Cutaneous leishmaniasis in Cavia porcellus (guinea pig): case report / Leishmaniose cutânea em Cavia porcellus (cobaia): relato de caso

Leishmaniasis is a parasitic disease of worldwide spread. It is caused by protozoa of the genus Leishmania and is transmitted to animals and humans through the bite of sand flies. In Brazil, leishmaniasis is one of the zoonoses of major importance and expansion. The objective of this work is to describe the clinical, pathological, immunohistochemical and molecular findings of cutaneous leishmaniasis by Leishmania enriettii in guinea pig (Cavia porcellus). Three animals had nodular and alopecia lesions on the muzzle, ears and ulcerated lesions on the distal extremities of the pelvic limbs. The males (2) also had diffuse thickening of the scrotal skin. Samples of the ulcerated cutaneous lesions were evaluated by cytology which were observed as amastigote forms of Leishmania. One of the animals was euthanized and necropsied. Histopathology showed abundant dermal infiltrate of macrophages, plasma cells, lymphocytes and multinucleated giant cells. Numerous macrophages contained parasitoid vacuoles with amastigote forms, evidenced by immunohistochemical examination. The molecular characterization based on the SSUrDNA gene identified the species as L. enrietti. The diagnosis of cutaneous leishmaniasis in these cases was based on pathological findings and confirmed by immunohistochemistry, PCR and sequencing.(AU)

A leishmaniose é uma doença parasitária de distribuição mundial. É causada por protozoários do gênero Leishmania e é transmitida para animais e seres humanos por meio da picada de flebotomíneos. No Brasil, a leishmaniose é uma das zoonoses de maior importância e expansão. O objetivo deste trabalho é descrever os achados clínicos, patológicos, imuno-histoquímicos e moleculares de leishmaniose cutânea por Leishmania enriettii em cobaia (Cavia porcellus). Três animais apresentavam lesões nodulares e alopécicas no focinho e orelhas, além de lesões ulceradas nas extremidades distais dos membros pélvicos. Nos machos (2), foi observado espessamento difuso da pele escrotal. Amostras das lesões cutâneas ulceradas foram avaliadas por citologia, nas quais foram observadas formas amastigotas de Leishmania. Um dos animais foi submetido à eutanásia e necropsiado. Na histopatologia, foi observado infiltrado dérmico abundante de macrófagos, plasmócitos, linfócitos e com células gigantes multinucleadas. Numerosos macrófagos continham vacúolos parasitóforos com formas amastigotas, evidenciados por meio do exame de imuno-histoquímica. A caracterização molecular baseada no gene de SSUrDNA identificou a espécie como L. enrietti. O diagnóstico de leishmaniose cutânea nesses casos foi baseado nos achados patológicos e confirmado pelas técnicas de imuno-histoquímica, PCR e sequenciamento.(AU)

Cocaine/levamisole-induced systemic vasculitis with retiform purpura and pauci-immune glomerulonephritis

Levamisole has been increasingly used as an adulterant of cocaine in recent years, emerging as a public health challenge worldwide. Levamisole-associated toxicity manifests clinically as a systemic vasculitis, consisting of cutaneous, hematological, and renal lesions, among others. Purpura retiform, cutaneous necrosis, intravascular thrombosis, neutropenia, and less commonly crescentic nephritis have been described in association with anti-neutrophil cytoplasmic antibodies (ANCAs) and other autoantibodies. Here we report the case of a 49-year-old male who was a chronic cocaine user, and who presented spontaneous weight loss, arthralgia, and 3 weeks before admission purpuric skin lesions in the earlobes and in the anterior thighs. His laboratory tests on admission showed serum creatinine of 4.56 mg/dL, white blood count 3,800/μL, hemoglobin 7.3 g/dL, urinalysis with 51 white blood cells/μL and 960 red blood cells/μL, and urine protein-to-creatinine ratio 1.20. Serum ANCA testing was positive (>1:320), as well as serum anti-myeloperoxidase and anti-proteinase 3 antibodies. Urine toxicology screen was positive for cocaine and levamisole, with 62.8% of cocaine, 32.2% of levamisole, and 5% of an unidentified substance. Skin and renal biopsies were diagnostic for leukocytoclastic vasculitis and pauci-immune crescentic glomerulonephritis, respectively. The patient showed a good clinical response to cocaine abstinence, and use of corticosteroids and intravenous cyclophosphamide. Last serum creatinine was 1.97 mg/dL, white blood cell count 7,420/μL, and hemoglobin level 10.8 g/dL. In levamisole-induced systemic vasculitis, the early institution of cocaine abstinence, concomitant with the use of immunosuppressive drugs in severe cases, may prevent permanent end organ damage and associate with better clinical outcomes.

Multiple facets of HIV-associated renal disease

HIV infection has a broad spectrum of renal manifestations. This study examined the clinical and histological manifestations of HIV-associated renal disease, and predictors of renal outcomes. Sixty-one (64% male, mean age 45 years) HIV patients were retrospectively evaluated. Clinical presentation and renal histopathology were assessed, as well as CD4 T-cell count and viral load. The predictive value of histological lesion, baseline CD4 cell count and viral load for end-stage renal disease (ESRD) or death were determined using the Cox regression model. The outcomes of chronic kidney disease (CKD) and ESRD or death were evaluated by baseline CD4 cell count. The percent distribution at initial clinical presentation was non-nephrotic proteinuria (54%), acute kidney injury (28%), nephrotic syndrome (23%), and chronic kidney disease (22%). Focal segmental glomerulosclerosis (28%), mainly the collapsing form (HIVAN), acute interstitial nephritis (AIN) (26%), and immune complex-mediated glomerulonephritis (ICGN) (25%) were the predominant renal histology. Baseline CD4 cell count ≥200 cells/mm3 was a protective factor against CKD (hazard ratio=0.997; 95%CI=0.994-0.999; P=0.012). At last follow-up, 64% of patients with baseline CD4 ≥200 cells/mm3 had eGFR >60 mL·min-1·(1.73 m2)-1 compared to the other 35% of patients who presented with CD4 <200 cells/mm3 (log rank=9.043, P=0.003). In conclusion, the main histological lesion of HIV-associated renal disease was HIVAN, followed by AIN and ICGN. These findings reinforce the need to biopsy HIV patients with kidney impairment and/or proteinuria. Baseline CD4 cell count ≥200 cells/mm3 was associated with better renal function after 2 years of follow-up.