Weiss tear.
*Esophageal perforation*
- **Esophageal perforation (Boerhaave syndrome)** is a transmural tear of the esophagus, also associated with severe vomiting, but it presents with more severe symptoms.
- Key differentiating features include **severe retrosternal chest pain**, **dyspnea**, **subcutaneous emphysema**, and potentially **septic shock** due to mediastinitis, none of which are described in this patient.
Question 373: A 48-year-old Caucasian woman presents to her physician for an initial visit. She has no chronic diseases. The past medical history is significant for myomectomy performed 10 years ago for a large uterine fibroid. She had 2 uncomplicated pregnancies and 2 spontaneous vaginal deliveries. Currently, she only takes oral contraceptives. She is a former smoker with a 3-pack-year history. Her last Pap test performed 2 years ago was negative. She had a normal blood glucose measurement 3 years ago. The family history is remarkable for systolic hypertension in her mother and older brother. The blood pressure is 110/80 mm Hg, heart rate is 76/min, respirations are 16/min, and oxygen saturation is 99% on room air. The patient is afebrile. The BMI is 32 kg/m2. Her physical examination is unremarkable. Which of the following preventative tests is indicated for this patient at this time?
A. Abdominal ultrasound
B. Colonoscopy
C. Pap smear
D. Chest CT
E. Fasting blood glucose (Correct Answer)
Explanation: ***Fasting blood glucose***
- This patient has a **BMI of 32 kg/m² (obesity)** and is 48 years old, which are significant risk factors for **type 2 diabetes mellitus**.
- The American Diabetes Association (ADA) recommends screening for type 2 diabetes with a **fasting plasma glucose**, 2-hour 75-g oral glucose tolerance test, or HbA1c in asymptomatic adults who are overweight or obese (BMI ≥25 kg/m² or ≥23 kg/m² in Asian Americans) and have one or more additional risk factors, or starting at age 35 for all individuals.
- Her **last glucose measurement was 3 years ago**, making rescreening appropriate at this visit.
- Given her obesity and the time interval, **diabetes screening is the highest priority preventative test** at this time.
*Abdominal ultrasound*
- An abdominal ultrasound is generally not indicated as a routine screening test in an asymptomatic 48-year-old woman without specific risk factors for abdominal pathology.
- While it's used to diagnose conditions like **gallstones** or **hepatic steatosis**, it is not a recommended preventative screening measure in this context.
*Colonoscopy*
- Routine screening colonoscopy is recommended starting at **age 45** for individuals of average risk.
- While this patient is 48 and colonoscopy screening would be appropriate if not previously done, the question provides no information about prior colonoscopy screening.
- More importantly, given her **obesity and 3-year interval since last glucose check**, diabetes screening takes priority as the most indicated test "at this time."
*Pap smear*
- The patient had a normal Pap test 2 years ago, and recommended screening intervals are typically every **3 years for cytology alone** or every 5 years for co-testing (cytology plus HPV) in women aged 30-65.
- Thus, a Pap smear is not indicated for another year based on current guidelines.
*Chest CT*
- Chest CT for lung cancer screening is indicated only for individuals with a significant **smoking history (≥20 pack-years)** and who are current smokers or have quit within the last 15 years, aged 50-80.
- This patient has a 3-pack-year history and is a former smoker, placing her well below the threshold for lung cancer screening with chest CT.
Question 374: A 35-year-old man presents with acute-onset right flank pain. He says that his symptoms began suddenly 6 hours ago and have not improved. He describes the pain as severe, colicky, and ‘coming in waves’. It is localized to the right flank and radiates to the groin. He says he has associated nausea. He denies any fever, chills, dysuria, or hematuria. His past medical history is significant for asymptomatic nephrolithiasis, diagnosed 9 months ago on an upright abdominal radiograph, which has not yet been treated. The patient’s vital signs include: temperature 37.0°C (98.6°F), blood pressure 145/90 mm Hg, pulse 119/min, and respiratory rate 21/min. On physical examination, the patient is constantly moving and writhing with pain. There is severe right costovertebral angle tenderness. The remainder of the physical examination is unremarkable. A urine dipstick shows 2+ blood. A noncontrast CT of the abdomen and pelvis reveals a 4-mm-diameter radiopaque stone at the right ureteropelvic junction. Several nonobstructing small-diameter stones are noted in the left kidney. Mild hydronephrosis of the right kidney is noted. Intravenous fluids are started and ondansetron is administered. Which of the following is the next best step in the management of this patient?
