Quality control in the laboratory diagnosis of tuberculosis.
The study was conducted in 4 hospital laboratories to assess the value of smear re-examination, duplicate smear and culture in quality control in the diagnosis of pulmonary tuberculosis. In each hospital 1 to 3 sputum specimens were collected from each suspect and examined by the Ziehl-Neelsen method. Smears along with corresponding specimens were sent to the reference laboratory for re-examination and examination of fresh duplicate smears and culture. A total of 994 specimens plus 23 known negative and 23 known positive controls were analysed. For each assessment method, both over-diagnosis and underdiagnosis were indicated with under-diagnosis being a more common problem in the four hospital laboratories. The limitations of these assessment methods are presented.
Kinyanjui
M G
MG
Kenya Medical Research Institute, Biomedical Sciences Research Centre.
Githui
W A
WA
Kamunyi
R G
RG
Omwega
M J
MJ
Waiyaki
P G
PG
Muthami
L N
LN
D005069:Evaluation Studies as Topic; D006801:Humans; D007630:Kenya / Q000453:epidemiology; D007755:Laboratories, Hospital / Q000592:standards*; D011786:Quality Control; D012680:Sensitivity and Specificity; D013183:Sputum / Q000382:microbiology*; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology