Figure 4. Quantification of inflammatory changes in inoculation eschars from patients with African tick-bite fever (Rickettsia africae, n = 8) and patients with Mediterranean spotted fever (R. conorii, n = 15). Surface areas expressing CD15, CD68, CD3, CD20, and Factor VIII were quantified after immunostaining. Quantification of each parameter was evaluated by computer-assisted analysis of digitized microscopic images. Results were normalized and expressed as a percentage of the total skin tissue surface area. Columns represent mean values ± standard error.