The piebald-lethal murine strain: investigation of the cause of early death.

Forty-eight piebald-lethal (PL) mice with distal aganglionosis and 42 normal littermates (LM) were studied to determine the cause of early death. PL mice were noted to be smaller than their LM and to have normal albumin and immunoglobulin levels for the first 30 days of age. As PL mice aged, a significant decline in albumin with a concomitant rise in immunoglobulin levels was demonstratable. Systemic sepsis with enteric organisms was found in 10% of sacrificed PL mice and in 38% of spontaneously dying PL animals. Histologic examination of PL aganglionic and ganglionic colon demonstrated no evidence of enterocolitis. Ganglionic colon of PL mice contained a flattened, thinned mucosa. The early death of PL mice is related to generalized debilitation from prolonged distal colonic obstruction resulting in a decrease in immunologic integrity and an increased susceptibility to sepsis.