Secondary effects of aganglionosis in the piebald-lethal mouse model of Hirschsprung's disease.

An attempt was made to identify the factors secondary to fecal stasis and megacolon that are related to overall debilitation and eventual death of the piebald mouse. The piebald mouse showed periodic leukocytosis and bacteremia that were associated with lesions in the mucosal surface of the megacolon. Defective growth, loss of weight, and retardation of development with megacolon were documented by systematic study of body weight and of the relationship between body weight and organ weights. Alterations in body weight and in organ weight to body weight ratios were parallel in the piebald mouse, in mice with imperforate anus, and in mice with surgically-induced megacolon. Histologic studies confirmed a pattern of hypertrophy of the muscularis externa in the piebald mouse. The body temperature was lower than for normal siblings, but the sodium, potassium, and water content of the feces, the general blood chemistry profiles, and the intestinal microflora did not differ from those of the normal mouse. There was no evidence of bacterial overgrowth in the small intestine of the piebald mouse with fecal stasis and megacolon.