Successful treatment of encrusted cystitis and pyelitis with preservation of renal graft.

Abstract

Opportunistic infection by Corynebacterium urealyticum, or Corynebacterium group D2 (CGD2), is found in approximately 3% of immunosuppressed transplant patients, leading to complications such as encrusted cystitis and pyelitis (i.e., stone encrustations and inflammation of the bladder and renal pelvis due to the presence of urea-splitting organisms in the urine), as well as graft failure (1–4). We present the first known successfully treated pediatric case of encrusted cystitis and pyelitis in a renal transplant patient. An 8-year-old boy presented with abdominal pain, urgency, and gross hematuria in 3/00. He was status postrecent admission for an acute exacerbation of chronic pneumonia for which he received stress dose steroids. His medical history was significant for prune belly syndrome with obstructive uropathy leading to end stage renal disease and subsequent cadaveric renal transplant at age 4. At age 7, he underwent an ureterocystoplasty with appendicovesicostomy. A computerized axial tomogram (CT) on admission revealed calcifications throughout the bladder and renal pelvis; these findings were corroborated by ultrasound. The patient was initially treated with IV ciprofloxacin and aggressively hydrated, with his FK506 held to decrease immunosuppression. Initial cultures were negative; subsequent ones were positive for CGD2, but in numbers we felt were insignificant in a patient on intermittent catheterization. However, after repeat urine culture confirmed the presence of CGD2 in larger colony counts, the patient was diagnosed with encrusted cystitis and pyelitis, and vancomycin was added to his treatment regimen. Creatinine on admission was 1.4 mg/dl; white blood cell count was 5,600/μl with 12 bands. With hydration and antibiotics, the patient’s hematuria and pain resolved. One month after presentation, the patient underwent cystoscopy, ureteroscopy, and open debridement of his bladder plaques (Fig. 1). Intraoperative urine cultures were negative for Corynebacterium, but a postoperative CT revealed residual kidney calcifications. Vancomycin was continued, and percutaneous acidification of the collecting system was started with 25% Thomas’ solution at 20 cc/hr at 20 cmH2O. This regimen continued for two months. Follow-up imaging revealed total resolution of bladder and renal lesions. Subsequent cultures revealed no further signs of Corynebacterium infection. The patient’s creatinine fell to 1.3 mg/dl from a peak of 1.7 mg/dl.FIGURE 1.: Calcified plaques found during open debridement of bladder.The patient’s clinical history satisfied many of the risk factors for encrusted cystitis and pyelitis. As a transplant recipient, he was vulnerable due to his state of immunosuppression; this was exacerbated by the bolus of stress dose steroids that he had received in his prior admission (1,2,4). Urine cultures revealed the presence of CGD2 infection, classically associated with alkalinization of the urine (1–4). Additionally, the patient had under-gone a number of urological proce-dures, including an ureterocystoplasty with appendicovesicostomy that presumably created multiple mucosal lesions. Interestingly, the nidus for his bladder lesions was intraoperatively discovered to be an area of necrosed tissue in the region of his previous bladder augmentation. Successful treatment of pediatric and adult CGD2 infections should include: prolonged antibiotic course with vancomycin, glycopeptides, or teicoplanin; excision of bladder plaques; urinary acidification; and close follow-up to prevent recurrence. Such infections may be minimized by removing genitourinary instrumentation, such as stents, as quickly as possible after urological procedures (5).