title: Risk factors for extra-pulmonary tuberculosis compared to pulmonary tuberculosis.
abstract: BACKGROUND
  Tuberculosis (TB) continues to be a major global health problem. Extra-pulmonary TB (EPTB) manifests with protean symptoms, and establishing a diagnosis is more difficult than pulmonary TB (PTB).
  
  
  METHODS
  A university-affiliated hospital in southern Taiwan.
  
  
  OBJECTIVE
  To analyse the risk factors for EPTB compared with PTB.
  
  
  METHODS
  This retrospective study compared patients with EPTB and PTB in southern Taiwan by analysing their demographic data and clinical underlying diseases. Risk factors for EPTB were further analysed.
  
  
  RESULTS
  A total of 766 TB patients were enrolled in this study, with 102 (13.3%) EPTB and 664 (86.7%) PTB cases. Of the 766 patients, 3% of PTB patients had EPTB, while 19.6% of EPTB patients also had PTB. The most frequently involved EPTB site was the bone and joints (24.5%). The incidence of EPTB vs. PTB decreased significantly for each decade increase in patient age. Multivariate logistic regression analysis showed that being female, not being diabetic, having end-stage renal disease and not smoking were independent risk factors for EPTB.
  
  
  CONCLUSIONS
  This study defines the risk factors for EPTB compared with PTB. Awareness of these factors is essential for physicians to have a high index of suspicion for accurate and timely diagnosis.
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, E-Da Hospital/I-Shou University, Kaohsiung, Taiwan.
authors.forename: J N
authors.initials: JN
authors.lastname: Lin
authors.forename: C H
authors.initials: CH
authors.lastname: Lai
authors.forename: Y H
authors.initials: YH
authors.lastname: Chen
authors.forename: S S J
authors.initials: SS
authors.lastname: Lee
authors.forename: S S
authors.initials: SS
authors.lastname: Tsai
authors.forename: C K
authors.initials: CK
authors.lastname: Huang
authors.forename: H C
authors.initials: HC
authors.lastname: Chung
authors.forename: S H
authors.initials: SH
authors.lastname: Liang
authors.forename: H H
authors.initials: HH
authors.lastname: Lin
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D013624:Taiwan / Q000453:epidemiology; D014376:Tuberculosis / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology; D055815:Young Adult