Encrusted cystitis and pyelitis

Purpose: Encrusted cystitis and pyelitis are chronic inflammations of the bladder and collecting system associated with mucosal encrustations induced by urea splitting bacteria. We review these infectious diseases. Materials and methods: A literature search was performed of the MEDLINE database from 1985 to 1997. Additional articles published before 1985 were also selectively included. Results: Most of the articles were case reports or short series. During the last 10 years increasing numbers of cases have been diagnosed, especially in immunodepressed patients, particularly in renal transplant recipients. Many bacteria have been demonstrated in this infection but Corynebacterium group D2 is currently the most frequent. The development of encrusted cystitis or pyelitis requires the presence of specific bacteria with an alkaline urine, a preexisting urological procedure and a clinical context predisposing to infection. Clinical diagnosis can be difficult but the presence of alkaline urine containing abundant calcified mucopurulent debris is highly suggestive. Demonstration of the bacteria requires prolonged cultures in enriched media. Treatment is based on adapted antibiotic therapy, acidification of urine and excision of plaques of calcified encrustation. The consequences of treatment failure are serious and can result in graft nephrectomy in kidney transplant recipients. Conclusions: Early clinical and bacterial diagnosis of encrusted cystitis and pyelitis could improve the prognosis of these infectious diseases.