Human Anaplasmosis and Anaplasma ovis Variant

To the Editor: Anaplasmosis is a disease caused by bacteria of the genus Anaplasma. A. marginale, A. centrale, A. phagocytophilum, A. ovis, A. bovis, and A. platys are obligate intracellular bacteria that infect vertebrate and invertebrate host cells. A. ovis, which is transmitted primarily by Rhipicepha-lus bursa ticks, is an intraerythrocytic rickettsial pathogen of sheep, goats, and wild ruminants (1). Anaplasma spp. infections in humans have been reported in Cyprus (2,3). We report infection of a human with a strain of Anaplasma sp. other than A. phagocytophilum, which was detected by PCR amplifi cation of ana-plasmatic 16S rRNA, major surface protein 4 (msp4), and heat shock protein 60 (groEL) genes. A 27-year-old woman was admitted to the pathology clinic of a hospital in Famagusta, Cyprus on May 14, 2007, with an 11-day history of fever (<39.5°C) after a tick bite. Before admission , the patient was treated with cefi xime (400 mg/d for 3 days) and cefradine (2 g/d for 2 days) without abatement of the fever. Physical examination showed hepatosplenomega-ly and an enlarged lymph node. Initial laboratory examinations showed moderate anemia (hemoglobin 11.5 g/dL), thrombocytopenia (95,000 thrombocytes/mm 3), increased levels of transaminases (aspartate ami-notransferase 178 U/L, alanine ami-notransferase 313 U/L, γ-glutamyl transferase 79 U/L, lactate dehydroge-nase 698 U/L), an increased level of C-reactive protein (10.4 mg/L), and an increased erythrocyte sedimenta-tion rate (80 mm/h). Blood samples were obtained from the patient at the time of admission and 7 days and 3 months later. Results of blood and urine cultures were negative for bacteria. A chest radiograph, computed tomography of the abdomen, and an echocardiograph of the heart showed unremarkable results. Blood samples were negative for antibodies against cytomegalovirus, Epstein-Barr virus, and for rheumatoid factors. A lymph node biopsy specimen was negative for infi ltration and malignancy. After treatment with doxycycline (200 mg/ day for 11 days), ceftriaxone (2 g/day for 5 days), and imipenem/cilastatin (1,500 mg/day for 1 day), the patient recovered and was discharged 17 days after hospitalization. Three serum samples from the patient were tested in Crete, Greece, for immunoglobulin (Ig) G and IgM against A. phagocytophilum antigen by using an immunofl uorescent anti-body assay (Focus Diagnostics, Cypress , CA, USA). Serologic analysis showed IgG titers of 0, 0, and 128 and IgM titers of 20, 20, and 20 against A. phagocytophilum in the 3 serum samples , respectively. Because the blood samples were transported frozen, detection …