[Babesiosis in an immunocompromised German patient]

Babesiosis is a tick-borne zoonosis. Human cases of babesiosis occur worldwide but have been mainly described in North America and rarely in Europe. The disease manifestations show a broad clinical spectrum including a malaria-like syndrome. Fulminant and life-threatening infections have been described in the setting of asplenia and/or immunosuppression.

A 63-year-old splenectomized patient had been treated with rituximab because of B cell lymphoma. 4 weeks later, he developed signs of infection, anemia, subicterus, and dark urine. Laboratory investigation revealed hemolytic anemia, hemoglobinuria, and renal insufficiency. Blood smears showed Plasmodium-like intraerythrocytic parasites. He had not been exposed to malaria. He had taken frequent walks in the woods around Lake Constance in the south of Germany, where tick-borne diseases are endemic. Babesiosis was confirmed by polymerase chain reaction (PCR) and the parasite was identified as EU1. Serology was negative. Therapy with clindamycin and quinine induced remission. Following a relapse, retreatment with atovaquone and azithromycin was initiated. After several months, seroconversion occurred and the patient cleared the parasite 8 months after first admission.

Human babesiosis does occur in Germany. Patients with splenectomy and/or immunosuppression and malaria-like symptoms should be evaluated for babesiosis by blood smear and PCR.