Canine leishmaniosis caused by Leishmania infantum is a disease with a wide range of clinical manifestations. Epidemiological serosurveys performed in Europe often lack a thorough assessment of clinical health status of studied dogs. The aim of this study was to evaluate signalment, immunological and parasitological status and clinicopathological findings of L. infantum-seropositive apparently healthy dogs (n = 212) living in endemic areas. Routine laboratory tests, endpoint in-house ELISA to quantify the anti-Leishmania antibodies, blood Leishmania qPCR and IFN-γ ELISA were performed. All dogs enrolled were L. infantum-seropositive and were classified as healthy (n = 105) or sick (n = 107) according to LeishVet guidelines. The sick group presented a higher proportion of medium to high antibody levels and positive qPCR and lower IFN-γ concentration compared to the healthy group. Sick dogs were mostly classified in LeishVet stage IIa. Biochemical alterations (98%) were the most common clinicopathological findings, with fewer urinary tract (46%) and hematological (40%) alterations. Apparently healthy L. infantum-seropositive dogs can be classified between truly healthy dogs and sick dogs with clinicopathological findings. Sick dogs presented medium to high seropositivity and parasitemia and low IFN-γ concentrations, and their most common clinicopathological abnormalities were serum protein alterations followed by proteinuria and lymphopenia.

Dogs are the main reservoir of Leishmania infantum and display different immunological patterns correlating with the progression of infection to disease. Data about feline L. infantum adaptive immune response are scant. This study aimed to compare the prevalence and immune response in cats and dogs from the same endemic area of canine leishmaniosis. Stray cats (109) and rescued dogs (59) from Córdoba (Spain) were enrolled. Data about their exposure to L. infantum were analyzed by detection of parasite DNA, measurements of Leishmania-specific interferon-γ (whole blood assay in 57 cats and 29 dogs), and antibodies (enzyme-linked immunosorbent assay and immunofluorescence antibody test). An overall L. infantum prevalence of 30.5% in dogs and 30% in cats were found according to serology and PCR tests. Prevalence was 44.8% in dogs and 35.1% in cats tested also for interferon-γ production. Dogs showed higher anti-L. infantum antibody levels compared to cats. More than one-third of cats had contact with or were infected by L. infantum and they may contribute to the endemicity of leishmaniosis in the investigated region. The immunopathogenesis of feline L. infantum infection has similarities with dogs but cats show a lower level of adaptive immune response compared to dogs.

Neutrophil-to-lymphocyte (NLR), monocyte-to-lymphocyte (MLR), and platelet-to-lymphocyte (PLR) ratios have been proposed as diagnostic and prognostic markers for neoplastic and inflammatory diseases in dogs and cats. The aim of this retrospective preliminary study was to evaluate the relationship between these ratios and markers of inflammation routinely measured in cats. A total of 275 cats were enrolled. Complete blood count, serum amyloid A (SAA), albumin, globulin, and albumin-to-globulin ratio (AGR) data were analyzed, as well as the presence of leukocyte alterations considered suggestive of inflammation (LAI: neutrophils left shift, toxic neutrophils, and reactive lymphocytes) evaluated in blood smears. The NLR and MLR correlated positively with SAA and globulins and negatively with albumin and AGR. Higher NLR and MLR were found in cats with increased SAA and globulins and decreased albumin and AGR. The PLR correlated negatively with albumin and AGR. A higher PLR was found in cats with hypoalbuminemia. Cats with LAI had higher NLR, MLR, and PLR. In cats with no changes in parameters indicative of inflammation, 11.25, 0.42, and 528.3 were identified as upper limits for NLR, MLR, and PLR, respectively. In conclusion, the NLR, MLR, and PLR act as good inflammatory markers easily evaluated by routine hematology.

