Canine Granulocytic Anaplasmosis: A Review

Abstract

Anaplasma phagocytophilum is an emerging pathogen of humans, horses, and dogs worldwide that is transmitted by Ixodid ticks and maintained in a variety of small wild mammal species. Recent studies suggest that multiple strains of A. phagocytophilum may be circulating in wild and domestic animal populations, and these strains may have differential host tropisms and pathogenicity. The organism infects and survives within neutrophils by disabling key neutrophil functions, including neutrophil motility, phagocytosis, the oxidative burst mechanism, and neutrophil‐endothelial cell interactions, as well as interfering with neutrophil apoptosis. Coinfections with other tick‐borne pathogens may occur, especially Borrelia burgdorferi. A. phagocytophilum causes an acute febrile illness in dogs with lethargy and inappetence. Less frequent signs include lameness, coughing, polydipsia, intermittent vomiting, and hemorrhages. Diagnosis is based on finding morulae within granulocytes in the peripheral blood, the combination of acute and convalescent serology using immunofluorescent antibody techniques, and detection of the DNA of A. phagocytophilum using specific polymerase chain reaction assays. Whether persistent infection or reinfection with A. phagocytophilum occurs after natural infection requires additional study, with most reports suggesting that anaplasmosis is a self‐limiting disease in dogs that responds well to a 2‐week course of doxycycline therapy.

Türkiye’nin Trakya Bölgesindeki Küçük Ruminantlarda Görülen Anaplasma Türlerinin Moleküler Yöntemlerle Tespiti ve Tiplendirmesi

“…Anaplasma phagocytophilum is the causative agent of tick borne fever in ruminants and granulocytic anaplasmosis in humans, equines and canines [1,14] . A. phagocytophilum can cause subclinical or severe infection in sheep and it is seldom fatal unless complicated by other infections.…”

Ultrasonographic changes in dogs naturally infected with tick borne intracellular diseases

“…The main target organs of tick borne intracellular diseases are bone marrow, spleen and lymph nodes and also affect other internal organs such as the liver, kidney, and lungs (Jacobson and Clark 1994). Multiorgan dysfunction with liver and spleen involvement is common in clinical cases of canine monocytic ehrlichiosis (Ganguly and Mukhopadhayay 2008), babesiosis (Mylonakis et al 2010), anaplasmosis (Carrade et al 2009) and H. canis infection (Baneth 2006). Ultrasonographic changes of liver and spleen in tick borne intracellular haemoparasitic diseases can be used as further diagnostic help apart from other diagnostic procedure.…”

Important frequency of Anaplasma phagocytophilum infection in a population of domiciled dogs in an urbanized area in south-eastern Brazil

“…phagocytophilum antibodies was high, none of the animals exhibited clinical signs of anaplasmosis. It is possible that cross-reaction between species of Anaplasmataceae, rather than exposure to A. phagocytophilum, was responsible for the positive serology (Carrade et al 2009). Moreover, although canine granulocytic anaplasmosis is a self-limiting infection, the antibodies can be detected by IFA for various months (Egenvall et al 1997).…”

“…HGA are widespread in North America, Europe and Asia (Ohashi et al 2005, Teglas & Foley 2006, Zhang et al 2013. Serology is used mainly for screening, but the specificity of the method is low and cross--reactions with other members of the family Anaplasmataceae (mainly A. platys) have been reported (Carrade et al 2009). Molecular methods are very specific, particularly when the tests include nucleotide sequencing (Ebani et al 2013).…”