Think TB! Is the diagnosis of pulmonary tuberculosis delayed by the use of antibiotics?
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.
Craig
S E
SE
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
Bettinson
H
H
Sabin
C A
CA
Gillespie
S H
SH
Lipman
M C I
MC
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
D000900:Anti-Bacterial Agents