Most infections are probably asymptomatic, as indicated by serologic surveys.
Manifestations of disease include fever, chills, sweating, myalgias, fatigue, hepatosplenomegaly, and hemolytic anemia.
Symptoms typically occur after an incubation period of 1 to 4 weeks, and can last several weeks.
The disease is more severe in patients who are immunosuppressed, splenectomized, and/or elderly.
Infections caused by B. divergens tend to be more severe (frequently fatal if not appropriately treated) than those due to
B. microti, where clinical recovery usually occurs.
Diagnosis can be made by
microscopic examination of thick and thin blood smears stained with Giemsa.
Repeated smears may be needed.
the organisms by inoculation of patient blood into hamsters or gerbils may also assist in
diagnosis. Animals inoculated with infective blood typically develop parasitemia within
1 to 4 weeks.
clindamycin* plus quinine or atovaquone* plus azithromycin* are the options.
The Medical Letter notes that exchange transfusion has been used in severely
ill patients with high parasitemias.
* These drugs are approved by the FDA, but considered investigational for this purpose.