A. Potassium citrate
B. 24-hour urine chemistry
C. Emergency percutaneous nephrostomy
D. Hydrocodone and indomethacin (Correct Answer)
E. Lithotripsy
Explanation: ***Hydrocodone and indomethacin***
- The patient presents with **acute renal colic** due to a 4-mm obstructing ureteral stone, indicated by severe, colicky flank pain radiating to the groin, hematuria, and mild hydronephrosis on CT.
- The primary management goal is **adequate pain control** while allowing time for spontaneous stone passage (stones <5 mm have ~80% spontaneous passage rate).
- **Indomethacin (NSAID)** is first-line therapy for renal colic, providing analgesia by reducing prostaglandin-mediated inflammation and decreasing ureteral spasm.
- **Hydrocodone (opioid analgesic)** is added for additional pain relief given the severity of symptoms (patient writhing in pain, tachycardic), as monotherapy may be insufficient for severe renal colic.
- The combination provides multimodal analgesia for optimal pain control in this acute setting.
*Potassium citrate*
- **Potassium citrate** alkalinizes urine and is used for **prevention of recurrent stones** (particularly calcium oxalate and uric acid stones).
- This is a long-term preventive measure, not indicated for acute pain management of an obstructing stone.
*24-hour urine chemistry*
- **24-hour urine collection** evaluates metabolic abnormalities contributing to stone formation (calcium, oxalate, citrate, uric acid levels).
- This is appropriate for **recurrence prevention workup** after the acute episode resolves, not for immediate management of acute renal colic.
*Emergency percutaneous nephrostomy*
- **Percutaneous nephrostomy** is indicated for: obstructive uropathy with **concomitant infection (obstructive pyelonephritis)**, **solitary kidney with obstruction**, **bilateral obstruction**, **acute kidney injury**, or **refractory pain** despite maximal medical therapy.
- This patient has no fever/signs of infection, no evidence of acute kidney injury, and has not yet received adequate analgesic trial; thus, emergency decompression is not indicated.
*Lithotripsy*
- **Extracorporeal shock wave lithotripsy (ESWL)** or ureteroscopy are options for stones unlikely to pass spontaneously.
- A **4-mm stone at the ureteropelvic junction** has a high probability of spontaneous passage with conservative management (hydration, analgesia, medical expulsive therapy).
- Intervention is typically reserved for: stones >10 mm, persistent obstruction >4-6 weeks, intractable pain, or progressive kidney injury.
Question 375: A 44-year-old woman comes to the physician because of a 2-year history of progressive dysphagia. She initially had symptoms only when consuming solid foods, but for the past 2 months she has also had difficulty swallowing liquids. She describes a feeling of food “getting stuck” in her throat. She was diagnosed with gastroesophageal reflux disease 2 years ago and has had episodic pallor of her fingers since adolescence. She has smoked half a pack of cigarettes daily for 24 years. Her only medication is omeprazole. Her pulse is 65/min, respirations are 12/min, and blood pressure is 127/73 mm Hg. Examination shows thickening of the skin of her fingers, with small white papules on her fingertips. There are small dilated blood vessels on her face, lips, and tongue. Cardiopulmonary examination shows no abnormalities. Which of the following is the most likely cause of this patient's dysphagia?
A. Degeneration of upper and lower motor neurons
B. Esophageal smooth muscle atrophy and fibrosis (Correct Answer)
C. Uncoordinated contractions of the esophagus
D. Outpouching of the lower pharyngeal mucosa and submucosa
E. Protrusion of thin tissue membranes into the esophagus
Explanation: ***Esophageal smooth muscle atrophy and fibrosis***
- The constellation of **progressive dysphagia** (both solids and liquids), **Raynaud's phenomenon** (episodic pallor of fingers since adolescence), **skin thickening of fingers**, **small white papules on fingertips** (calcinosis), and **telangiectasias** (dilated blood vessels on face, lips, tongue) strongly points to **systemic sclerosis (scleroderma)**, specifically its limited form (CREST syndrome).
