A 38-year-old man comes to the physician with intermittent abdominal pain for several months. The pain is in the epigastric area and is often worse with food intake. He has tried over-the-counter antacids and H2 blockers with minimal relief. He reports occasional nausea but denies vomiting, hematemesis, or melena.
His past medical history is significant for asthma diagnosed 2 years ago, for which he uses an albuterol inhaler. Two months ago, he was hospitalized for pneumonia and asthma exacerbation and was treated with steroids and antibiotics. The patient immigrated to the United States 5 years ago from Laos. He does not use tobacco, alcohol, or illicit drugs. He denies HIV risk factors and known exposure to tuberculosis.
His temperature is 36.7 C (98 F), blood pressure is 122/70 mm Hg, and pulse is 77/min. Physical examination is unremarkable.
Laboratory results are as follows:

Serum chemistry and liver function tests are normal. Chest CT is unremarkable. Two stool samples for ova and parasites are negative.
What is the best next step in management of this patient?

Question

A 38-year-old man comes to the physician with intermittent abdominal pain for several months.  The pain is in the epigastric area and is often worse with food intake.  He has tried over-the-counter antacids and H2 blockers with minimal relief.  He reports occasional nausea but denies vomiting, hematemesis, or melena.
His past medical history is significant for asthma diagnosed 2 years ago, for which he uses an albuterol inhaler.  Two months ago, he was hospitalized for pneumonia and asthma exacerbation and was treated with steroids and antibiotics.  The patient immigrated to the United States 5 years ago from Laos.  He does not use tobacco, alcohol, or illicit drugs.  He denies HIV risk factors and known exposure to tuberculosis.
His temperature is 36.7 C (98 F), blood pressure is 122/70 mm Hg, and pulse is 77/min.  Physical examination is unremarkable.
Laboratory results are as follows:

Serum chemistry and liver function tests are normal.  Chest CT is unremarkable.  Two stool samples for ova and parasites are negative.
What is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec193a_9855_09a8_853d_f9b7432a24f6_MD0002_00 This patient's presentation of abdominal pain, recent history of pneumonia, peripheral eosinophilia, and endemic area for Strongyloides stercoralis suggests strongyloidiasis. The parasite is prevalent in the southeastern United States and Southeast Asia (eg, Laos, Cambodia). Infection usually begins with larvae from infected soil penetrating the human skin through the feet. The larvae then migrate hematogenously into the lungs and up the tracheobronchial tree, where they are swallowed. The larvae enter the intestine and mature into adult worms, which produce eggs that transform into larvae. The larvae are then excreted in feces. The full cycle takes about 3-4 weeks. However, S stercoralis can produce larvae that mature completely in the intestine to complete the entire life cycle within the human host. This leads to autoinfection with a large worm burden and hyperinfection syndrome, usually in immunocompromised individuals. The larvae can disseminate into the lungs, liver, heart, central nervous system, and endocrine glands to cause shock or multiorgan failure. The hyperinfection syndrome can also lead to Gram-negative bacteremia (eg, Escherichia coli) due to hematogenous seeding of organisms from the GI tract. As a result, patients from endemic areas with unexplained Gram-negative bacteremia should be tested for S stercoralis. Patients with strongyloidosis may be asymptomatic or present with intermittent abdominal pain, pulmonary symptoms misdiagnosed as asthma that usually worsen with corticosteroids, and/or cutaneous signs. Diagnosis can be confirmed by larvae detection in stool, but stool studies can often be negative. Serology (ELISA for IgG) can be positive even in patients with negative stool studies. Suspected patients with 2 negative stool samples and serology testing may require duodenal aspiration, the string test (Entero-Test), or empiric treatment with ivermectin (preferred) or albendazole (alternate). (Choice A) Initial evaluation of a patient with mild peripheral eosinophilia (< 1500 cells/µL) should begin with detailed history, examination of stool for ova and parasites, and serologic tests based on exposure and travel to endemic areas. Bone marrow biopsy may be indicated if these tests are negative. (Choice B) Celiac disease may present with diarrhea but usually has evidence of iron deficiency anemia. However, this patient's pulmonary symptoms and eosinophilia make this diagnosis less likely. (Choice C) Helicobacter pylori testing is indicated in patients with dyspepsia, gastric MALT lymphoma, or history of active peptic ulcer disease. (Choice E) GI symptoms are unlikely in patients with allergic bronchopulmonary aspergillosis. CT scan usually shows fleeting infiltrates and/or bronchiectasis. Educational objective: Strongyloidiasis should be suspected in patients presenting with peripheral eosinophilia, GI and pulmonary complaints, and exposure to an endemic area. Invasive Strongyloides infection can lead to multiorgan dysfunction and septic shock. Diagnosis includes at least 2 stool samples (often negative), ELISA test for IgG antibody, and/or duodenal aspirate/biopsy. Treatment involves ivermectin or albendazole. __________ References: Maltreatment of strongyloides infection: case series and worldwide physicians-in-training survey. (http://www.ncbi.nlm.nih.gov/pubmed/17524758) Management of strongyloides in immigrants and refugees: is serologic testing useful?. (http://www.ncbi.nlm.nih.gov/pubmed/19407125)

A 38-Year-Old Man Comes to the Physician with Intermittent Abdominal