The Irritant Role of Feces in the Genesis of Perianal Itch

Abstract

Summary To learn more about the role of feces in producing perianal pruritus, autogenous fresh feces were applied to the perianal skin of 27 subjects. Itching or definite discomfort developed in 12 (four from a group of 12 with a prior history of anal pruritus, plus eight of 15 with no such history), usually within minutes to a few hours, suggesting an irritant rather than allergic mechanism. Visible changes did not occur. In 10 psychological control subjects, no distress was produced. The therapeutic function of careful but gentle postdefecaLion cleansing is stressed. Other fecal samples adjusted to p H 5.0 and 8.0 were used in conventional and plastic-occluded patch tests on the inner arms. Only a few, mild objective changes occurred and no subjective symptoms, thus confirming the relative sensitivity of perianal skin. Additional observations were also made concerning p H values of perianal skin and casual stool specimens, incidence of yeasts in normal stools, and buffering ability of normal skin.