The Excretion of IgE with Feces from Healthy Individuals and from Others with Allergy and Diseases Affecting the Intestinal Tract

In this study we looked for the occurrence of immunoglobulin E (IgE) in feces from healthy individuals and determined the total daily excretion and day-to-day variation in IgE in feces from patients with allergy, as well as the correlation between concentrations of IgE in small samples of feces and the total amounts of IgE in feces collected over a longer period. Concentrations of IgE in extracts of small samples of dry feces correlated well with the total daily amounts of IgE in feces collected over a 3-day period. Thus, single small samples of feces can be used to measure the excretion of IgE with feces at that time. In 3 children, studied over a 5-week period, the IgE excretion varied somewhat from one day to another, but was largely within a certain range of concentrations. Addition of trypsin inhibitor to fresh feces had no influence on the IgE concentrations of the resulting fecal extracts. Less than 10% of 88 presumably healthy infants, children, and adults had detectable IgE in their feces, while 21 of 40 children with various kinds of allergy had measurable fecal IgE. Only 3 of individuals who were suffering from infectious acute gastroenteritis had IgE-positive fecal extracts. This was also the case for 6 of 25 adult patients in clinical remission of ulcerative colitis or Crohn’s disease. Seven of adult patients with chronic pancreatitis had measurable IgE in feces, and the concentrations were up to ten times the upper limit of IgE found in healthy individuals. Gel filtration experiments showed that fecal IgE from a patient with chronic pancreatitis mainly consisted of fragments corresponding to a molecular weight of approximately 40,000 daltons. Thus, the higher levels of IgE in feces from patients with chronic pancreatitis can only in part be explained by reduced destruction by pancreatic enzymes.