- In systemic sclerosis, **smooth muscle atrophy and fibrosis** in the esophagus lead to impaired peristalsis and esophageal sphincter dysfunction, causing the dysphagia.
*Degeneration of upper and lower motor neurons*
- This describes **amyotrophic lateral sclerosis (ALS)**, which can present with dysphagia due to bulbar involvement. However, ALS does not explain the cutaneous manifestations, Raynaud's phenomenon, or telangiectasias seen in this patient.
- The dysphagia in ALS is typically due to **neuromuscular weakness** rather than primary esophageal structural changes.
*Uncoordinated contractions of the esophagus*
- This indicates **esophageal motility disorders** like **diffuse esophageal spasm** or **achalasia**. While these can cause dysphagia, they are less likely given the systemic features of scleroderma.
- **Achalasia** is characterized by failure of the lower esophageal sphincter to relax and aperistalsis, often from neural degeneration, but it is not typically associated with the widespread systemic findings of scleroderma.
*Outpouching of the lower pharyngeal mucosa and submucosa*
- This describes **Zenker's diverticulum**, which typically causes dysphagia, regurgitation of undigested food, and halitosis, but would not explain the systemic features like skin changes or Raynaud's phenomenon.
- The dysphagia from a Zenker's diverticulum is usually due to mechanical obstruction and pooling of food, rather than a primary motility disorder of the esophagus.
*Protrusion of thin tissue membranes into the esophagus*
- This refers to **esophageal webs**, which most commonly cause intermittent dysphagia to solids, and are often located in the upper esophagus.
- Esophageal webs are not associated with the extensive systemic manifestations present in this patient, such as Raynaud's phenomenon, telangiectasias, or sclerodactyly.
Question 376: A previously healthy 30-year-old woman comes to the physician because of a 6-month history of a recurring rash that typically occurs on exposure to the sun and affects only the face. She also has noticed several nonpainful ulcers on the roof of her mouth. She is sexually active with one male partner and they use condoms inconsistently. Her mother has end-stage renal disease. The patient does not smoke or drink alcohol. Her vital signs are within normal limits. Physical examination shows an erythematous rash across the cheeks that spares the nasolabial folds. There are three small ulcers on the hard palate. Laboratory studies show:
Leukocyte count 3,000/mm3
Platelet count 70,000/mm3
Erythrocyte sedimentation rate 80 mm/h
Serum
Antinuclear antibodies 1:320
Anti-Smith antibodies positive
Urine
Protein 3+
RBC casts negative
RBCs none
WBCs 10–15/hpf
Which of the following is the most appropriate next step in management?
A. Renal biopsy (Correct Answer)
B. Pathergy skin testing
C. Administration of hydroxychloroquine
D. Skin biopsy
E. Administration of azathioprine
Explanation: ***Renal biopsy***
- The patient presents with classic symptoms of **systemic lupus erythematosus (SLE)**, including photosensitive malar rash, oral ulcers, leukopenia, thrombocytopenia, elevated ESR, positive ANA, and positive anti-Smith antibodies. The presence of **proteinuria** (3+) and **pyuria** (WBCs 10-15/hpf) indicates significant renal involvement, likely **lupus nephritis**.
- A **renal biopsy** is essential to determine the **class of lupus nephritis**, which guides treatment and prognosis. This is a critical next step before initiating specific immunosuppressive therapy.
*Pathergy skin testing*
- **Pathergy testing** is used to diagnose **Behcet's disease**, an inflammatory disorder characterized by recurrent oral and genital ulcers, skin lesions, and uveitis.
- While oral ulcers are present, the overall clinical picture, particularly the photosensitive rash, positive ANA and anti-Smith antibodies, and significant hematologic and renal abnormalities, points away from Behcet's disease and towards SLE.
*Administration of hydroxychloroquine*
- **Hydroxychloroquine** is a standard treatment for SLE, particularly for cutaneous symptoms, musculoskeletal involvement, and for preventing disease flares and organ damage.
- However, given the evidence of **significant renal involvement** (proteinuria, pyuria) and the need to classify the lupus nephritis, a renal biopsy is a more immediate and crucial step before initiating general SLE treatment.
*Skin biopsy*
- A **skin biopsy** could confirm lupus-related skin changes (e.g., discoid lupus or subacute cutaneous lupus), but the diagnosis of SLE is already strongly suggested by the other clinical and serological findings.
- A skin biopsy would not provide information about the **severity or type of renal involvement**, which is critical for guiding immediate and specific treatment for lupus nephritis.
*Administration of azathioprine*
- **Azathioprine** is an immunosuppressant used in SLE, particularly for lupus nephritis or other severe organ involvement, often as maintenance therapy or in combination with corticosteroids.
- Similar to hydroxychloroquine, while it may be part of the future treatment plan, initiating this medication without first classifying the **lupus nephritis via renal biopsy** would be premature and potentially suboptimal. The specific class of lupus nephritis determines the most appropriate and aggressive immunosuppressive regimen.
Question 377: A 56-year-old woman presents to the emergency department with muscle weakness. She reports her symptoms have progressively worsened over the course of 2 weeks and are most significant in her lower extremities. She also notices increased urinary frequency. Approximately 1 month ago she was diagnosed with a calcium phosphate nephrolithiasis. Medical history is significant for rheumatoid arthritis diagnosed approximately 10 years ago treated with methotrexate, and type II diabetes mellitus treated with metformin. Her temperature is 98.6°F (37°C), blood pressure is 138/92 mmHg, pulse is 92/min, and respirations are 17/min. On physical exam, there is mild tenderness to palpation of the metacarpophalangeal and proximal interphalangeal joints. There is 4/5 power throughout the lower extremity. Laboratory testing is shown.
Serum:
Na+: 137 mEq/L
Cl-: 106 mEq/L
K+: 2.9 mEq/L
HCO3-: 18 mEq/L
Glucose: 115 mg/dL
Creatinine: 1.0 mg/dL
Urine pH: 5.6
Which of the following is the best next step in management?
A. Administer intravenous sodium bicarbonate
B. Increase the methotrexate dose
C. Administer intravenous insulin
D. Begin potassium replacement therapy with dextrose (Correct Answer)
E. Administer hydrochlorothiazide
Explanation: ***Begin potassium replacement therapy with dextrose***
- The patient presents with **muscle weakness**, **hypokalemia** (2.9 mEq/L), and **metabolic acidosis** (HCO3- 18 mEq/L, normal anion gap since Na - Cl - HCO3 = 137 - 106 - 18 = 13). These findings, along with a history of calcium phosphate nephrolithiasis and relatively alkaline urine (pH 5.6) in the presence of acidosis, point to **distal renal tubular acidosis (Type 1 RTA)**.
- **Potassium replacement** is crucial given the severe hypokalemia, which is likely contributing to the muscle weakness. Potassium is typically administered in dextrose-containing fluids to provide a vehicle for safe intravenous administration and prevent venous irritation from concentrated potassium solutions.
*Administer intravenous sodium bicarbonate*
- While the patient has **metabolic acidosis**, sodium bicarbonate is not the immediate priority and could worsen hypokalemia by driving potassium intracellularly through alkalinization.
- The primary issue is the **renal inability to excrete acid** *and* conserve potassium. Both potassium repletion and bicarbonate therapy will ultimately be needed for Type 1 RTA, but **potassium repletion is the immediate priority** given the severe hypokalemia and muscle weakness.
*Increase the methotrexate dose*
- The patient's **rheumatoid arthritis** is treated with methotrexate, but there is no indication that her current symptoms are related to RA flare or that her methotrexate dose is insufficient.
- Increasing methotrexate would not address the **hypokalemia**, **metabolic acidosis**, or **muscle weakness**.
*Administer intravenous insulin*
- The patient has type II diabetes, but her **blood glucose** (115 mg/dL) is well-controlled and does not warrant immediate intravenous insulin.
- **Insulin would be contraindicated** in this setting as it drives potassium into cells, which would worsen the patient's life-threatening hypokalemia.
*Administer hydrochlorothiazide*
- **Hydrochlorothiazide** is a thiazide diuretic that causes **hypokalemia** and **metabolic alkalosis**.
- Administering hydrochlorothiazide would be contraindicated in this patient as it would exacerbate her existing hypokalemia and would not address the underlying **Type 1 RTA** or metabolic acidosis.
Question 378: A 23-year-old man complains of lower back pain that began approximately 6 months ago. He is unsure why he is experiencing this pain and notices that this pain is worse in the morning after waking up and improves with physical activity. Ibuprofen provides significant relief. He denies bowel and bladder incontinence or erectile dysfunction. Physical exam is notable for decreased chest expansion, decreased spinal range of motion, 5/5 strength in both lower extremities, 2+ patellar reflexes bilaterally, and an absence of saddle anesthesia. Which of the following is the most appropriate next test for this patient?
A. HLA-B27
B. Slit-lamp examination
C. MRI sacroiliac joint
D. Radiograph sacroiliac joint (Correct Answer)
E. ESR
Explanation: **Radiograph sacroiliac joint**
- Plain **radiographs of the sacroiliac (SI) joints** are typically the **initial imaging modality** for suspected **ankylosing spondylitis** due to affordability and diagnostic value.
- They can reveal characteristic changes such as **sacroiliitis (joint erosion, sclerosis, fusion)**, which are common in early-stage disease.
*HLA-B27*
- While a **positive HLA-B27** is associated with ankylosing spondylitis, it is **not diagnostic** on its own, as many HLA-B27 positive individuals never develop the disease.
- Its use is more in **confirming suspicion** or in cases where imaging is equivocal, but it's not the primary diagnostic test.
*Slit-lamp examination*
- A slit-lamp examination is used to detect **uveitis**, which can be an **extra-articular manifestation** of ankylosing spondylitis.
- However, it is not a primary diagnostic test for the condition itself, and its utility arises once the diagnosis is strongly considered or established.
*MRI sacroiliac joint*
- **MRI of the sacroiliac (SI) joints** is more sensitive than radiographs for detecting **early inflammatory changes** (e.g., bone marrow edema) that may not be visible on plain films.
- However, given the duration of symptoms (6 months) and the characteristic inflammatory back pain, **radiographs are typically the first-line imaging** due to cost-effectiveness, reserving MRI for cases with normal radiographs but high clinical suspicion.
*ESR*
- **Erythrocyte sedimentation rate (ESR)** is a **non-specific marker of inflammation** and can be elevated in various inflammatory conditions, including ankylosing spondylitis.
- It is not diagnostic for ankylosing spondylitis and cannot differentiate it from other inflammatory or infectious conditions.
Question 379: A 46-year-old woman presents to the emergency department complaining of abdominal pain, nausea, and vomiting approximately 4 hours after a fatty meal. She reports that this has happened before, but this episode is worse. The vomit was non-bilious and did not contain any blood. She recalls frequent episodes of vague epigastric pain that often wakes her up during the night. Over the counter omeprazole and a small meal or snack would provide some relief in the past. The patient also mentions recent anorexia and early satiety. She takes over the counter ibuprofen several times a week for headaches. Blood pressure is 125/82 mm Hg, pulse is 102/min, and respiratory rate is 19/min. On physical examination, she has hypoactive bowel sounds, and her abdomen seems grossly distended and tympanic on percussion. Which of the following is most consistent with a duodenal ulcer?
A. Early satiety
B. Ibuprofen use
C. Non-bilious vomiting
D. Omeprazole provides relief of the symptoms
E. Food ingestion provides relief of the symptoms (Correct Answer)
Explanation: ***Food ingestion provides relief of the symptoms***
- **Duodenal ulcer pain** is characteristically relieved by eating food, as acid is neutralized or diluted, and the pylorus may spasm, preventing acid from reaching the ulcer.
