What precautions are needed to reduce false positive sputum smear results?
Ans: Rinse mouth before sputum collection or collect specimen before food. Use separate wooden stick for each smear preparation and stain each slide separately on a rack. Use new slides. Nevertheless, the scratches on the slide can be differentiated as these occur in parallel rows and are found deeper. Use fresh stains and preferably filter the stains before use. Preferably, use distilled water to avoid false positive result from environmental mycobacteria. Do not touch the slide with the objective of the microscope or the oil dropper. Clean lens with a lens cleaning paper (not cotton) after exam of each slide.
