title: Think TB! Is the diagnosis of pulmonary tuberculosis delayed by the use of antibiotics?
abstract: METHODS
  Effective tuberculosis (TB) control requires prompt diagnosis of infectious cases through early suspicion of pulmonary TB in all subjects with suspected respiratory infection.
  
  
  OBJECTIVE
  To test our hypothesis that prior antibiotic treatment for presumed bacterial infection leads to a delay in diagnosing TB in a European country with low TB incidence.
  
  
  METHODS
  Adults with culture-confirmed pulmonary TB at a single metropolitan centre were assessed for the impact of any previous antibiotic treatment on symptoms and the time to starting specific anti-tuberculosis treatment.
  
  
  RESULTS
  Of 83 patients, 42 (51%) received antibiotics prior to TB diagnosis, with symptomatic improvement reported in 20 of the 42 (48%) patients. This was unrelated to specific drug class. Although the median time to diagnosis in subjects receiving antibiotics was prolonged (P=0.001), this was not predicted by treatment response. In 94% of cases, the initial chest radiograph was suggestive of TB infection.
  
  
  CONCLUSIONS
  Patients receiving antibiotics prior to TB confirmation experience a process-related delay in starting treatment. To minimise the risk of ongoing TB transmission, we propose that clinicians should include TB in their differential diagnosis and initiate simple, TB-focused investigations early on in the diagnostic process.
authors.affiliation: Department of Respiratory Medicine, Royal Free Hospital, and Department of Medical Statistics and Epidemiology, Royal Free & University College Medical School, London, UK. sonya.craig@orh.nhs.uk
authors.forename: S E
authors.initials: SE
authors.lastname: Craig
authors.forename: H
authors.initials: H
authors.lastname: Bettinson
authors.forename: C A
authors.initials: CA
authors.lastname: Sabin
authors.forename: S H
authors.initials: SH
authors.lastname: Gillespie
authors.forename: M C I
authors.initials: MC
authors.lastname: Lipman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D017714:Community-Acquired Infections / Q000175:diagnosis / Q000188:drug therapy*; D003937:Diagnosis, Differential; D042241:Early Diagnosis; D004632:Emergency Medical Services / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000175:diagnosis / Q000188:drug therapy*; D010818:Practice Patterns, Physicians'; D011320:Primary Health Care / Q000379:methods; D016896:Treatment Outcome; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents