Adenoma of bladder in siblings with renal dysplasia.

A huge tumor filled the lumen of the urinary bladder in a ten-year-old boy. The tumor had polypoid and papillary components with a variety of glandular structures. Some glands were surrounded by a primitive stroma reminiscent of renal dysplasia, a new finding in adenoma (or mixed hamartoma) of the urinary bladder. A couple of months later a large tumor filling the urinary bladder and with the same microscopic features was diagnosed in his fourteen-year-old brother.

Urine cytology as a screening method for polyoma virus active infection.

Polyoma virus nephropathy (PVN) occurs in 3% to 4% of renal transplants, causing graft loss in about 50% of cases. The presence of viral cytopathic changes in graft epithelial cells is the only diagnostic tool for PVN. However, identification of cells with viral inclusions (decoy cells) in urine can be used as a screening tool for viral replication of or for active infection with PV. The aim of the present study was to identify the occurrence of PV active infection in renal transplant recipients. Two hundred forty urine cytology samples, collected from 80 transplant patients with stable renal function, were collected on a monthly basis and stained with the Pap smear for decoy cells. Active infection with polyoma virus was confirmed by urine immunostaining. All samples were analyzed blindly and classified as negative or positive (>1 decoy cell/sample). Among 240 urine cytologies collected from 48 men and 32 women, decoy cells were identified in 37.5%. No differences were observed in serum creatinine or immunosuppressive regimen between patients with positive versus negative cytology. No graft losses occurred secondary to PVN in the present study setting. The incidence of decoy cells in this series (37.5%) was consistent with previous reports (20% to 40%), suggesting that active infection may be confirmed by PV immunohistochemistry. The absence of PVN in this group may be attributed to the low doses of immunosuppressive drugs in the late posttransplant transplant period, but also to the unknown incidence of polyoma virus infection in Brazil.

Argyrophilic nucleolar organizer region (AgNOR) technique: a helpful tool for differential diagnosis in urinary cytology.

The aim of this study was to investigate whether the AgNOR technique could be helpful for the cytologic diagnosis of neoplastic and non-neoplastic urinary tract lesions. We analysed the AgNOR pattern in urinary cytology in samples from 70 patients. In every case the average number of silver precipitations per nucleus was counted and the range between the minimum and maximum AgNOR value calculated. Furthermore we noted whether the AgNOR precipitations had a homogeneous or heterogeneous distribution. The diseases were classified in three groups: non-neoplastic lesions, low grade and high grade carcinoma. Linear discriminant analysis (with jack-knife procedure) was performed with the AgNOR parameters as independent variables. The final diagnosis of each patient had been established by histological analysis of bladder biopsies. We obtained a correct classification in 84.3% of the cases. All patients with normal or reactive lesions were correctly classified and only two cases of low grade malignancy were erroneously diagnosed as non-malignant. Five high grade neoplasms had been classified as low grade and four low grade carcinomas had been over-diagnosed as high grade neoplasms. We conclude that a combined qualitative and quantitative AgNOR analysis can be useful in the differential diagnosis of urinary cytology.