Rickettsia parkeri infections diagnosed by eschar biopsy, Virginia, USA.

ABSTRACT

BACKGROUND: Infection with Rickettsia parkeri is an emerging tick-borne illness, often accompanied by fever and an eschar at the site of tick attachment. We present three cases of R. parkeri in Virginia residents. CASE PRESENTATIONS Case 1 presented initially afebrile, failed to seroconvert to rickettsial antigens, and was diagnosed by DNA testing of the eschar. Case 2 presented febrile with eschar, no serologies were performed, and was diagnosed by DNA testing of the eschar. Case 3 presented febrile with eschar, serologies were negative for rickettsial antigens, and was diagnosed by DNA testing of the eschar. CONCLUSION: DNA testing of eschars represents an under-utilized diagnostic test and may aid in cases where the diagnosis is not made clinically.