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Updated: May 14, 2026

A Tuberculosis Molecular Bacterial Load Assay (TB-MBLA)
Published on: April 30, 2020
Front-loaded smear microscopy for the diagnosis of pulmonary TB in Tripoli, Libya
Mohamed Gammo1, Widad Lamaric, Mukhtar Hadida
1Parasitology Department, Al Zawiya University, Zawiya, 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.
Method:
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).
Conclusion:
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.
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