Adult-onset Still's Disease Associated with Scrub Typhus

Received: March 26, 2015 Accepted: March 28, 2015 Published online: June 08, 2015 Correspondence: Chung-Il Joung, MD. Department of Internal Medicine, Konyang University Hospital, 302-718 Daejeon, South Korea. Tel: +81 103 076 30 29 e-mail: cij1221@kyuh.ac.kr ©2015 Turkish League Against Rheumatism. All rights reserved. Adult-onset Still’s disease (AOSD) is a rare autoinflammatory disorder with typical features of spiking fever, evanescent rash, and arthritis/ arthralgia. Pathogenesis of AOSD is not well known, and it is hypothesized that environmental triggers may initiate disease in individuals with genetic susceptibility. Anecdotal reports have indicated close temporal relationship between AOSD and various infections, which may suggest infectious triggers for developing AOSD, but rickettsial diseases were rarely reported.1-5 A 51-year-old female patient presented with fever for one month. Three weeks ago, she was diagnosed as scrub typhus with fever, severe myalgia, arthralgia, rash, and eschar in the right arm at another hospital (Figure 1). She was a farmer living in Chungcheong province, a rural area of Korea. After introduction of oral doxycycline, patient felt better subjectively, but fever was relapsed. She was treated with empirical intravenous antibiotics for fever of unknown origin for 10 days. She began to complain of pain in the wrists, knees, and ankles and was transferred to our hospital. Spiking fever of 38.3° Celcius once or twice a day was noted. There was maculopapular rash on upper chest and both lower legs, which was minimally itchy and not evanescent. Painful joints were tender but not swollen. Laboratory findings were as follows; white blood cell: 13,700/μL, hemoglobin: 9.9 g/dL, erythrocyte sedimentation rate: 83 mm/hr, C-reactive protein: 10.3 mg/dL, aspartate aminotransferase: 124 IU/L, alanine aminotransferase: 131 IU/L, ferritin >2000 ng/mL (4.63-204.0), rheumatoid factor 6.9 IU/mL, antinuclear antibody 1:80. Antibodies for viral and rickettsial diseases were negative. Abdominal computed tomography revealed several enlarged lymph nodes around common hepatic artery and hepatoduodenal ligament, and other results for evaluation of fever of unknown origin were negative. Patient had severe sore throat during admission and we diagnosed her as having AOSD by Yamaguchi criteria.