Chronic diarrhea associated with hypogammaglobulinemia and enteropathy in infants and children.

In order to define the gastrointestinal manifestations and small intestinal structure and function in a group of infants with chronic nonspecific diarrhea and hypogammaglobulinemia, we retrospectively identified 55 such patients from a population of 518 children evaluated for chronic diarrhea over a 6-year span (10.6%). All patients had IgG levels 2.0 SD or more below the mean values for age. Patients with biochemical evidence of protein loss (enteropathy or nephropathy) were excluded. There was a 50% incidence of small intestinal mucosal injury among these patients, with a spectrum of morphological findings ranging from healing enteritis to severe active enteritis. Carbohydrate malasorption, and infection with Giardia lamblia or Clostridium difficile occurred in 34% and 24% of patients tested, respectively. These structural, functional, and infectious complications were all statistically more common in patients than in a control group of children with chronic diarrhea, normal growth, and normal immunoglobulin levels. This study suggests that immunoglobulin determination, in children who would otherwise carry a diagnosis of chronic nonspecific diarrhea, identifies a group with hypogammaglobulinemia, having an increased incidence of treatable intestinal dysfunction or infection, and a spectrum of small intestinal histologic abnormalities.