Babesiosis
Background
- Spread by the deer tick (Ixodes scapularis)
- People often unaware they are bitten
- Natural reservior is the white footed mouse
- Endemic in US, Europe, parts of Russia and China
- Babesia Microti is pathogen in US
Symptoms
- Fever, hemolytic anemia, chills, thrombocytopenia, DIC
- More severe disease in immunocompromized patients (HIV, Elderly, Asplenic)
Diagnosis
- Peripheral blood smear
- Shows intracellular parasites
- Maltese Cross sign
- May need large smear as parasitemia can be as low as 1%
- Can often be confused for malaria parasites
- Shows intracellular parasites
Differential Diagnosis
Tick Borne Illnesses
- Babesiosis
- Colorado tick fever
- Ehrlichiosis
- Heartland virus
- Lyme
- Murine typhus
- Rocky mountain spotted fever
- Southern tick-associated rash illness (STARI)
- Tick paralysis
- Tularemia
Management
- 2 drug regimen for 7-10 days
antibiotic and antimalarial therapy should be started immediately after diagnosis to reduce the level of parasitemia. The standard treatment has been a combination of However, this regimen occasionally fails, and patients report frequent side effects, including tinnitus, impaired hearing, and diarrhea.
Consequently, a drug regimen consisting of atovaquone and azithromycin is now first-line treatment for mild-to-moderate disease and has been shown to be effective, especially when clindamycin and quinine fail.
In a prospective nonblinded randomized study, Krause et al found that atovaquone (750 mg every 12 hours) plus azithromycin (500 mg on day 1 and 250 mg/day thereafter) was as effective as clindamycin (600 mg every 8 hours) plus quinine (650 mg every 8 hours) in producing a clinical response and clearing parasitemia.[21] All patients were treated for 7 days. Adverse effects were reported by 15% of the atovaquone-azithromycin group and 72% of the clindamycin-quinine group.
Option 1
- Atovaquone (750mg BID) and Azithromycin (500-1000mg on first day, 250-1000mg on subsequent days)
Option 2
- Clindamycin 600mg PO q8hrs x 7-10 days (or 300-600mg IV q6hrs)
- Give with Quinine 650mg TID
Option 3
- Adults: Clindamycin 300-600 mg IV or IM every 6 hour and PO quinine 650 mg every 6-8 hours for 10 days
- Pediatrics: Clindamycin 20 mg/kg/day for children and 25 mg/kg/day for children for 10 days