Interstitial cells of Cajal network in primary obstructive megaureter.

OBJECTIVES: Recent reports showed an altered density of interstitial cells of Cajal (ICCs) and of peripherin immunoreactive nerve fibres in obstructed uretero-pelvic junction. Our aim was to investigate ICCs immunoexpression and ureteral innervation in primary obstructive megaureter (POM). METHODS: 8 specimens of POM were obtained during tailoring. Restricted segments of ureters were divided from the dilated ones. C-kit and peripherin immunohistochemistry were performed. RESULTS: A normal distribution of ICCs was documented in both circular and longitudinal muscular layers of dilated segments. Marked muscular hypoplasia and a sparse or absent ICCs occurred in longitudinal muscular layer of restricted ureteral segments. A normal distribution of peripherin positive fibres was present in both dilated and restricted segments. CONCLUSIONS: Our data confirmed a defective muscolarization in restricted, aperistaltic POM. The lacking of ICCs in the longitudinal muscular layer is, probably, due to the absence of c-kit positive muscular embryological precursors. No alteration of peripherin immunoreactive nerve fibres network was observed in both dilated and restricted ureteral segments.