Encrusted cystitis by Corynebacterium urealyticum: a case report with novel insights into bladder lesions.

Corynebacterium urealyticum (CU) (formerly Corynebacterium group D2) is a gram-positive bacillus with a strong urease activity that can infect the lower (acute or chronic cystitis) and upper (pyelonephritis and encrusted pyelitis) urinary tract . CU is a commensal skin organism that an estimated 12% of healthy individuals carry and it has been isolated in 30% of hospitalized patients. CU converts urea into ammonia, creating alkaline urine, which precipitates struvite and calcium phosphate crystals, forming stones and encrustations on the infected mucosa. In a patient with EC, we investigated whether the calcification might be an active process regulated by osteogenic proteins using immunohistochemical studies to analyse osteonectin, osteopontin and osteocalcin deposition in encrusted bladder tissue.