Ticarcillin-induced cystitis. Cross-reactivity with related penicillins.

Two children had dysuria, sterile pyuria, and microscopic hematuria develop during treatment with ticarcillin disodium. With the exception of a predominance of pyuria over hematuria, the clinical course and laboratory findings in this disorder were similar to those observed in hemorrhagic cystitis, a potential complication of the use of several semisynthetic penicillins and penicillin G potassium. One patient had urinary abnormalities develop during two courses of ticarcillin therapy and subsequently after initiation of piperacillin sodium therapy. A second patient in whom hemorrhagic cystitis due to carbenicillin disodium developed experienced this related disorder four years later when first exposed to ticarcillin. Neither reduction of the dose nor substitution of one semisynthetic penicillin for another (piperacillin for ticarcillin, ticarcillin for carbenicillin) prevented recurrence of the disorder. The clinical importance of either form of cystitis induced by semisynthetic penicillins is uncertain, as is the risk for progression to interstitial nephritis.