title: Comparison of LED and conventional fluorescence microscopy for detection of acid-fast bacilli in an area with high tuberculosis incidence.
abstract: The objective of the study is to compare the performance of conventional fluorescence microscopy (CFM) and light-emitting diode (LED) fluorescence microscopy (FM) for detection of acid-fast bacilli (AFB) in clinical samples. We included AFB smears, stained using the auramine O method and blindly examined with both CFM and LED-FM. Culture results were used as reference for evaluating the reliability of the FM. We included 180 culture positive specimens and an equal number of culture negative specimens. Sensitivities for the CFM and LED-FM were 79.4% and 82.2%, respectively. Both microscopes had a high specificity (97.2%). The negative-positive (>1 cross) inter-reader agreement of LED-FM and CFM was excellent. Therefore, detection of scanty AFB was higher with LED-FM. Both microscopes were equivalent with respect to time required to read smears. Although it was not faster than CFM, the higher detection of scanty AFB smears combined with ease of use supports the consideration of LED microscopy by all tuberculosis diagnostic laboratories, as a replacement for conventional fluorescence microscopes.
authors: Laboratory of Microbiology and Immunology, UR12SP34, Teaching Hospital Farhat Hached, Sousse, Tunisia. mnmarzouk@gmail.com
authors: Manel
authors: M
authors: Marzouk
authors: Asma
authors: A
authors: Ferjani
authors: Mohamed
authors: M
authors: Dhaou
authors: Moufida Haj
authors: MH
authors: Ali
authors: Naila
authors: N
authors: Hannachi
authors: Jalel
authors: J
authors: Boukadida
mesh_terms: D016022:Case-Control Studies; D046508:Culture Techniques; D006801:Humans; D015994:Incidence; D008027:Light; D008856:Microscopy, Fluorescence / Q000295:instrumentation / Q000592:standards; D009169:Mycobacterium tuberculosis / Q000254:growth & development*; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology; D014416:Tunisia / Q000453:epidemiology