Scrub typhus may cause complications such as pneumonia, meningoencephalitis, liver failure, and renal failure, although most of patients with scrub typhus are treated with appropriate antibiotics. Scrub typhus has varying degree of disease severity, from mild to fatal, therefore, early recognition of the clinical parameters representing the severity of the disease is a very important factor for effective treatment.

We investigated clinical, laboratory results and simple chest X-ray images retrospectively by reviewing the medical records of 212 scrub typhus patients, admitted to Catholic University St. Vincent's Hospital from September 2000 to November 2004.

Patients demographics revealed a mean age of 59.7, (age: 18 to 90), and 145 of the 212 patients were female (68.4%). Cure was achieved in 211 (99.5%) of the 212 patients with the 1-week course of daily 200 mg doses of doxycycline. Fifty-nine (27.8%) of the patients revealed the abnormal findings, such as interstitial, pneumonic infiltrations, or pleural effusions, in the results of simple chest X-ray images, and cure was achieved in 58 (98.3%) of 59 patients. The median time to defervescence was 27.1 h for the group showing abnormal simple chest X-ray findings, 23.3 h for the group showing normal chest X-ray findings. The titers of serum C-reactive protein and adenine deaminase were significantly higher, and initial hemoglobin and serum albumin levels were lower, in the group with abnormal simple chest X-ray findings, compared to the group with normal simple chest X-ray findings.

The 1-week course of daily 200-mg doses of doxycycline was effective for the treatment of scrub typhus. Initial simple chest X-ray findings may be useful in the selection of patients, who might show more favorable laboratory findings.