An immunocompromised patient presented with febrile episodes, an erysipelas-like rash, and thromboembolic complications. Amplification of 16S rRNA gene sequences from blood and sequence analysis revealed "Candidatus Neoehrlichia mikurensis." We report the first case of human disease caused by "Ca. Neoehrlichia mikurensis."
CASE REPORTA 77-year-old man with B-cell chronic lymphocytic leukemia developed autoimmune anemia in 2007 and started long-term treatment with corticosteroids. In September of the same year, he had a transitory ischemic attack. Since his hemolytic anemia worsened despite treatment with corticosteroids, he was given courses of cyclophosphamide during the second half of 2008. The patient developed autoimmune thrombocytopenia (platelet count, 38 ϫ 10 9 /liter; reference range for healthy adults, 145 ϫ 10 9 to 355 ϫ 10 9 /liter) and was splenectomized laparoscopically on 4 June 2009, with subsequent normalization of platelet counts.While kayaking on 3 July 2009, the patient developed acute diarrhea, which was followed by fever and chills and a short episode of loss of consciousness the same night. When admitted to Kungälv Hospital, Kungälv, Sweden, the next day under suspicion of sepsis, he was hypotensive (blood pressure [BP], 85/60 mm Hg) and febrile (temperature, 38.5°C; reference, Ͻ38.0°C). Deep vein thrombosis in the left lower extremity encompassing the groin and pulmonary embolism were also discovered. The patient was treated intravenously (i.v.) with ceftazidime for 1 week, but no microbe was identified. The patient's systemic inflammatory reaction (C-reactive protein level of 92 mg/liter [reference, Ͻ5 mg/liter] and fever) was judged to result from widespread thromboembolism, and the patient was discharged on 10 July with low-molecular-weight heparin medication.A month later, the patient was readmitted to Sahlgrenska University hospital with a fever of 39.5°C, BP of 105/55 mm Hg, and an erysipelas-like rash on the inside of the left leg. The patient was anemic (hemoglobin [Hb], 85 g/liter; reference range, 134 to 170 g/liter) and had leukocytosis (white blood cell [WBC] count, 11 ϫ 10 9 /liter; reference range, 3.5 ϫ 10 9 to 8.8 ϫ 10 9 /liter) with a pronounced left shift, a normal platelet count, and a C-reactive protein level of 54 mg/liter (reference, Ͻ5 mg/liter). Hyponatremia was present (sodium level, 134 mmol/liter; reference range, 137 to 145 mmol/liter). The patient was taking warfarin, oral prednisolone, omeprazole, and vitamin B tablets. He was treated with i.v. cloxacillin for 2 days, followed by oral floxacillin (flucloxacillin) for 2 days and, finally, i.v. meropenem for 7 days (Fig. 1). Fever, elevated levels of C-reactive protein, and hyponatremia resolved within 1 week, apparently after the institution of meropenem (Fig. 1). All cultures (three blood cultures, two urinary cultures, and one oral swab culture) were negative. A chest X ray revealed scant infiltrates around the hili and in the basal part of the right lung, but computed tomography (CT) scans of the thorax and ...