Tsutsugamushi disease caused by Shimokoshi-type Orientia tsutsugamushi: the first report in Western Japan

Abstract

An 85-year-old female farmer was admitted to our hospital for fever, general fatigue, and skin rash. Cephalosporin was not effective and minocycline was dramatically effective. An eschar was discovered on her inguinal region after the defervescence. Laboratory examination of serum taken 12 days after onset of the illness showed elevated titers of antibodies against the Shimokoshi strain of Orientia tsutsugamushi. The gene sequence analysis of specimen from the patient's eschar revealed high similarity to the Shimokoshi strain by nested polymerase chain reaction. Therefore, this patient was diagnosed as a case of Shimokoshi-type tsutsugamushi disease, which has not previously been reported in Western Japan. Recently, cases of this type have also been confirmed in northeastern Japan, suggesting the need for further epidemiological studies.

Figure 1.

(A) Skin rash and (B) eschar at left inguinal region.

Figure 2.

(A and B) The geographic location where the patient was infected.

Figure 3.

Orientia tsutsugamushi genome detection using nested polymerase chain reaction. Pat = patient's skin eschar; Neg = negative control; Shi = Shimokoshi strain (positive control); Kt = Kato strain; M = marker (100 bp ladder).