Comparison of two concentrations of NALC-NaOH for decontamination of sputum for mycobacterial culture.
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.
Peres
R L
RL
Núcleo de Doenças Infecciosas, Universidade Federal do Espírito Santo, Vitória, Espirito Santo, Brazil.
Maciel
E L
EL
Morais
C G
CG
Ribeiro
F C K
FC
Vinhas
S A
SA
Pinheiro
C
C
Dietze
R
R
Johnson
J L
JL
Eisenach
K
K
Palaci
M
M
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
D012972:Sodium Hydroxide; D000111:Acetylcysteine