Histological changes and immunolabeling ofLeishmania infantum in kidneys and urinary bladder of dogs

Abstract

The aim of this study was to assess histological alterations and perform immunolabeling of Leishmania infantum in the kidneys and urinary bladder of naturally infected dogs. Twenty-five urinary bladder and kidney samples of serologically positive animals (ELISA S7® Biogene and IFAT ≥ 1:40 -Biomanguinhos/Fiocruz) were analyzed by means of immunohistochemical and histological techniques. Cystitis was found in 44% (11/25) of the bladder samples and membranoproliferative glomerulonephritis in 92% (23/25) of the kidney samples. Immunolabeling of the parasite revealed that 32% (8/25) of the bladders and 8% (2/25) of the kidneys were positive. In conclusion, the immunohistochemical technique is a useful tool for detecting amastigote forms of L. infantum in organs of infected dogs. In addition, this was the first report of detection of amastigote forms of L. infantum in the bladders of dogs.Keywords: Leishmania infantum, immunohistochemistry, nephropathy, cystitis, dog. ResumoObjetivou-se neste estudo avaliar as alterações histológicas e realizar a imunomarcação de Leishmania infantum em rins e bexiga de cães naturalmente infectados. Vinte e cinco amostras de bexiga e rins de animais sorologicamente (ELISA S7® Biogene and IFAT ≥ 1:40 -Biomanguinhos/Fiocruz) positivas foram analisadas histologicamente e por meio da técnica de imuno-histoquímica. Os resultados revelaram cistite em 44% (11/25) das amostras de bexiga e glomerulonefrite membranoproliferativa em 92% (23/25) das amostras de rins. A imunomarcação do parasito revelou 32% (8/25) e 8% (2/25) de positividade em bexiga e rins, respectivamente. Conclui-se que a técnica de imunohistoquímica é uma útil ferramenta para detecção de formas amastigotas de L. infantum em órgãos de cães infectados. Além disso, o presente trabalho reporta a primeira descrição de formas amastigotas de L. infantum em bexiga de cães.

Laboratory tests for diagnosing and monitoring canine leishmaniasis

“…The interpretation of clinicopathologic, serologic, and molecular tests should take into account the history (eg, exposure to phlebotomine vectors), signalment (male dogs > 2 years are at high risk), and clinical presentation. The latter is characterized by a wide spectrum of clinical presentations, ranging from infections characterized by the absence of overt clinical findings in the presence of obvious laboratory abnormalities, to more or less marked clinical and laboratory abnormalities that may require hospitalization, especially in cases with severe life‐threatening complications …”

“…The deposition of circulating immune complexes at the glomerular level induces inflammatory changes detectable histologically and ultramicroscopically, leading to a proteinuric nephropathy . The resulting chronic kidney disease (CKD) is characterized by glomerulosclerosis, renal hypertension, and tubulointerstitial nephritis .…”

“…The latter is characterized by a wide spectrum of clinical presentations, ranging from infections characterized by the absence of overt clinical findings in the presence of obvious laboratory abnormalities, to more or less marked clinical and laboratory abnormalities that may require hospitalization, especially in cases with severe life-threatening complications. [14][15][16][17][18][19][20][21][22][23][24][25][26]…”

“…The interpretation of histologic results is well documented by numerous publications describing the typical lesions and the distribution of parasites associated with active disease, mostly characterized by lymphoplasmacytic or granulomatous-pyogranulomatous inflammation and/or by vasculitis either in organs usually affected by Leishmania (bone marrow, spleen, skin, lymph nodes, kidney, etc), and also in unusual tissues such as heart, lung, adrenal gland, genital tract, central nervous system, skeletal muscle, gastrointestinal tract, nails, lacrimal glands, and ocular muscles. [19][20][21]23,26,50,55,56,58,60,61,98,160,[172][173][174][175][176][177][178][179][180][181] Parasite culture and biologic test for infectiousness (xenodiagnosis)…”

Evaluation of the serum biochemistry and histopathology of kidney and bladder of dogs with Leishmania sp. in their urine

“…reaches the urine through the bladder. Additionally, a study by Santos et al (2013) observed immunostained Leishmania sp. in 32% of the bladder samples, and in only 8% of the kidney samples.…”