Abstract. Although the nephropathy of visceral leishmaniasis (VL) is known both in humans and dogs, histopathologic alterations have not been thoroughly studied. We examined renal alterations in 55 dogs with naturally acquired VL compared with five noninfected dogs from an endemic area in northeastern Brazil. Glomerulonephritis was found in 55 dogs, interstitial alterations in 53 dogs, and tubular changes in 43 dogs with VL. The glomerular alterations found were minor glomerular abnormalities (n ϭ 8, 14.5%), focal segmental glomerulosclerosis (n ϭ 10, 18.2%), mesangial proliferative glomerulonephritis (n ϭ 17, 32.7%), membranoproliferative glomerulonephritis ,(n ϭ 18, 30.9%), crescentic glomerulonephritis (n ϭ 1, 1.8%), and chronic glomerulonephritis (n ϭ 1, 1.8%). Morphometric and ultrastructural studies complemented the analysis. The five control animals exhibited no glomerular alterations. The glomerular lesions were related to functional alterations. Considering that the alterations of canine and human nephropathy in VL are very similar, the data obtained in this study constitute an important contribution to the understanding of canine and human VL nephropathy.Key words: Dogs; glomerulonephritis; morphometry; renal pathology; ultrastructure; visceral leishmaniasis.Canine visceral leishmaniasis (VL) is a highly prevalent infection encountered throughout the world. In Brazil, VL results from infection by the protozoan Leishmania (Leishmania) chagasi, which occurs in 18 of 27 Brazilian states. 20,22,26 VL is endemic to northeastern Brazil, and in Teresina, in the State of Piaui, some 1,600 dogs presenting naturally acquired VL were known when this study was initiated. At present, VL is also spreading to other urban areas in the southern and southeast regions, where the disease was not previously endemic. 31 In the infectious cycle of VL, the dog is the most important domestic reservoir and exhibits chronic evolution of the disease. 1,8,21 Leishmania is an obligatory intracellular parasite of mononuclear phagocytes. During infection, various host organs are affected including the kidney. Although VL-related nephropathy is known both in humans and dogs, the histopathologic patterns of the lesions present in VL have not been clearly established because most studies are based on very few cases and mainly because well-defined, lesion classification criteria were not used. 3,4,9,10,24,37,38 In human VL, glomerulosclerosis, mesangial cell proliferation, and interstitial nephritis have been reported. 3,9,10,16,18,38 Renal involvement in canine VL is also frequent, and the renal changes are similar to those seen in humans. 2,5,8,23,32 This similarity renders the study of canine VL nephropathy of interest with regard to human pathology. The renal lesion itself does not lead to renal insufficiency. However, when moderate or severe renal lesions are present, VL patients with systemic complications such as secondary infections, sepsis, and hypotension do develop renal insufficiency. 16 Furthermore, glomerular lesions appare...

Abstract. Conidiobolomycosis is reported in the state of Piauí, in the semiarid region of northeastern Brazil. Affected sheep had depression, weight loss, serous or mucohemorrhagic nasal discharge, and cranium-facial asymmetry from exophthalmos of 1 eye, generally with increased volume of the eyeball, keratitis, and corneal ulceration. At necropsy of 60 sheep, friable masses were observed in the posterior region of the nasal cavity, often destroying the ethmoturbinate bones. Frequently, the lesions invaded the nasal sinuses, cribiform plate, orbit, and brain. The masses were irregular, granular with moist surfaces, and soft and friable with white, yellow, or tan coloration. Dissemination of the lesion to lungs was observed in 27 sheep, to the brain in 26, to lymph nodes in 3, to the kidney in 2, and to the gallbladder and heart in 1. The microscopic examination showed granulomatous inflammation composed of central necrosis surrounded by lymphocytes, epithelioid and giant cells, and fibrous tissue. In all lesions, negatively stained structures representing hyphae were surrounded by Splendore-Hoeppli material. Coagulative necrosis, thrombosis, and vasculitis were also observed. Grocott methenamine silver stain showed 8-30-mm-thick hyphae, rarely septate or ramified, irregular in shape, and with black contoured wall, sometimes with bulbous dilatation in the extremities. On electron microscopy, the hyphae had a thick double wall surrounded by cellular remnants and an inflammatory exudate. Conidiobolus coronatus was isolated from the lesions of 6 sheep. Conidiobolomycosis is an important disease of sheep in the state of Piauí, and other regions of northeastern Brazil.