Polyomavirus nephropathy and Cytomegalovirus nephritis in renal allograft recipients.

Background: Polyomavirus nephropathy (PVN) and Cytomegalovirus (CMV) disease are the most common viral pathogens causing allograft dysfunction in renal allograft recipients. They have been observed in transplant recipients with increasing frequency in the recent years with various reports describing wide differences in the incidence of these infections in renal allografts. We present our experience with Polyomavirus (PV) infection and CMV infection in allograft of renal transplant recipients from a transplant centre in North India performing more than 100 transplants per year. Materials and Methods: 390 renal allograft specimens from 327 patients over a 4 year period, presenting with renal dysfunction were re-evaluated for presence of PVN and CMV disease utilizing histo-morphological features and immunohistochemistry. Results: Thirteen patients with PVN and four with CMV disease were identified. All patients were on triple drug immunosuppression receiving cyclosporine, prednisolone and tacrolimus or MMF. The mean period of diagnosis of viral infection after transplant was 12.4 months (seven days to 3.5 yrs) for PVN and 4.8 months (two to seven months) for CMV nephritis. Biopsies showed varying degrees of tubulointerstitial inflammation, viral inclusions and evidence of tubular damage. Associated features of acute rejection were present in 69.2% of patients with PVN. Conclusion: Histological features of PVN involving the kidneys have considerable morphological overlap with acute rejection while CMV disease presents primarily as tubulointerstitial inflammation. We observed a prevalence of 4% for PVN and 1.2% for CMV nephritis in renal allografts.

Localized amyloidosis of urinary bladder: a diagnostic dilemma.

Amyloidosis is a heterogeneous group of disorders affecting a single-or multiple-organ system and presents as generalized or localized disease. Both generalized amyloidosis and localized amyloidosis can be primary or secondary. Localized amyloidosis affects organs like urinary bladder, lung, larynx, skin, tongue and the region around the eye, producing detectable nodular masses which are clinically suspected as malignancy. We present six cases of localized urinary bladder amyloidosis that were clinically and cystoscopically suspected as bladder tumor or cystitis, which occurred over a period of last 10 years. Histology in all cases revealed diagnosis of primary amyloidosis. None of them had any stigmata of secondary disease. The cases were treated by simple transurethral resection of bladder. Two out of the six cases recurred after 3 to 5 years of initial presentation and were asymptomatic thereafter. Amyloidosis of the bladder is a rare condition which often mimics bladder neoplasm clinically and cystoscopically and histological examination is a must for definite diagnosis and proper management.

Pneumocystis carinii pneumonia after renal transplantation.

Being immuno-suppressed, renal allograft recipients are at increased risk of contracting various infectious complications. Pneumocystis carinii pneumonia (PCP) is one of the important opportunistic infection causing high morbidity and mortality in these patients. Majority of studies has reported the occurrence of PCP during 6 months to one year after renal transplantation. This communication describes occurrence of PCP in five renal allograft recipients 10 weeks to 72 months after transplantation. In view of elusive presentation, strong clinical and radiological suspicion followed by direct demonstration of the organisms is essential for early diagnosis and prompt treatment. These observations also indicate that PCP is an emerging opportunistic infection in immuno-compromised patients in tropical countries.