BackgroundTraditional Oriental medicine is used in many Asian countries and involves herbal medicines, acupuncture, moxibustion, and cupping. We investigated the incidence and causes of hospital-acquired fever (HAF) and the characteristics of febrile inpatients in Oriental medical hospitals (OMHs).MethodsPatients hospitalized in two OMHs of a university medical institute in Seoul, Korea, were retrospectively reviewed from 2006 to 2013. Adult patients with HAF were enrolled.ResultsThere were 560 cases of HAF (5.0%). Infection, non-infection, and unknown cause were noted in 331 cases (59.1%), 109 cases (19.5%), and 120 cases (21.4%) of HAF, respectively. Respiratory tract infection was the most common cause (51.2%) of infectious fever, followed by urinary tract infection. Drug fever due to herbal medicine was the most common cause of non-infectious fever (53.1%), followed by procedure-related fever caused by oriental medical procedures. The infection group had higher white blood cell count (WBC) (10,400/mm3 vs. 7000/mm3, p < 0.001) and more frequent history of antibiotic therapy (29.6% vs. 15.1%, p < 0.001). Multivariate analysis showed that older age (odds ratio (OR) 1.67, 95% confidence interval (C.I.) 1.08–2.56, p = 0.020), history of antibiotic therapy (OR 3.17, C.I. 1.85–5.41, p < 0.001), and WBC > 10,000/mm3 (OR 2.22, C.I. 1.85–3.32, p < 0.001) were associated with infection.ConclusionsCompared to previous studies on HAF in Western medicine, the incidence of HAF in OMHs was not high. However, Oriental medical treatment does play some role in HAF. Fever in patients with history of antibiotic therapy, or high WBC was more likely of infectious origin.