Scrub Typhus: Chest Radiographic and Clinical Findings in 130 Thai Patients
Aphinya Charoensak MD*, Orasa Chawalparit MD*, Chaunpit Suttinont MD**, Kanigar Niwattayakul MD***, Kitti Losuwanaluk MD****, Saowaluk Silpasakorn Cert Med Sc Tech*, Yupin Suputtamongkol MD*
Affiliation : * Faculty of Medicine, Siriraj Hospital, Mahidol University ** Department of Medicine, Maharat Nakhon Ratchasima Hospital, Nakhon Ratchasima *** Department of Medicine, Loei Hospital, Loei **** Banmai Chaiyapod Hospital, Bureerum
Objective : To describe chest radiographic findings and their clinical correlation in patients with scrub typhus
diagnosed in Thailand and to determine abnormalities that assist in the diagnosis of scrub typhus.
Materials and Methods : Between July 2001 and December 2002, 130 patients with scrub typhus admitted to
three hospitals in the northeastern Thailand were studied. Data of clinical presentations and chest radio-
graphic findings, reviewed by two radiologists who were unaware of the final diagnosis, were analyzed.
Results : There were 33 women, 97 men; age range, 11-92 years; median age, 45 years old. Pulmonary symp-
toms occurred in 61.5% of the patients and eschar was found in 33.1%. Hepatic dysfunction occurred in 58.5%
and cardiovascular dysfunction in 33%. Pulmonary involvement was the major presentation in 41.5%. Acute
respiratory distress syndrome developed in 7 patients. Overall 5 patients died. The initial radiography showed
abnormalities in 64.6% of the patients. Common radiographic abnormalities included bilateral reticular
opacities (48.5%), cardiomegaly (28.5%), congestive heart failure (18.5%), air space nodules (13.1%), and
pleural effusion (10.8%). Significant association between chest radiographic abnormalities and hepatic and
cardiovascular dysfunction were documented.
Conclusion : Chest radiography should be included in the initial evaluation of patients with suspected scrub
typhus. Bilateral reticular infiltration, with or without cardiomegaly or congestive heart failure, was the most
frequent radiographic finding of scrub typhus.
Keywords : Scrub typhus, Chest radiography, Acute febrile illness
