Mast cell involvement in interstitial cystitis.

A prospective study was designed to examine the relationship of mast cells, and eosinophilic leukocyte density and mediator levels to clinical and histological parameters of interstitial cystitis. Interstitial cystitis and control patients underwent bladder biopsy with histological examination, and quantification of intact and degranulated mast cell and eosinophilic leukocyte density. In addition, bladder tissue histamine content, urinary prostaglandin E2 excretion rates, and serum and urinary major basic protein levels were determined. A strong relationship among detrusor mast cell density, especially degranulated, and degree of epithelial loss, submucosal inflammation, epithelial ulceration, urinary pyuria and response to treatment was noted. Bladder tissue histamine content and urinary prostaglandin E2 excretion were increased in the interstitial cystitis patients. Eosinophil density in bladder biopsies was low uniformly, and interstitial cystitis and control patients showed no statistical difference. In addition, serum and urinary major basic protein levels were below the accepted normal lower limits for this protein. Therefore, our study demonstrates a relationship between the mast cell and the inflammatory process of interstitial cystitis. No similar relationship was noted for the eosinophil.