title: Incidence, risk factors and clinical outcomes of acute kidney injury associated with scrub typhus: a retrospective study of 510 consecutive patients in South Korea (2001-2013).
abstract: Renal involvement in scrub typhus ranges from simple urinary abnormalities to acute kidney injury (AKI) leading to death. This study evaluated the incidence, predictors and prognosis of AKI associated with scrub typhus according to the RIFLE (risk, injury, failure, loss, end-stage kidney disease) criteria.
  
  
  
  We retrospectively evaluated the medical records of patients diagnosed with scrub typhus from January 2001 to November 2013 in Gyeongsang National University Hospital.
  
  
  
  During the study period, 510 patients were diagnosed with scrub typhus and the incidence of AKI was 35.9%. There were 132 (25.9%) patients at risk, 37 (7.3%) with injury and 14 (2.7%) with failure. In comparison with the non-AKI group, the AKI group was older (73.9 vs 63.4 years, p<0.001) and had more comorbidities such as hypertension, diabetes mellitus and chronic kidney disease (CKD). AKI frequently occurs in hypertensive patients taking angiotensin receptor blockers or ACE inhibitors (p=0.002), and in patients with diabetes with higher glycated haemoglobin levels (p=0.033). Haematuria and proteinuria were more frequent in the AKI group. There was no relationship between the severity of proteinuria and occurrence of AKI. Intensive care unit admission and death were more frequent in the AKI group. The renal function of most patients with AKI recovered without sequelae, except for 1 patient who had underlying CKD. Multivariate analysis showed that age, presence of CKD, serum albumin level and time to hospital presentation after symptom onset were independent predictors of AKI in patients with scrub typhus.
  
  
  
  Our current results suggest that the presence of underlying CKD, older age, lower serum albumin level and time to hospital presentation after symptom onset were important risk factors to determine occurrence of AKI. Whether earlier diagnosis and treatment in patients with the above risk factors reduce the incidence and severity of AKI deserves to be investigated.
authors.affiliation: Department of Internal Medicine, Gyeongsang National University Hospital, Jinju, Korea.
authors.forename: Kyungo
authors.initials: K
authors.lastname: Hwang
authors.affiliation: Department of Internal Medicine, Gyeongsang National University Hospital, Jinju, Korea.
authors.forename: Ha Nee
authors.initials: HN
authors.lastname: Jang
authors.affiliation: Department of Internal Medicine, Gyeongsang National University Hospital, Jinju, Korea.
authors.forename: Tae Won
authors.initials: TW
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Gyeongsang National University Hospital, Jinju, Korea.
authors.forename: Hyun Seop
authors.initials: HS
authors.lastname: Cho
authors.affiliation: Department of Internal Medicine, Changwon Gyeongsang National University Hospital, Changwon, Korea.
authors.forename: Eunjin
authors.initials: E
authors.lastname: Bae
authors.affiliation: Department of Internal Medicine, Gyeongsang National University Hospital, Jinju, Korea.|Department of Internal Medicine, Gyeongsang National University School of Medicine, Jinju, Korea.|Institute of Health Science, Gyeongsang National University, Jinju, Korea.
authors.forename: Se-Ho
authors.initials: SH
authors.lastname: Chang
authors.affiliation: Department of Internal Medicine, Changwon Gyeongsang National University Hospital, Changwon, Korea.|Department of Internal Medicine, Gyeongsang National University School of Medicine, Jinju, Korea.|Institute of Health Science, Gyeongsang National University, Jinju, Korea.
authors.forename: Dong Jun
authors.initials: DJ
authors.lastname: Park
mesh_terms: D058186:Acute Kidney Injury / Q000453:epidemiology / Q000209:etiology*; D000328:Adult; D000367:Age Factors; D000368:Aged; D015897:Comorbidity; D005260:Female; D006760:Hospitalization; D006761:Hospitals; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units; D007668:Kidney / Q000473:pathology / Q000503:physiopathology; D007676:Kidney Failure, Chronic / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D051436:Renal Insufficiency, Chronic / Q000150:complications; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D012612:Scrub Typhus / Q000150:complications* / Q000473:pathology
keywords: Acute Kidney Injury; RIFLE; Scrub typhus