title: Smear examination of two specimens for diagnosis of pulmonary tuberculosis in Tiruvallur District, south India.
abstract: METHODS
  A general hospital and three peripheral health institutions (PHI) in Tiruvallur District, south India.
  
  
  OBJECTIVE
  To validate the case detection strategy for diagnosis of pulmonary tuberculosis by smear microscopy of two sputum specimens versus three.
  
  
  METHODS
  In the Revised National Tuberculosis Control Programme (RNTCP), three smears from every symptomatic patient attending the PHI were examined for acid-fast bacilli (AFB) by Ziehl-Neelsen (ZN) microscopy. The data from the Tuberculosis Laboratory Registers from the above centres were analysed.
  
  
  RESULTS
  Of 7843 chest symptomatics who had provided three sputum specimens for examination, 895 (11.4%) were smear-positive on at least two specimens. Examination of two specimens--first spot and early morning specimens (837, 93.5%) or early morning and second spot specimens (843, 94.2%)--yielded the highest number of cases.
  
  
  CONCLUSIONS
  The examination of two sputum smears (one spot and an early morning) is as effective as examination of three smears.
authors.affiliation: Tuberculosis Research Centre, Chetput, Chennai, India.
authors.forename: P G
authors.initials: PG
authors.lastname: Gopi
authors.forename: R
authors.initials: R
authors.lastname: Subramani
authors.forename: N
authors.initials: N
authors.lastname: Selvakumar
authors.forename: T
authors.initials: T
authors.lastname: Santha
authors.forename: S I
authors.initials: SI
authors.lastname: Eusuff
authors.forename: P R
authors.initials: PR
authors.lastname: Narayanan
mesh_terms: D006801:Humans; D007194:India; D008853:Microscopy; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013048:Specimen Handling; D013183:Sputum / Q000166:cytology*; D013997:Time Factors; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*