PT - JOURNAL ARTICLE AU - Nwofor Alfred AU - Lawson Lovette AU - Gambo Aliyu AU - Obasanya Olusegun AU - Panwal Meshak AU - Tunkat Jilang AU - Mosunmola Iwakun AU - Emenyonu Nnamdi AU - Onuoha Olubunmi AU - Patrick Dakum AU - Alash'le Abimiku TI - Optimising <em>Mycobacterium tuberculosis</em> detection in resource limited settings AID - 10.1136/bmjopen-2013-004093 DP - 2014 Mar 01 TA - BMJ Open PG - e004093 VI - 4 IP - 3 4099 - http://bmjopen.bmj.com/content/4/3/e004093.short 4100 - http://bmjopen.bmj.com/content/4/3/e004093.full SO - BMJ Open2014 Mar 01; 4 AB - Objectives The light-emitting diode (LED) fluorescence microscopy has made acid-fast bacilli (AFB) detection faster and efficient although its optimal performance in resource-limited settings is still being studied. We assessed the optimal performances of light and fluorescence microscopy in routine conditions of a resource-limited setting and evaluated the digestion time for sputum samples for maximum yield of positive cultures. Design Cross-sectional study. Setting Facility-based involving samples of routine patients receiving tuberculosis treatment and care from the main tuberculosis case referral centre in northern Nigeria. Participants The study included 450 sputum samples from 150 new patients with clinical diagnosis of pulmonary tuberculosis. Methods The 450 samples were pooled into 150 specimens, examined independently with mercury vapour lamp (FM), LED CysCope (CY) and Primo Star iLED (PiLED) fluorescence microscopies, and with the Ziehl-Neelsen (ZN) microscopy to assess the performance of each technique compared with liquid culture. The cultured specimens were decontaminated with BD Mycoprep (4% NaOH–1% NLAC and 2.9% sodium citrate) for 10, 15 and 20 min before incubation in Mycobacterium growth incubator tube (MGIT) system and growth examined for acid-fast bacilli (AFB). Results Of the 150 specimens examined by direct microscopy: 44 (29%), 60 (40%), 49 (33%) and 64 (43%) were AFB positive by ZN, FM, CY and iLED microscopy, respectively. Digestion of sputum samples for 10, 15 and 20 min yielded mycobacterial growth in 72 (48%), 81 (54%) and 68 (45%) of the digested samples, respectively, after incubation in the MGIT system. Conclusions In routine laboratory conditions of a resource-limited setting, our study has demonstrated the superiority of fluorescence microscopy over the conventional ZN technique. Digestion of sputum samples for 15 min yielded more positive cultures.