Q2: Answer: D
The history of weight loss, intermittent diarrhea, and bloating are suspicious for celiac disease. While lactose intolerance can explain the pain, diarrhea, and bloating, there does not appear to be any correlation with the ingestion of particular foods, nor should there be any weight loss. While inflammatory bowel disease is certainly a possible explanation for his symptoms, it would be premature to jump to upper and lower endoscopy as initial evaluations.
Tissue transglutaminase antibodies are a sensitive and specific screening test for celiac disease, with published sensitivities and specificities greater than 95%. Obtaining a total serum IgA level at the time of screening is recommended to exclude IgA deficiency, which may result in a false-negative test.
Reference
1. Husby S., Koletzko S., Korponay-Szabo I.R., et al. European Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines for the diagnosis of coeliac disease. J Pediatr Gastroenterol Nutr. 2012;54:136-60.
2. Olen O., Gudjonsdottir A., Browaldh L., et al. Antibodies against deamindated gliadin peptides and tissue transglutaminase for diagnosis of pediatric celiac disease. J Pediatr Gastroenterol Nutr. 2012;55:695-700.
