Effect of sex hormones on gentamicin-induced nephrotoxicity in rats

1. There is clinical and experimental evidence that females are more susceptible to gentamicin-induced nephrotoxicity. To assess the role of sex as a risk factor in aminoglycoside-related acute renal failure 16 groups of five 120 +/- 15-day old (young adult) Wistar rats of both sexes, castrated and non-castrated, were treated with gentamicin. These rats were medicated with 40 mg kg-1 24 h-1 gentamicin alone for 10 days. Some animals received gentamicin after 5 days of treatment with depot testosterone or estrogens. 2. Blood urea and creatinine levels before and after gentamicin administration were measured to evaluate renal function. Histological lesions were studied by light microscopy by two pathologists who were unaware of the group. Rats with normal or elevated levels of estrogens showed functional impairment after gentamicin. A poor correlation was detected between levels of urea/creatinine and histopathological findings. 3. Lesions were considerably more severe in females. Testosterone administration to intact animals offered partial protection against the renal effects of gentamicin in both sexes. In contrast, estradiol administered to intact animals was regularly associated with significantly more severe lesions in both males and females. Castration by itself attenuated the gentamicin-induced renal alterations in males, but not in females. These data provide support for an unfavorable effect of estrogens rather than a favorable effect of testosterone. The demonstration of more severe lesions in female castrated rats when compared with male castrated rats indicates the participation of other factors, possibly of a genetic nature, in the pathogenesis of gentamicin-induced renal lesions

Glomerulosclerose segmentar e focal: estudo de 23 casos. / Segmental and focal glomerulosclerosis: a study of 23 cases

Em 516 biopsias renais examinadas por microscopia optica, foram definidos 23 casos de glomerulosclerose segmentar e focal. O quadro clinico usual apresentou-se ora como sindrome nefrotica, ora como proteinuria assintomatica acompanhadas ou nao de hipertensao arterial ou hematuria. A evolucao da doenca variou entre progressao rapida para insufisiencia renal cronica, estabilizacao, recidiva e remissoes sucessivas ou remissoes prolongadas.Houve associacao da lesao com infeccoes das vias aereas superiores, passado de glomerulonefrite aguda, toxemia gravidica e lupus eritematoso sistemico. Com apoio na microscopia optica, a glomerulosclerose segmentar e focal nao parece estar estritamente associada ao quadro clinico, a evolucao e ao prognostico

Nefrite intersticial aguda: relato de dois casos. / Acute interstitial nephritis: report of two cases

A nefrite intersticial aguda e causa pouco reconhecida de insuficiencia renal aguda em nosso meio, conquanto suas multiplas possibilidades etiologicas sugiram incidencia mais marcante.Sao apresentados dois casos de insuficiencia renal aguda com evolucao favoravel, superponivel a usualmente observada na necrose tubular aguda, cujas biopsias renais revelaram comprometimento predominante do intersticio. O primeiro caso foi consequente a erisipela, enquanto o segundo ocorreu em menina com fortes antecedentes alergicos e em uso de carbamazepina

Sindrome nefrotica e lesao minima gromerular em criancas. Estudo por imunofluorescencia. / Nephrotic syndrome and minimal glomerular lesion in children. An immunofluorescence study

No periodo de junho de 1976 a dezembro de 1978 foram estudados 44 pacientes portadores de glomerulopatias primarias. Todos foram submetidos a biopsia renal percutanea e, alem de microscopia optica, foi realizado estudo imuno-histoquimico do material. Do grupo foram selecionados 20 pacientes que eram portadores de lesao minima glomerular. O estudo imuno-histoquimico revelou presenca de depositos mesangiais em 8 criancas, ficando demonstrado, desta maneira, que a associacao de lesao minima com ausencia de deposito nao e absoluta. Nao foi demonstrada tambem relacao entre a presenca de depositos e a evolucao desfavoravel dos pacientes