Feline leishmaniosis: diagnosis, treatment and outcome in 16 cats

Abstract

Objectives Leishmaniosis is a vector-borne disease and in European countries is caused by Leishmania infantum. Cats are considered secondary reservoirs of the infection in endemic areas. The objective of this retrospective study is to describe the clinical findings, diagnosis, treatment and outcome of feline leishmaniosis (FeL) in 16 cats in Spain. Methods Medical records of cats diagnosed with leishmaniosis were retrospectively reviewed for cases that met the following inclusion criteria: identification of Leishmania organisms and/or DNA on cytological and/or histological specimens and/or a high anti- Leishmania antibody titre, compatible clinical findings and pathological abnormalities. Results Sixteen cats met the inclusion criteria, all of which were living in areas endemic for canine leishmaniosis. Systemic signs were present in 11 cases (68.8%). The most common clinical signs on presentation included cutaneous lesions in 12 cats (75%), ocular disease in six cats (37.5%) and anorexia in six cats (37.5%). A polyclonal gammopathy was noted in 12 cats (85.7%). Non-regenerative anaemia and renal abnormalities were present in six (37.5%) and five patients (31.3%), respectively. In nine cats (56.3%), immunosuppressive conditions/comorbidities were identified. The diagnosis was made in eight of the cats (50%) by cytology, but a combination of diagnostic tests was needed for definitive diagnosis in the remaining patients. Twelve cats (75%) were treated specifically for leishmaniosis. Five of the 12 cats (41.7%) did not improve with treatment. The median survival time in the group of patients treated specifically for leishmaniosis was 17 months. Median survival of patients treated with concomitant diseases was 13 months vs 41 months in those without, although this was not statistically significant ( P = 0.557). Conclusions and relevance Presentation of FeL appears to be similar to canine leishmaniosis but with some specific features: ulcerative and nodular skin lesions are the predominant cutaneous signs; cats with immunosuppressive conditions or co-existing diseases were more commonly present than typically seen in dogs (mainly feline immunodeficiency virus). A combination of diagnostic tests may be needed for definitive diagnosis.

Feline Leishmania spp. Infection in a Non-Endemic Area of Northern Italy

“…Most infected cats showed solitary or generalized lymphadenomegaly and gingivostomatitis was the second most common clinical sign in the infected cats. When clinical signs of FeL are present, they are non-specific and frequently similar to those in other feline diseases and subclinical L. infantum feline infection is common [1,2,4,5,25,26,44,45]. The remaining subjects, 3/10 infected cats showed no clinical abnormalities and seemed to be apparently healthy and this corroborates the reports that FeL infected cats can be asymptomatic and that subclinical feline infection L. infantum is common [1,2,4,5,25,26,[44][45][46][47].…”

“…A significant association between FIV and L. infantum infections has been found in previous studies [17,34,51,54] and also in stray cat populations in Milan investigated in a previous study [7]. FIV was previously reported to be the most frequent concomitant coinfection in FeL infected cats [1,5]. However, this significant association was not seen in the current study.…”

“…Mild to severe CBC abnormalities such as normocytic normochromic non-regenerative anemia, moderate to severe pancytopenia or leucocytosis may be seen in L. infantum infected cats [1,4,5,30,48,49]. Most infected cats in the current study had CBC parameters outside the reference range for healthy cats, however no significant statistical difference was reported in CBC median value between infected and uninfected cats.…”

“…While median alpha 2-globulins remain in reference range in FeL infected cats, median gamma-globulins increased more in infected than in uninfected cats. Gammopathy are found in most cases described in the literature [1,4,5,18,30,[48][49][50][51][52] with some cats showing also a normal proteinemia as in the feline population analyzed in this study. It can be hypothesized that in cats, as in dogs, the humoral immune response could also be activated by the production of immunoglobulins after infection, resulting in high concentrations of gamma-globulins.…”

“…In endemic regions such as Mediterranean countries, the subclinical form of feline L. infantum is common, whereas clinical illness is relatively uncommon [1,2,4,5]. Sandflies are the natural vectors of Leishmania spp.…”