Scrub Typhus (Tsutsugamushi Disease) Presenting as Fever with an Eschar

A 76-year-old Japanese male farmer presented with a 2-day history of high fever, rash, intense headache, and diffuse myalgias. Physical examination revealed a non-pruritic maculopapular rash on his trunk and extremities (Fig. 1). An eschar was located on his right chest, which indicated the site of an infected chigger bite (Fig. 2). Serological tests revealed 1:160 titers of anti-Orientia tsutsugamushi IgM and a fourfold increase in titers between paired samples. Scrub typhus was diagnosed. After treatment with minocycline (200 mg/day for 14 days), his symptoms resolved completely.

Figure 1

Pink erythematous papules 2–5 mm in diameter are visible on the patient’s trunk.

Figure 2

Infiltrative erythema (diameter, 20 mm) with a black eschar in the center.

Scrub typhus, also known as tsutsugamushi disease, is an acute, potentially lethal infectious disease caused by Orientia tsutsugamushi. Orientia tsutsugamushi is distributed throughout the Asia Pacific area. Most patients present with high-grade fever, intense generalized headache, and diffuse myalgias. Approximately 50 % of patients develop a non-pruritic macular or maculopapular rash. In addition, some patients develop an eschar at the site of the infected chigger bite, which is an important clinical clue for diagnosing scrub typhus, as 60–88 % of patients with scrub typhus exhibit an eschar.1 Therefore, a methodical physical examination of the entire body should be performed to identify eschars in patients who come from an endemic area.