Rp. Kapur et al., HYPOTHESIS - PATHOGENESIS OF SKIP AREAS IN LONG-SEGMENT HIRSCHSPRUNGS-DISEASE, PEDIATRIC PATHOLOGY & LABORATORY MEDICINE, 15(1), 1995, pp. 23-37
The existence of skip areas in a subset of patients with long-segment
Hirschsprung's disease (LSHD) is a rare phenomenon that poses practica
l and theoretical challenges. In this paper, three new cases are descr
ibed and compared with preceding reports in the medical literature. In
addition, an analogous distribution of ganglion cell precursors is re
ported in the developing large intestines of murine embryos, homozygou
s for the lethal spotted (ls) allele. In ls/ls embryos which were dest
ined to have ''classic'' short-segment aganglionosis coli, a transient
phase was observed in which ganglion cells were present in the middle
colon, but absent from the cecum and distal large intestine. This ''s
kip area'' is attributed to an extramural phase of neuroblast migratio
n which is unique to the colon. Persistence of an abnormal pattern of
neuroblast migration, similar to that observed transiently in ls/ls em
bryos, is invoked as an explanation for skip areas in humans with LSHD
.