Two Cases of Cellulitis in the Course of African Tick Bite Fever: A Fortuitous Association?

In African tick bite fever (ATBF), inoculation eschar – resulting from disruption of the cutaneous barrier – may be a risk factor for cellulitis. We report 2 cases of ATBF associated with cellulitis. A 77-year-old woman was referred for severe leg cellulitis upon returning from sub-Saharan Africa. She developed erythematous macules. Rickettsia africae was detected by PCR assay from a skin biopsy specimen, and ATBF diagnosis was confirmed. A 75-year-old man was hospitalized after his return from Zimbabwe for a maculopapular exanthema and erysipelas-like rash of the leg. The diagnosis of cellulitis associated with ATBF was confirmed by PCR and serological methods. Both patients were treated for ATBF and cellulitis by a combination of doxycycline and β-lactam antibiotics, and both had a good recovery. Inoculation eschar may be a risk factor for cellulitis; thus, we hypothesize a non-fortuitous association between ATBF and cellulitis.