Front-loaded smear microscopy for the diagnosis of pulmonary TB in Tripoli, Libya.
BACKGROUND
Diagnosis of pulmonary TB by conventional smear microscopy requires patient attendance on 2 consecutive days. We investigated whether collecting sputum on-the-spot for smear microscopy on the day the patient presented was as sensitive and specific for diagnosis as the conventional spot-morning-spot scheme.


METHODS
We enrolled 412 adults who presented between January 2009 and October 2010 at the National Centre for TB Control in Tripoli, Libya, with cough of >2 weeks' duration, into a cross-sectional survey collecting four sputum specimens: on-the-spot and Xspot on Day 1; morning and on-the-spot on Day 2.


RESULTS
97 (24%) of 401 culture results were culture positive. Spot-Xspot and spot-morning smear microscopy had, respectively, 65% and 66% sensitivity and 97% and 96% specificity (p > 0.5). Spot-Xspot-morning and Spot-morning-spot smear-microscopy had, respectively, 67% and 66% sensitivity and 96% and 96% specificity (p > 0.5).


CONCLUSIONS
For the diagnosis of pulmonary TB, the sensitivity and specificity of front-loaded (same-day) smear microscopy is similar to that of the standard smear microscopy scheme.
Parasitology Department, Al Zawiya University, Zawiya, Libya.
Mohamed
M
Gammo
Widad
W
Lamaric
Mukhtar
M
Hadida
Aida
A
Abuazza
Nabil A
NA
Askar
Mohammed A
MA
Yassin
Luis E
LE
Cuevas
D000293:Adolescent; D000328:Adult; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008002:Libya; D008297:Male; D008853:Microscopy; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*; D013183:Sputum / Q000382:microbiology*; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*; D055815:Young Adult