A 13-year-old girl is brought to the office due to intermittent abdominal pain for the past 2 months. The pain is "around the belly button" and tends to occur after eating. For breakfast, she usually has cereal with milk, after which she "passes a lot of gas." The patient says, "I feel embarrassed when my friends and I go out for dessert after school. Last night, after I finished ice cream in a waffle cone, I had to run to the bathroom immediately because I had watery diarrhea." She is a vegetarian and has not had similar symptoms with other foods, including fruits, vegetables, eggs, yogurt, and grilled cheese sandwiches. The patient has been taking oral minocycline for acne for the past year. She also has seasonal allergies, for which she takes oral loratadine; her asthma has been well controlled with oral montelukast and inhaled corticosteroids. Menarche occurred at age 12; her last menstrual period was 2 weeks ago. Weight is 45.4 kg (100 lb, 15th percentile), unchanged since her last appointment 6 months ago. Height is 155 cm (5 ft 1 in, 10th percentile), increased from 150 cm (4 ft 11 in). Blood pressure is 110/68 mm Hg and pulse is 70/min. Physical examination shows small comedones and pustules on the forehead and chin. The lungs are clear to auscultation. Normoactive bowel sounds are heard, and the abdomen is soft, nontender, and nondistended. There is no hepatosplenomegaly. Which of the following is the most appropriate strategy in management of this patient?

Question

A 13-year-old girl is brought to the office due to intermittent abdominal pain for the past 2 months.  The pain is "around the belly button" and tends to occur after eating.  For breakfast, she usually has cereal with milk, after which she "passes a lot of gas."  The patient says, "I feel embarrassed when my friends and I go out for dessert after school.  Last night, after I finished ice cream in a waffle cone, I had to run to the bathroom immediately because I had watery diarrhea."  She is a vegetarian and has not had similar symptoms with other foods, including fruits, vegetables, eggs, yogurt, and grilled cheese sandwiches.  The patient has been taking oral minocycline for acne for the past year.  She also has seasonal allergies, for which she takes oral loratadine; her asthma has been well controlled with oral montelukast and inhaled corticosteroids.  Menarche occurred at age 12; her last menstrual period was 2 weeks ago.  Weight is 45.4 kg (100 lb, 15th percentile), unchanged since her last appointment 6 months ago.  Height is 155 cm (5 ft 1 in, 10th percentile), increased from 150 cm (4 ft 11 in).  Blood pressure is 110/68 mm Hg and pulse is 70/min.  Physical examination shows small comedones and pustules on the forehead and chin.  The lungs are clear to auscultation.  Normoactive bowel sounds are heard, and the abdomen is soft, nontender, and nondistended.  There is no hepatosplenomegaly.  Which of the following is the most appropriate strategy in management of this patient?

Quizplus · Accepted Answer

Explanation: 11ec2b69_c159_a2a6_8f63_635708e38192_MD0005_00 Lactose intolerance most commonly occurs secondary to the genetic reduction of lactase, a duodenal brush border enzyme that breaks down ingested lactose into glucose and galactose. This condition is more prevalent with increasing age, especially among Asian and African American populations. Presentation includes periumbilical abdominal pain, bloating, flatulence, and watery diarrhea. Milk and ice cream have a high lactose content, and symptoms often develop soon after ingestion. Cheese and live-culture yogurt, however, have less lactose content and tend to cause few or no symptoms. Diagnosis is clinical and can be confirmed by the resolution of symptoms on a lactose-restricted diet. Formal testing can be performed by the lactose breath hydrogen test, which measures excessive lactose fermentation and hydrogen production by colonic bacteria. Most patients with lactose intolerance can tolerate small amounts of dietary lactose with or without supplemental lactase, so full elimination is not typically required. All patients should also be counseled on maintaining adequate vitamin D and calcium intake. (Choice B) Minocycline is a tetracycline antibiotic often used in the treatment of acne. Although many antibiotics can cause diarrhea (eg, amoxicillin clavulanate) through alteration of intestinal flora, minocycline is not classically associated with diarrhea. In addition, this patient has symptoms temporally related to dairy intake. (Choice C) Dietary restriction of gluten is indicated in confirmed celiac disease, which can also present with gastrointestinal distress (eg, abdominal pain, flatulence, diarrhea). However, patients typically have growth failure and/or weight loss, which this patient does not have. (Choice D) Esomeprazole, a proton pump inhibitor, is indicated for gastroesophageal reflux disease. Presentation includes epigastric pain with regurgitation and heartburn; common triggers include fatty foods, caffeine, and spicy foods. Although reflux disease could be triggered by high-fat dairy foods, it would not explain this patient's flatulence or diarrhea. (Choice E) Loperamide is an antidiarrheal used commonly in patients with irritable bowel syndrome. This medication may inhibit peristalsis; however, it does not address or treat the underlying mechanism of lactose intolerance in this patient. Educational objective: Lactose intolerance classically presents with periumbilical abdominal pain, flatulence/bloating, and diarrhea. Suspicion of intolerance can be confirmed with resolution of symptoms on a lactose-restricted diet or by lactose breath hydrogen test. References: Lactose intolerance: from diagnosis to correct management. (http://www.ncbi.nlm.nih.gov/pubmed/24443063)

A 13-Year-Old Girl Is Brought to the Office Due to Intermittent