title: Improved laboratory safety by decontamination of unstained sputum smears for acid-fast microscopy.
abstract: Tubercle bacilli may survive in unstained heat-fixed sputum smears and may be an infection risk to laboratory staff. We compared the effectiveness of 1% and 5% sodium hypochlorite, 5% phenol, 2% glutaraldehyde, and 3.7% formalin in killing Mycobacterium tuberculosis present in smears prepared from 51 sputum samples. The smears were decontaminated by the tube and slide techniques. Phenol at 5%, glutaraldehyde at 2%, and buffered formalin at 3.7% for 1 min (tube technique) or for 10 min (slide technique) were effective in decontaminating sputum smears and preserved cell morphology and quantitative acid-fast microscopy results.
authors.affiliation: Departamento de Análises Clínicas, Universidade Estadual de Maringá, PR, Brazil. betofla@teracom.com.br
authors.forename: Luiz Roberto Bigão
authors.initials: LR
authors.lastname: Giacomelli
authors.forename: Cesar
authors.initials: C
authors.lastname: Helbel
authors.forename: Roger Leandro Nunes
authors.initials: RL
authors.lastname: Ogassawara
authors.forename: Angela Maria Werneck
authors.initials: AM
authors.lastname: Barreto
authors.forename: Fátima Moreira
authors.initials: FM
authors.lastname: Martins
authors.forename: Celso Luíz
authors.initials: CL
authors.lastname: Cardoso
authors.forename: Clarice Queico Fujimura
authors.initials: CQ
authors.lastname: Leite
mesh_terms: D003666:Decontamination / Q000379:methods*; D006801:Humans; D007753:Laboratories; D008853:Microscopy; D009169:Mycobacterium tuberculosis / Q000187:drug effects*; D012449:Safety; D013048:Specimen Handling; D013183:Sputum / Q000382:microbiology*