The conservative management of corynebacterium group D2 encrusted pyelitis

To evaluate the conservative management of encrusted pyelitis (EP), an infectious disease caused by urea-splitting micro-organisms (Corynebacterium group D2 being the most common), and characterized by stone encrustation of the collecting system.

Four patients (aged 17-62 years) with EP caused by Corynebacterium group D2 were treated conservatively with intravenous vancomycin and percutaneous acidification of the renal collecting system. Percutaneous nephrostomy tubes were placed to allow irrigation with Thomas' acid solution, the outflow being ensured by ureteric catheters. Patients were monitored and the results of and tolerance to treatment evaluated clinically, by biological assays, and by imaging techniques (ultrasonography, computed tomography and pyelography).

No kidneys were lost and in all patients with initial renal failure, creatinine levels recovered to previous values. The adverse effects were moderate, consisting of flank pain or discomfort, and low-grade fever. Three patients developed asymptomatic fungal urinary tract infections requiring antifungal agents. The encrustations were treated effectively and almost disappeared in two patients, while the other two had no residual calcification. One transplanted-kidney recipient developed a ureteric stricture requiring surgical repair. Within a mean follow-up of 16 months, there was no recurrence of EP and the residual encrustation remained small.

The conservative treatment of EP can avoid surgery in many cases, although there are some adverse effects of irrigation. The long-term follow-up and prevention of recurrent EP are nevertheless required.