Identificação de Leptospira spp. através de técnicas histológicas no tecido renal de pequenos mamíferos não voadores

Abstract

The present work aimed to diagnose Leptospira spp. in renal tissue of non-flying wild mammals of the Paranaíba river region, in order to detect the bacteria in the kidney of these animals of the Brazilian Cerrado. Sixty-eight renal tissue samples from non-flying wild mammals of the Rio Paranaíba region were used. Histopathological staining techniques such as Alcian Blue and silver impregnation using the Warthin-Starry technique were also performed besides the Hematoxylin-Eosin for the detection of kidney damage caused by this agent. The samples used had already been tested in PCR, for the presence of Leptospira spp., by evidence of Lipl32. Blood serum from each of the 68 animals was tested in dark field microscopic agglutination (MAT) for serological diagnosis. The results of PCR and MAT were compared with the results of renal lesions found in each sample. Hematoxylin-Eosin staining detected around 36,76% lesions in mammalian renal tissue, and interstitial nephritis with lymphoplasmic inflammatory infiltrate was the most common alteration. Warthin-Starry staining by silver nitrate impregnation showed the presence of Leptospira spp. in about 7,35% while in the Alcian Blue technique the presence of the agent was found in about 4,41% samples. The presence of the agent as well as the evidence of microscopic alterations would be a great finding, thus being possible to relate the bacteria with lesions caused in the renal tissue. There were lesions in the renal tissues of non-flying mammals of the Cerrado, indicating probable infection. HE staining made it possible to identify characteristic lesions of the infection suggestive of leptospirosis, while Alcian Blue and Warthin-Starry stains showed the presence of Leptospira spp..