title: Comparison of two concentrations of NALC-NaOH for decontamination of sputum for mycobacterial culture.
abstract: This study compared the effect of using two different concentrations of sodium hydroxide (NaOH) in the N-acetyl-L-cysteine-sodium hydroxide (NALC-NaOH) method for sputum decontamination on smear and culture positivity and the proportion of contaminated cultures: 14% of cultures were contaminated using the standard final 1% NaOH concentration during processing compared to 11% contaminated cultures using a final 1.25% NaOH concentration (P < 0.008). The proportion of cultures positive for mycobacteria decreased from 21% to 11% for sputum processed with 1% and 1.25% final NaOH concentrations, respectively (P < 0.001). Our findings suggest that a small reduction in culture contamination did not justify the considerable loss of positive cultures.
authors.affiliation: Núcleo de Doenças Infecciosas, Universidade Federal do Espírito Santo, Vitória, Espirito Santo, Brazil.
authors.forename: R L
authors.initials: RL
authors.lastname: Peres
authors.forename: E L
authors.initials: EL
authors.lastname: Maciel
authors.forename: C G
authors.initials: CG
authors.lastname: Morais
authors.forename: F C K
authors.initials: FC
authors.lastname: Ribeiro
authors.forename: S A
authors.initials: SA
authors.lastname: Vinhas
authors.forename: C
authors.initials: C
authors.lastname: Pinheiro
authors.forename: R
authors.initials: R
authors.lastname: Dietze
authors.forename: J L
authors.initials: JL
authors.lastname: Johnson
authors.forename: K
authors.initials: K
authors.lastname: Eisenach
authors.forename: M
authors.initials: M
authors.lastname: Palaci
mesh_terms: D000111:Acetylcysteine / Q000737:chemistry; D001431:Bacteriological Techniques; D003666:Decontamination / Q000379:methods*; D006801:Humans; D009161:Mycobacterium / Q000302:isolation & purification; D011446:Prospective Studies; D012972:Sodium Hydroxide / Q000737:chemistry*; D013048:Specimen Handling; D013183:Sputum / Q000382:microbiology*; D014376:Tuberculosis / Q000175:diagnosis / Q000382:microbiology
chemical_list: D012972:Sodium Hydroxide; D000111:Acetylcysteine