Decreased levels of S-100 protein in non-ulcer interstitial cystitis

Interstitial cystitis (IC) is a chronic debilitating condition which mainly affects women. Accumulated evidence indicates that IC is a heterogeneous s yndrome. As compared to classic IC, the non-ulcer type of IC appears to be different concerning symptomatic, endoscopical and histological findings, a s well as in response to various forms of treatment. S-100 is a neural prot ein considered to be located primarily in the axons. To explore further the neurogenic nature of the disease, we compared bladder wall S-100 content i n controls and in patients with classic and non-ulcer IC. We noticed a decr ease in S-100 content in non-ulcer IC as compared to controls. This may be an expression of altered peripheral innervation in non-ulcer IC, which, in turn, may be an indication of primary neurogenic etiology. The difference i n S-100 content between classic and non-ulcer IC supports the hypothesis th at they represent separate entities, which may explain differences in respo nse to various treatments.