title: Association of Ehrlichia canis, Hemotropic Mycoplasma spp. and Anaplasma platys and severe anemia in dogs in Thailand.
abstract: Canine tick-borne bacteria; Ehrlichia canis, hemotropic Mycoplasma spp. and Anaplasma spp., are organisms transmitted by Rhipicephalus sanguineus ticks. However, only a few clinical studies evaluating dogs infected with these organisms and anemia condition have been published. In this study, the potential tick-borne bacteria linked to anemia were investigated in eighty-one blood samples selected from anemic dogs using a broad range nested-PCR of the 16S rRNA gene. Positive results were shown in 12/81 blood specimens (14.81%). Nucleotide sequences from the PCR products were analyzed using BLAST and resulted in identification of Ehrlichia canis (8), Candidatus Mycoplasma haematoparvum (1) and Anaplasma platys (3). Two other PCR assays were used to detect and identify the positive results of these pathogens including a specific PCR for Ehrlichia canis (gp36) and a specific nested-PCR for hemoplasma species (16S rRNA) and the phylogenetic analyses of E. canis and canine hemoplasmas were performed using these two loci. These specific PCRs revealed co-infection of E. canis and Mycoplasma haemocanis in two cases. These two male dogs had presented with jaundice, severe hemolytic anemia, severe thrombocytopenia, leukocytosis, mild azotemia and hepatitis. Ehrlichia canis was detected in a significantly greater number of severe anemia cases (PCV<15%) than moderate or mild anemia cases (PCV 16-29%) (P<0.05) and these severe anemia cases were 7-fold more at risk of having E. canis infections (odds ratio: 7.11, p=0.020). However, no statistical differences were detected between E. canis detection and degrees of thrombocytopenia or leukopenia. From the results of this study, we conclude that the severity of anemia is associated with E. canis infections rather than the severity of thrombocytopenia.
authors.affiliation: Faculty of Veterinary Medicine, Kasetsart University, Bangkok, Thailand. Electronic address: gunn_kaew@yahoo.com.
authors.forename: Gunn
authors.initials: G
authors.lastname: Kaewmongkol
authors.affiliation: Faculty of Veterinary Medicine, Kasetsart University, Bangkok, Thailand.
authors.forename: Nicha
authors.initials: N
authors.lastname: Lukkana
authors.affiliation: Faculty of Veterinary Medicine, Kasetsart University, Bangkok, Thailand.
authors.forename: Sarawut
authors.initials: S
authors.lastname: Yangtara
authors.affiliation: Faculty of Veterinary Technology, Kasetsart University, Bangkok, Thailand.
authors.forename: Sarawan
authors.initials: S
authors.lastname: Kaewmongkol
authors.affiliation: Faculty of Veterinary Medicine, Kasetsart University, Bangkok, Thailand.
authors.forename: Naris
authors.initials: N
authors.lastname: Thengchaisri
authors.affiliation: Faculty of Veterinary Medicine, Kasetsart University, Bangkok, Thailand.
authors.forename: Theerapol
authors.initials: T
authors.lastname: Sirinarumitr
authors.affiliation: Faculty of Veterinary Medicine, Kasetsart University, Bangkok, Thailand.
authors.forename: Sathaporn
authors.initials: S
authors.lastname: Jittapalapong
authors.affiliation: Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, Boston, USA.
authors.forename: Stanley G
authors.initials: SG
authors.lastname: Fenwick
mesh_terms: D000709:Anaplasma / Q000235:genetics / Q000302:isolation & purification; D000712:Anaplasmosis / Q000150:complications / Q000453:epidemiology / Q000382:microbiology*; D000740:Anemia / Q000150:complications / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D000818:Animals; D060085:Coinfection / Q000662:veterinary; D004283:Dog Diseases / Q000453:epidemiology / Q000382:microbiology*; D004285:Dogs; D041061:Ehrlichia canis / Q000235:genetics / Q000302:isolation & purification; D016873:Ehrlichiosis / Q000150:complications / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D008297:Male; D009174:Mycoplasma / Q000235:genetics / Q000302:isolation & purification; D009175:Mycoplasma Infections / Q000150:complications / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary; D048508:Rhipicephalus sanguineus / Q000382:microbiology*; D017422:Sequence Analysis, DNA / Q000662:veterinary; D013785:Thailand / Q000453:epidemiology; D013921:Thrombocytopenia / Q000662:veterinary; D017282:Tick-Borne Diseases / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*
keywords: Anaplasma platys; Canine hemoplasmas; Ehrlichia canis; Severe anemia