title: Multicentre evaluation of Ziehl-Neelsen and light-emitting diode fluorescence microscopy in China.
abstract: OBJECTIVE
  To assess the feasibility of using light-emitting diode fluorescence microscopy (LED-FM) in peripheral laboratories in China.
  
  
  METHODS
  The performance of LED-FM and Ziehl-Neelsen (ZN) microscopy was compared on slides directly prepared from the sputum of tuberculosis (TB)  suspects and follow-up patients on treatment. The examination time, fading of fluorescence-stained slides, average unit cost and qualitative user appraisal of LED-FM were also analysed.
  
  
  RESULTS
  Among 11 276 slides, the smear-positive rate for LED-FM was 11.2% (1263/11 276),  2.6% (294/11 276) higher than that of ZN (8.6%, 969/11 276; χ(2) 263.5, P < 0.05). The examination time for LED-FM (120.0 ± 38.9 seconds) was shorter than that for ZN (206.3 ± 75.9 s; t = 28.12, P < 0.05). For smear fading,  quantitative and qualitative errors occurred within respectively 7.8 and 7.7 weeks. The average unit costs for ZN and LED-FM were respectively US$2.20 ± 0.58 and US$1.97 ± 0.71 (t = 5.08, P < 0.05). LED-FM was accepted by most laboratory technicians.
  
  
  CONCLUSIONS
  LED-FM compared favourably with ZN, with a higher smear-positive detection rate, a shorter examination time and lower unit examination cost. LED-FM may be an alternative to ZN as a cost-effective method for detecting bacilli in peripheral laboratories in China.
authors.affiliation: National Tuberculosis Reference Laboratory, National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China.
authors.forename: H
authors.initials: H
authors.lastname: Xia
authors.forename: Y-Y
authors.initials: YY
authors.lastname: Song
authors.forename: B
authors.initials: B
authors.lastname: Zhao
authors.forename: K-M
authors.initials: KM
authors.lastname: Kam
authors.forename: R J
authors.initials: RJ
authors.lastname: O'Brien
authors.forename: Z-Y
authors.initials: ZY
authors.lastname: Zhang
authors.forename: H
authors.initials: H
authors.lastname: Sohn
authors.forename: W
authors.initials: W
authors.lastname: Wang
authors.forename: Y-L
authors.initials: YL
authors.lastname: Zhao
mesh_terms: D002681:China; D019411:Clinical Laboratory Techniques; D005240:Feasibility Studies; D006801:Humans; D008856:Microscopy, Fluorescence; D013183:Sputum / Q000382:microbiology; D013194:Staining and Labeling; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000382:microbiology