R. africae infection is symptomatic in less than 50% of cases (41). The clinical course typically comprises an abrupt onset of fever, nausea, headache, and neck myalgia commencing 5 to 10 days after a tick bite (26,32). Most patients develop an inoculation eschar, a painless centimeter-large black crust surrounded by a red halo (Figs. 4 and 5), at the site of the tick bite. In 30% to 50% of the cases. Multiple eschars are seen. A painful regional lymphangitis (28), sometimes with a visible draining lymphangitis, is detected in half of the cases and may be found also in the absence of a frank eschar. Less frequent clinical signs of African tick-bite fever include a vesicular or maculopapular cutaneous rash (38), aphthous stomatitis (28), and arthralgia (3). Routine laboratory tests usually reveal lymphopenia and elevated serum C-reactive protein, whereas elevated serum liver enzymes and thrombocytopenia are seen in less than 40% of patients (42).
FIGURE 4 Inoculation eschar on the back of a 54-year-old Norwegian geologist infected with African tick-bite fever in Tanzania.
The majority of patients with African tick-bite fever develop a mild-to-moderately severe illness that either resolves spontaneously within 10 days or responds promptly to antirick-ettsial treatment (26,32,35,37). Complications are rarely seen but recent case reports have described patients presenting with long-lasting fever (43), reactive arthritis (32,44), subacute cranial or peripheral neuropathy (45), chronic fatigue (45), neuropsychiatry symptoms (36), and myocarditis (46). Interestingly, some of these complications may evolve despite preceding treatment with antirickettsial drugs and are likely to be caused by immunological mechanisms (45). No fatalities have ever been reported in African tick-bite fever.
Was this article helpful?
Did You Know That Herbs and Spices Have Been Used to Treat Rheumatoid Arthritis Successfully for Thousands of Years Do you suffer with rheumatoid arthritis Would you like to know which herbs and spices naturally reduce inflammation and pain 'Treating Rheumatoid Arthritis with Herbs, Spices and Roots' is a short report which shows you where to start.