Molecular prevalence of Merkel cell polyomavirus in nonmelanoma skin cancer in a Brazilian population.

BACKGROUND: Merkel cell polyomavirus (MCPyV), a newly described oncogenic virus, has been found in association with tumours other than Merkel cell carcinoma (MCC). As yet, little is known about the involvement or influence of MCPyV on the development of these tumours and its prevalence in various populations. AIM: To assess the prevalence of MCPyV DNA in cases of nonmelanoma skin cancer (NMSC). METHODS: The prevalence of MCPyV DNA was assessed in 96 cases of NMSC in a Brazilian population comprising 76 subjects, and these results were correlated with epidemiological and demographical data. RESULTS: MCPyV DNA was detected in 23 of 69 (33.3%) basal cell carcinomas, in 2 of 11 (18%) squamous cell carcinomas, 2 of 4 Bowen disease case, 0 of 1 MCC and 4 of 11 other skin disorders. CONCLUSION: Despite the frequent detection of MCPyV DNA in NMSC, its possible role in the development of NMSC still needs further investigation.

Pilot Study of Early Monitoring Using Urinary Screening for BK Polyomavirus as a Strategy for Prevention of BKV Nephropathy in Kidney Transplantation.

BACKGROUND: Urine monitoring programs represent an important strategy for early diagnosis of reactivation of BK polyomavirus (BKV) in kidney transplant recipients. This study analyzes a BKV urine screening model in kidney transplant patients. METHODS: Urinary screening for BKV reactivation was performed by urinary decoy cell and polymerase chain reaction (PCR) tests in samples from 32 consecutive kidney transplant patients, collected in a 6-month follow-up period. PCR in plasma samples and BKV immunohistochemical studies to assess BKV renal disease, if a kidney biopsy was indicated, were performed. RESULTS: The urinary screening for BKV among 32 renal receptors was positive in 18 patients (56%) by the concomitant use of the decoy cells and/or qualitative PCR at some time during the study period. Transfusion before transplantation was significantly associated with urinary decoy cell positive screening (odds ratio = 11; 95% confidence interval = 1.47 to 82.4; P < .05); and so was male sex (odds ratio = 2.02; 95% confidence interval = 1.07 to 3.83; P < .05). The clinical management of screening positive cases consisted of decreasing or changing the immunosuppression regimen. Sixteen renal biopsies were performed. Immunohistochemistry for SV40 T antigen was negative in all biopsies. After 1 year of follow-up, no patient developed BKV-associated nephropathy, and there was no difference in renal function between patients positive and negative for BKV urinary screening. CONCLUSIONS: Early urinary monitoring is effective in detection of BKV replication and represents a good strategy to minimize the deleterious effects caused by the presence of the virus on preservation of graft function.

Bizarre nuclei of myocardial fibers in an infant with dilated cardiomyopathy. Light, electron-microscopic, and immunoperoxidase studies of a necropsy case.

The authors present the case of a 9-month-old child with clinical dilated cardiomyopathy that at necropsy showed myocardial cells with volumous, bizarre, and pleomorphic nuclei. These nuclear alterations were also found in other tissues. The myocardial ultrastructural studies revealed degenerative cytoplasmatic changes, nuclear membrane invaginations forming tubules, vesicles, and cytoplasmatic pseudoinclusions, and intranuclear vermicelar bodies, which all suggest virus-induced lesions. Although the ultrastructural studies and immunoperoxidase tests for virus identification were negative, the authors believe that a virus is most probably the agent of these alterations. This case seems to be the first reported on dilated cardiomyopathy with bizarre nuclear alterations in the myocardial fibers having strong evidence pointing to viral etiology.