Histamine intolerance as a cause of chronic digestive complaints in pediatric patients.

INTRODUCTION: histamine intolerance (HI) is a poorly described disease in gastroenterology that may present with predominant digestive complaints. The goals of this study include a report of two cases diagnosed in a pediatric gastroenterology clinic.
MATERIAL AND METHODS: observational, retrospective study of patients diagnosed with HI from September 2010 to December 2011 at the pediatric gastroenterology clinic of a tertiary hospital.They were deemed to have a diagnosis of HI in the presence of 2 or more characteristic digestive complaints, decreased diamino oxidase (DAO) levels and/or response to a low histamine diet with negative IgE-mediated food allergy tests.
RESULTS: sixteen patients were diagnosed. Males predominated versus females (11/5). Mean age at symptom onset was 4 years (6 months vs. 13 years and 6 months) and mean age at diagnosis was 6 years and 6 months (17 months vs. 13 years and 11 months), with an interval of 2 years and 1 month between symptom onset and diagnosis (5 months vs. 4 years). Predominant symptoms included diffuse abdominal pain (16/16), intermittent diarrhea (10/16), headache (5/16), intermittent vomiting (4/16), and skin rash (2/16). The diagnosis was established by measuring plasma diamino oxidase levels, which were below 10 kU/L (normal > 10 kU/L) in 14 cases, and symptom clearance on initiating a low histamine diet. In two patients DAO levels were above 10 kU/L but responded to diet. Treatment was based on a diet low in histamine-contaning food, and antihistamines H1 y H2 had to be added for two cases.
CONCLUSIONS: histamine intolerance is a little known disease with a potentially relevant incidence. Predominant complaints include diffuse abdominal pain, diarrhea, headache, and chronic intermittent vomiting. Its diagnosis is based on clinical suspicion, plasma DAO measurement, and response to a low histamine diet. Management with the latter provides immediate improvement.