Concentrated specimen smear microscopy utilising a polymer membrane sandwich filtration vessel for the detection of acid-fast bacilli in health facilities in Sabah, East Malaysia. (March 2022)

• Record Type: Journal Article
• Authors: Paul, Dawn Carmel; Ngeow, Yun Fong; Yap, Sook Fan; Dony, Jiloris F.; Avoi, Richard; Mohammad, Rashidah; Ng, Hien Fuh
• Is Part Of: Tuberculosis. Volume 133(2022)
• Publication Date: 2022-03
• Subjects: Acid fast bacilli -- Microscopy -- PVDF -- SFV-CSSM -- Sandwich filtration vessel; 616.995
• DOI: 10.1016/j.tube.2022.102183
• Languages: English
• ISSNs: 1472-9792

Abstract

Abstract: A simple, ready-to-use concentrated specimen smear microscopy method employing a nanometer silicon polyvinylidene fluoride (PVDF) polymer membrane sandwich filtration vessel to concentrate acid-fast bacilli (AFB) in samples (SFV-CSSM, Hunan-Tech New Medical System Co. Ltd. China) was compared with direct sputum smear microscopy (DSSM) to determine its performance using culture on modified Ogawa agar as reference. The results for 4114 clinical samples collected from health facilities in Sabah were interpreted with reference to culture results, sample collection-transportation conditions and clinical data including responses to anti -TB drug treatment. The SFV-CSSM showed higher sensitivity than DSSM (79.4% versus 60.5%) and less background interference. Its ability to detect low levels of AFB at an affordable cost makes it an excellent tool for the screening of pauci-bacillary samples as well as for active case finding in TB control programs. Highlights: The SFV-CSSM, a membrane-filtration concentration method showed increased sensitivity when compared to DSSM for AFB detection. SFV-CSSM grading was found to be 2 to 3 times higher than the DSSM grading. SFV-CSSM is a potentially better microscopy method for early detection of TB and diagnosis of extra-pulmonary TB cases.