A 13-year-old boy is brought to the office due to poor weight gain. His mother also notes that he is the shortest student in his class. The patient has occasional abdominal discomfort and a bloating sensation but has a good appetite and eats a balanced diet. He has had no nausea, vomiting, diarrhea, hematochezia, or melena. The patient has a 3-year history of type 1 diabetes, and his insulin was recently decreased due to recurrent episodes of hypoglycemia. Family history is significant for hypothyroidism in the mother. Vital signs are within normal limits. Weight is at the 5th percentile for age and height is at the 10th. Physical examination shows anicteric sclera, moist mucous membranes, no enlarged lymph nodes, and normal heart and lung sounds. The abdomen is nondistended, soft, and nontender with no organomegaly. Laboratory results are as follows: Which of the following is the best next step in evaluation of this patient?

Question

A 13-year-old boy is brought to the office due to poor weight gain.  His mother also notes that he is the shortest student in his class.  The patient has occasional abdominal discomfort and a bloating sensation but has a good appetite and eats a balanced diet.  He has had no nausea, vomiting, diarrhea, hematochezia, or melena.  The patient has a 3-year history of type 1 diabetes, and his insulin was recently decreased due to recurrent episodes of hypoglycemia.  Family history is significant for hypothyroidism in the mother.  Vital signs are within normal limits.  Weight is at the 5th percentile for age and height is at the 10th.  Physical examination shows anicteric sclera, moist mucous membranes, no enlarged lymph nodes, and normal heart and lung sounds.  The abdomen is nondistended, soft, and nontender with no organomegaly.  Laboratory results are as follows:  Which of the following is the best next step in evaluation of this patient?

Quizplus · Accepted Answer

This adolescent with type 1 diabetes is in a low height and weight percentile, and the development of recurrent hypoglycemia and reduced insulin requirements suggest malnutrition despite adequate oral intake. Given his abdominal discomfort and microcytic anemia, this presentation raises suspicion for celiac disease. Celiac disease is a chronic malabsorptive disorder of the small bowel caused by immune-mediated hypersensitivity to gluten. Patients with type 1 diabetes are at particularly high risk of celiac disease, possibly related to multiple shared genetic loci between these 2 autoimmune conditions. In addition to autoimmunity (eg, autoimmune thyroiditis, family history of autoimmune disease), another risk factor strongly associated with celiac disease is Down syndrome. In the pediatric population, growth delay is often the initial sign. Gastrointestinal symptoms are nonspecific; although diarrhea is classic, patients may have bloating or abdominal discomfort. Other clinical findings include vitamin and nutrient deficiencies from malabsorption: iron-deficiency microcytic anemia is particularly common. Diagnosis can be made serologically (eg, antitissue transglutaminase antibody, anti-endomysial antibody) or by duodenal biopsy (eg, intraepithelial lymphocytosis, villous blunting). Management includes a gluten-free diet. (Choice B) Abdominal CT scan can evaluate for intraabdominal malignancy, which can cause weight loss. In particular, pancreatic cancer is associated with diabetes mellitus (although predominantly type 2 diabetes in adults). However, patients typically have anorexia and normocytic (rather than microcytic) anemia of chronic disease. In this young patient with multiple risk factors, celiac disease is more likely; CT scan could be considered if further workup is unrevealing. (Choice C) Fecal fat testing is used to diagnose fat malabsorption. However, this typically causes steatorrhea (eg, greasy, large volume stool). Although celiac disease can lead to fat malabsorption, fecal fat testing is nonspecific and may be positive in multiple disorders (eg, chronic pancreatitis, prior intestinal surgery). (Choice D) Serum insulin-like growth factor 1 is used to diagnose growth hormone deficiency, which can cause pediatric growth delay but would not explain this patient's microcytic anemia or gastrointestinal symptoms. (Choice E) Sweat chloride testing is used to diagnose cystic fibrosis, which often causes growth delay and diabetes but is typically associated with pulmonary symptoms (eg, cough, dyspnea) and steatorrhea. Educational objective: Celiac disease is a chronic malabsorptive disorder caused by an immune-mediated hypersensitivity to gluten; patients with certain autoimmune diseases (eg, type 1 diabetes, autoimmune thyroiditis) are at particularly high risk. Pediatric patients often have growth delay, nonspecific gastrointestinal symptoms, and microcytic anemia. The diagnosis can be confirmed serologically with anti-tissue transglutaminase antibodies or by duodenal biopsy. References: Type 1 diabetes and celiac disease: clinical overlap and new insights into disease pathogenesis. (http://www.ncbi.nlm.nih.gov/pubmed/24952108)

A 13-Year-Old Boy Is Brought to the Office Due to Poor