title: Evaluation of indirect immunofluorescence antibody test and enzyme-linked immunosorbent assay for the diagnosis of infection by Leishmania infantum in clinically normal and sick cats.
abstract: Cats that live in areas where canine and human leishmaniosis due to Leishmania infantum is endemic may become infected and may develop anti-Leishmania antibodies. In this study 50 clinically normal and 50 cats with cutaneous and/or systemic signs that lived in an endemic area and had been previously examined for infection by L. infantum using PCR in four different tissues were serologically tested for the presence of anti-Leishmania IgG (IFAT and ELISA) and IgM (IFAT). The aim was to compare the results of IFAT, ELISA and PCR and to investigate the possible associations between seropositivity to Leishmania spp and signalment, living conditions, season of sampling, health status of the cats, and seropositivity to other infectious agents. Low concentrations of anti-Leishmania IgG were detected by IFAT in 10% of the cats and by ELISA in 1%, whereas anti-Leishmania IgM were detected by IFAT in 1%. There was disagreement between the results of IFAT and ELISA for anti-Leishmania IgG (P = 0.039) and between all serological tests and PCR (P < 0.001). The diagnostic sensitivity of all serological tests, using PCR as the gold standard, was very low, but ELISA and IFAT for anti-Leishmania IgM had 100% specificity. The diagnostic sensitivity of all serological tests could not be improved by changing the cut-off values. Seropositivity for Leishmania spp was not associated with signalment, living conditions, season of sampling and health status of the cats or with seropositivity to feline leukemia virus, feline immunodeficiency virus, feline coronavirus, Toxoplasma gondii and Bartonella henselae. In conclusion, because of their low sensitivity and very high specificity two of the evaluated serological tests (ELISA for anti-Leishmania IgG and IFAT for anti-Leishmania IgM) may be useless as population screening tests but valuable for diagnosing feline infection by L. infantum.
authors.affiliation: Clinic of Medicine, Faculty of Veterinary Science, University of Thessaly, 224 Trikalon Str., GR-43100 Karditsa, Greece. Electronic address: mchatzis@vet.uth.gr.
authors.forename: Manolis K
authors.initials: MK
authors.lastname: Chatzis
authors.affiliation: Laboratory of Epidemiology, Biostatistics and Animal Health Economics, Faculty of Veterinary Science, University of Thessaly, 224 Trikalon Str., GR-43100 Karditsa, Greece.
authors.forename: Leonidas
authors.initials: L
authors.lastname: Leontides
authors.affiliation: Clinic of Medicine, Faculty of Veterinary Science, University of Thessaly, 224 Trikalon Str., GR-43100 Karditsa, Greece.
authors.forename: Labrini V
authors.initials: LV
authors.lastname: Athanasiou
authors.affiliation: Laboratory of Parasitology and Parasitic Diseases, Faculty of Veterinary Sciences, Aristotle University of Thessaloniki, University Campus, GR-54124 Thessaloniki, Greece.
authors.forename: Elias
authors.initials: E
authors.lastname: Papadopoulos
authors.affiliation: Clinic of Medicine, Faculty of Veterinary Science, University of Thessaly, 224 Trikalon Str., GR-43100 Karditsa, Greece.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Kasabalis
authors.affiliation: Companion Animal Clinic (Medicine), Faculty of Veterinary Sciences, Aristotle University of Thessaloniki, 11 Stavrou Voutyra Str., GR-54627 Thessaloniki, Greece.
authors.forename: Mathios
authors.initials: M
authors.lastname: Mylonakis
authors.affiliation: Companion Animal Clinic (Medicine), Faculty of Veterinary Sciences, Aristotle University of Thessaloniki, 11 Stavrou Voutyra Str., GR-54627 Thessaloniki, Greece.
authors.forename: Timoleon
authors.initials: T
authors.lastname: Rallis
authors.affiliation: Quality Veterinary Practice, 96 Syntagmatos Str. 54, Volos, Greece.
authors.forename: Alexandros F
authors.initials: AF
authors.lastname: Koutinas
authors.affiliation: Department of Anatomy and Physiology of Farm Animals, Faculty of Animal Science and Aquaculture, Agricultural University of Athens, 75 Iera Odos, Votanikos, GR-11855 Athens, Greece.
authors.forename: Margarita
authors.initials: M
authors.lastname: Andreadou
authors.affiliation: Department of Anatomy and Physiology of Farm Animals, Faculty of Animal Science and Aquaculture, Agricultural University of Athens, 75 Iera Odos, Votanikos, GR-11855 Athens, Greece.
authors.forename: John
authors.initials: J
authors.lastname: Ikonomopoulos
authors.affiliation: Clinic of Medicine, Faculty of Veterinary Science, University of Thessaly, 224 Trikalon Str., GR-43100 Karditsa, Greece.
authors.forename: Manolis N
authors.initials: MN
authors.lastname: Saridomichelakis
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D019540:Area Under Curve; D002371:Cat Diseases / Q000175:diagnosis* / Q000469:parasitology; D002415:Cats; D004797:Enzyme-Linked Immunosorbent Assay / Q000592:standards / Q000662:veterinary*; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect / Q000592:standards / Q000662:veterinary*; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D018314:Leishmania infantum / Q000276:immunology*; D007898:Leishmaniasis, Visceral / Q000175:diagnosis / Q000662:veterinary*; D008297:Male; D012372:ROC Curve; D012680:Sensitivity and Specificity
chemical_list: D000913:Antibodies, Protozoan; D007074:Immunoglobulin G; D007075:Immunoglobulin M
keywords: Cat; ELISA; IFAT; IgG; IgM; Leishmania infantum