- The patient's history of relief with a "small meal or snack" is a classic presentation consistent with a duodenal ulcer.
*Early satiety*
- **Early satiety** is more commonly associated with conditions causing gastric outlet obstruction or impaired gastric emptying, such as **gastric ulcers** or malignancy.
- While possible, it is not the most consistent symptom specifically pointing to a duodenal ulcer, whose pain often *improves* with food.
*Ibuprofen use*
- **NSAID use** like ibuprofen can *cause* both gastric and duodenal ulcers by inhibiting prostaglandin synthesis, which protects the gastric and duodenal mucosa.
- However, the question asks what is *most consistent* with a duodenal ulcer among the given options; ibuprofen use is a risk factor, not a direct symptom-relief characteristic.
*Non-bilious vomiting*
- **Non-bilious vomiting** simply indicates that bile has not passed into the stomach, which can occur in various conditions, including non-obstructive causes or proximal obstructions.
- While it can be present, it is not a specific diagnostic feature distinguishing a duodenal ulcer from many other gastrointestinal issues.
*Omeprazole provides relief of the symptoms*
- **Omeprazole** is a **proton pump inhibitor (PPI)** and provides relief for symptoms related to acid production, including both **gastric and duodenal ulcers**, and **gastroesophageal reflux disease (GERD)**.
- Therefore, its effectiveness is not specific enough to definitively point to a duodenal ulcer over other acid-related conditions.
Question 380: A 32-year-old man comes into your office because of pain in his right knee, left elbow, and left wrist. It started about a week ago but has particularly localized to his wrist. The patient states that he has 2 sexual partners. He states he has also had some white discharge from his penis with pruritis and pain during urination. His temperature is 97.6°F (36.4°C), blood pressure is 124/84 mmHg, pulse is 80/min, respirations are 12/min, and oxygen saturation is 98% on room air. Physical exam reveals pain upon palpation of the patient's left wrist which also appears erythematous and swollen. What is the best next step in management for this patient?
A. Ibuprofen and observation
B. MRI
C. Arthrocentesis (Correct Answer)
D. Azithromycin, ceftriaxone, and vancomycin
E. Methotrexate
Explanation: ***Arthrocentesis***
- The patient presents with **migratory polyarthralgia** and then **monoarthritis**, along with symptoms of urethritis and risk factors for sexually transmitted infections (multiple sexual partners). This clinical picture is highly suggestive of **disseminated gonococcal infection (DGI)**, which can cause **septic arthritis**.
- **Arthrocentesis** (joint aspiration) is crucial to obtain joint fluid for analysis (cell count with differential, Gram stain, culture) to confirm the diagnosis of septic arthritis and identify the causative organism, guiding appropriate antibiotic therapy.
*Ibuprofen and observation*
- This approach is insufficient because the patient's symptoms are highly concerning for **septic arthritis**, a medical emergency that requires prompt diagnosis and treatment.
- Delaying definitive diagnosis and treatment of septic arthritis can lead to rapid **joint destruction** and permanent disability.
*MRI*
- An MRI can provide detailed images of the joint structures and surrounding tissues, which is useful in some cases of arthritis.
- However, for suspected septic arthritis, **joint fluid analysis via arthrocentesis** is the gold standard for definitive diagnosis, as it identifies the pathogen and confirms infection. MRI should not delay this critical diagnostic step.
*Azithromycin, ceftriaxone, and vancomycin*
- While this combination might broadly cover common pathogens, starting empiric antibiotics without **first confirming the diagnosis and identifying the organism** through arthrocentesis is not the best first step.
- Vancomycin is for MRSA, and while disseminated gonococcal infection is suspected, **antibiotic sensitivity** is crucial for effective treatment; a Gram stain and culture from joint fluid are needed.
*Methotrexate*
- Methotrexate is a **disease-modifying antirheumatic drug (DMARD)** typically used for chronic inflammatory conditions like rheumatoid arthritis or psoriatic arthritis.
- It is **not indicated for acute septic arthritis**, which requires immediate antibiotics and joint drainage, and its immunosuppressive effects could worsen an active infection.