MAST-CELL AND SUBSTANCE P-POSITIVE NERVE INVOLVEMENT IN A PATIENT WITH BOTH IRRITABLE-BOWEL-SYNDROME AND INTERSTITIAL CYSTITIS

Many patients with interstitial cystitis (IC) also have irritable bowe r syndrome (IBS), both of which occur overwhelmingly in women, are cha racterized by pain, and worsen under stress. Bladder and colon biopsie s of a female patient with both IC and IBS were evaluated immunohistoc hemically. There were 40 +/- 10 mast cells (MC)/mm(2) (normal, less th an 10) in the bladder, which were degranulated. The colon contained 14 8 +/- 11 MC/mm(2) (normal, less than 50), mostly close to numerous sub stance P (SP)-positive nerves, Histamine, methylhistamine, and the uni que MC enzyme tryptase were elevated in 24-hour urine during two flare -ups. These results may help explain the concurrent presentation and t he painful nature of these syndromes.