Diffuse Intralobular Liver Fibrosis in Dogs Naturally Infected with Leishmania (Leishmania) chagasi

Abstract

The aim of this study was to evaluate the diffuse intralobular fibrosis in dogs naturally infected with Leishmania (Leishmania) chagasi. One hundred five infected animals with positive serologic tests for Leishmania were divided into two clinical groups: 69 symptomatic animals and 36 asymptomatic. Special staining with Gomori, Heidenhain, Silver, and Picrosirius Red was applied to characterize fibrilopoesis. The tissue parasite load was measured by immunohistochemistry and associated histomorphometric analyses. Intralobular fibrosis was observed in all dogs, and more collagen deposition was confirmed in the infected animals than in the controls by these histomorphometric studies. There were significant differences among the distinct clinical groups. In fact, symptomatic dogs showed an increased collagen deposition in the liver compared with asymptomatic ones. A peculiar diffuse intralobular fibrosis, where the collagen fibers encircled small groups of hepatocyte(s), was observed in two cases (1.9%).

Expression of Toll-like receptors 2 and 9 in cells of dog jejunum and colon naturally infected with Leishmania infantum

“…For semi-quantitative analysis, inflammatory mononuclear cells were counted using ocular analysis and rated: (1) Slight: 1–9 cells per field/20 fields; (2) moderate: 10–30 cells per field/20 fields; (3) intense: > 30 cells per field/20 fields. For quantitative analysis, images were analyzed using software, viewed on a computer video screen, and transferred to a computer-assisted image analysis system (Kontron Elektronic/Carl Zeiss, Germany) [49]. Under microscopic analysis, a minimum of 20 fields for each slide mounted with paraffinized GIT segment fragments was counted.…”

Effect of Ambient Temperature on the Clinical Manifestations of Experimental Diffuse Cutaneous Leishmaniasis in a Rodent Model

“…In contrast, in cold and dry conditions, even when inflammation at the inoculation site was seen, a dry exfoliative squamous dermatitis with hair loss until alopecia was noted, starting at the inguen and spreading mainly to the back of the mice until it reached the face. This type of dermatitis has been reported for dogs (Binhazim et al 1992;Brachelente et al 2005;Melo et al 2008;Travi et al 2009), and felines (Solano-Gallego et al 2007) infected with L. infantum. In humans, this may be similar to the post-kala-azar dermal leishmaniasis caused by L. infantum (Zijlstra et al 1995) or L. donovani after treatment (Das et al 2009).…”

“…In fact, the only exception was the brain. The distribution of Leishmania in several organs has been documented for visceral Leishmania acquired naturally by dogs, giving rise to the following pathogenic conditions: colitis (Adamama-Moraitou et al 2007), nephropathy (Costa et al 2003), liver fibrosis (Melo et al 2008), genital lesions (Diniz et al 2005), and transplacental transmission of parasites (Pangrazio et al 2009). This indicates a broad spectrum for this disease, which may be true for dermal species as well.…”

Histopathological and parasitological study of the gastrointestinal tract of dogs naturally infected with Leishmania infantum

“…CVL infection is considerably more prevalent than clinical illness in endemic areas; this has been reported both in Brazil and Europe (Mediterranean basin countries) [7-13]. Furthermore, clinical signs of the disease are highly variable and can include lymphadenopathy [14,15], skin lesions [16-18], progressive weight loss [19], hepatosplenomegaly [20,21], ocular and musculoskeletal abnormalities, renal disease and epistaxis [22-24]. …”