Background: Feline leishmaniosis caused by Leishmania infantum is often associated with feline immunodeficiency virus (FIV) infection; however, the role and clinical significance of this coinfection remain unknown. This study aimed to assess whether FIV is associated with L. infantum infection in cats from canine leishmaniosis endemic areas and to report the clinical signs and hematological alterations associated with coinfection. Methods: A retrospective matched case-control study (ratio 1:2) was conducted. Data of clinical examination and complete blood count (CBC) were selected from a cohort of 705 cats examined for epidemiological studies on feline leishmaniosis conducted between 2012 and 2019. Ninety-one FIV seropositive cases and 182 FIV seronegative control cats were selected. Matching was done according to age, sex, lifestyle and geographic provenience of case cats. Rapid ELISA devices were mainly used to detect anti-FIV antibodies. Anti-Leishmania IgG antibodies were detected by indirect-immunofluorescence test (IFAT). Leishmania DNA was searched in blood, oral and conjunctival swabs by quantitative real-time PCR. Results: Feline immunodeficiency virus seropositive cats had no hematological abnormalities suggestive of an advanced stage of FIV infection and were statistically more frequently IFAT positive, and their risk of being L. infantum antibody positive was 2.8 greater than in the FIV seronegatives. The association of FIV seropositivity with L. infantum antibody positivity was confirmed in the univariable model of logistic regression. A multivariate model found FIV infection and L. infantum PCR positivity as predictors of a positive L. infantum IFAT result. Male outdoor cats from rural or suburban areas were at risk for FIV and L. infantum antibody positivity. Clinical signs more frequently associated with the coinfection were oral lesions, pale mucous membranes and low body condition score (BCS). Conclusions: This study documents that FIV seropositive cats with no hematological abnormalities suggestive of an advanced stage of FIV infection are more prone to be L. infantum seroreactive by IFAT in endemic areas. Therefore, FIV seropositive cats should be tested for L. infantum antibodies and treated for preventing sand fly bites. Pale mucous membranes, low BCS and oral lesions but no CBC abnormalities were significantly associated with the coinfection. Graphical

Background: Domperidone (Leisguard^®) is an immunomodulatory drug used as a preventive measure in healthy dogs. However, no studies have been published in healthyLeishmania infantum-seropositive dogs. The aim of this study was to evaluate the clinical efficacy and safety of domperidone as immunotherapy inLeishmania-seropositive healthy dogs.Methods: Sixty-seven dogs were treated with domperidone at 0.5 mg/kg and 44 dogs received placebo, once daily for 4 consecutive weeks. Monthly treatments were repeated every 4 months until the end of the 1-year follow-up period. Veterinary examinations were performed on days 0, 30, 120, 150, 240, 270 and 360. Samples of blood and urine were collected on days 0, 120, 240 and 360 for routine laboratory tests and quantitative in-house ELISA for the detection ofL. infantum-specific antibodies. Furthermore,Leishmaniareal-time PCR and IFN-γ ELISA were performed at day 0 and the end of the study. Dogs that developed disease were withdrawn from the study and classified as sick dogs. Adverse drug reactions were reported.Results: Thirty dogs developed disease during the follow-up period: 13/67 (19.4%) in the group treated with domperidone and 17/44 (38.6%) in the placebo-treated group (P = 0.03). Low-seropositive dogs treated with domperidone (4/40, 9.1%) were significantly less likely to develop disease compared to low-seropositive dogs treated with placebo (7/24, 29.2%;P = 0.04), while no differences were found between domperidone (9/23, 39.1%) and placebo (10/20, 50%) in medium- to high-seropositive dogs. At the end of the study, a higher proportion ofLeishmaniaPCR-positive dogs was observed in the placebo-treated group (16/33, 48.5%) compared to the domperidone group (13/51, 25.5%;P = 0.04). Furthermore, low-seropositive dogs treated with domperidone with an increase of IFN-γ concentration presented a higher increase than those treated with placebo at the end of the study. Four dogs treated with domperidone presented self-limiting diarrhea.Conclusions: Healthy dogs with lowL. infantumantibody levels treated with domperidone were less likely to develop disease compared to placebo-treated dogs. Furthermore, domperidone presented a good safety profile.Graphical

Leptospirosis is a worldwide zoonotic disease, but feline leptospirosis is rarely reported. This study aimed at investigating Leptospira spp. prevalence in cats from southern Italy, evaluating risk factors, clinical findings and laboratory data associated with infection. The serum of 112 cats was investigated by microscopic agglutination test (MAT), detecting anti-Leptospira antibodies against 14 pathogenic serovars. Blood and urine samples were tested by a real-time polymerase chain reaction targeting the lipL32 gene of pathogenic Leptospira. Antibodies against serovars Poi, Bratislava, Arborea, Ballum, Pomona and Lora were detected in 15.3% (17/111) of cats (titers range: 20–320). Leptospira spp. DNA was found in 3% (4/109) of blood and 9% (10/111) of urine samples. The spring season was the only risk factor for urinary Leptospira DNA shedding. Laboratory abnormalities significantly associated and/or correlated with Leptospira spp. positivity were anemia, monocytosis, neutrophilia, eosinopenia, increased alanine aminotransferase activity, hypoalbuminemia and hyperglobulinemia. In the investigated areas, cats are frequently infected by Leptospira spp. and can represent an additional reservoir or sentinel for a risk of infection. Moreover, some laboratory changes could be compatible with a pathogenic effect of Leptospira spp. in the feline host.