title: Clinical and laboratory findings associated with severe scrub typhus.
abstract: BACKGROUND
  Scrub typhus is a mite-borne bacterial infection of humans caused by Orientia tsutsugamushi that causes a generalized vasculitis that may involve the tissues of any organ system. The aim of this study was to identify factors associated to severe complications from scrub typhus.
  
  
  METHODS
  We conducted this prospective, case-control study on scrub typhus patients who presented to the Department of Internal Medicine at Chosun University Hospital between September, 2004 and December, 2006. Cases were 89 scrub typhus patients with severe complications and controls were 119 scrub typhus patients without severe complications.
  
  
  RESULTS
  There were significant differences in the absence of eschar, white blood cell (WBC) counts, hemoglobin, albumin, serum creatinine, fibrinogen, C-reactive protein (CRP), and active partial thromboplastin time (aPTT) between the two groups. Multivariate analysis demonstrated that only the following four factors were significantly associated with the severe complications of scrub typhus: (1) age >or= 60 years (odd ratio [OR] = 3.13, P = 0.002, confidence interval [CI] = 1.53-6.41), (2) the absence of eschar (OR = 6.62, P = 0.03, CI = 1.22-35.8, (3) WBC counts > 10, 000/mm3 (OR = 3.6, P = 0.001, CI = 1.65-7.89), and (4) albumin <or= 3.0 g/dL (OR = 5.01, P = 0.004, CI = 1.69-14.86).
  
  
  CONCLUSIONS
  Our results suggest that clinicians should be aware of the potential for complications, when scrub typhus patients are older (>or= 60 years), presents without eschar, or laboratory findings such as WBC counts > 10, 000/mm3, and serum albumin level <or= 3.0 g/dL. Close observation and intensive care for scrub typhus patients with the potential for complications may prevent serious complications with subsequent reduction in its mortality rate.
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, Chosun University School of Medicine, Gwangju City, Republic of Korea.
authors.forename: Dong-Min
authors.initials: DM
authors.lastname: Kim
authors.forename: Seok Won
authors.initials: SW
authors.lastname: Kim
authors.forename: Seong-Hyung
authors.initials: SH
authors.lastname: Choi
authors.forename: Na Ra
authors.initials: NR
authors.lastname: Yun
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012285:Orientia tsutsugamushi / Q000302:isolation & purification*; D011446:Prospective Studies; D012307:Risk Factors; D012612:Scrub Typhus / Q000150:complications* / Q000453:epidemiology / Q000473:pathology*