title: Associated factors and clinical implications of serum aminotransferase elevation in scrub typhus.
abstract: OBJECTIVE
  Timely diagnosis and prompt treatment can reduce the complications of scrub typhus. It is thus important to find easy laboratory tests to help in the diagnosis, especially in patients without eschar at initial presentation. Because serum aminotransferase elevation is common in scrub typhus, its associated factors and clinical implications need further investigations.
  
  
  METHODS
  We conducted a retrospective study in Kinmen, Taiwan, to collect clinically suspected scrub typhus patients notified to Taiwan Centers for Disease Control for confirmation during 2005-2010. Scrub typhus was diagnosed and Orientia tsutsugamushi was genotyped by serological or molecular assays. The laboratory data and clinical information were recorded for analysis.
  
  
  RESULTS
  Overall, 344 suspected scrub typhus patients were reported to Taiwan Centers for Disease Control and 288 of them were certified scrub typhus. Scrub typhus patients had significantly more thrombocytopenia, serum aminotransferase elevation (76% vs. 54%, p = 0.001), higher frequency of fever, eschar, and lymphadenopathy, compared with nontyphus patients. Hepatic dysfunction in scrub typhus was associated with older age, longer fever duration, and absence of lymphadenopathy, but seemed to be unrelated to the rickettsial genotypes. Multivariate analysis showed that serum aminotransferase elevation (odds ratio: 3.75; p = 0.003; 95% confidence interval: 1.56-9.01) independently predicted scrub typhus. Furthermore, in suspected scrub typhus patients without eschar, 92% of true typhus patients had serum aminotransferase elevation compared with the nontyphus ones (odds ratio: 6.47; p = 0.028, 95% confidence interval: 1.23-34.11).
  
  
  CONCLUSIONS
  Hepatic dysfunction in scrub typhus patients is associated with older age, longer fever duration, and absence of lymphadenopathy. Serum aminotransferase elevation can aid in the diagnosis of scrub typhus, especially in suspected patients without eschar.
authors.affiliation: Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan; Division of Gastroenterology and Hepatology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Hepatitis Research Center, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Tung-Hung
authors.initials: TH
authors.lastname: Su
authors.affiliation: Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan; Division of Gastroenterology and Hepatology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Hepatitis Research Center, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Chun-Jen
authors.initials: CJ
authors.lastname: Liu
authors.affiliation: Centers for Disease Control, Taipei, Taiwan.
authors.forename: Pei-Yun
authors.initials: PY
authors.lastname: Shu
authors.affiliation: Department of Internal Medicine, Kinmen Hospital, Ministry of Health and Welfare, Executive Yuan, Kinmen, Taiwan.
authors.forename: Yang-Hsien
authors.initials: YH
authors.lastname: Fu
authors.affiliation: Department of Internal Medicine, Kinmen Hospital, Ministry of Health and Welfare, Executive Yuan, Kinmen, Taiwan.
authors.forename: Chi-Hsien
authors.initials: CH
authors.lastname: Chang
authors.affiliation: Hepatitis Research Center, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Ping
authors.initials: P
authors.lastname: Jao
authors.affiliation: Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan; Division of Gastroenterology and Hepatology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Hepatitis Research Center, National Taiwan University Hospital, Taipei, Taiwan. Electronic address: kaojh@ntu.edu.tw.
authors.forename: Jia-Horng
authors.initials: JH
authors.lastname: Kao
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D012285:Orientia tsutsugamushi / Q000235:genetics*; D012189:Retrospective Studies; D012612:Scrub Typhus / Q000097:blood* / Q000175:diagnosis* / Q000382:microbiology; D013624:Taiwan; D013921:Thrombocytopenia; D000637:Transaminases / Q000097:blood*
chemical_list: D000637:Transaminases
keywords: Orientia tsutsugamushi; liver function tests; rickettsia