Case 168. Reference case 168A

　 　 　 　
　 Immunostaining using a 1:500 diluted patient's own serum shows granulated positivity in the macrophages located at the ulcer base (indirect immunoperoxidase). 　
　 　 　 　

　

 　 Infection of Rickettsia or Orientia occurs mainly in the endothelial cells of the capillary vessels.