title: Decontamination of sputum for longer time in sodium hydroxide for isolation of Mycobacterium tuberculosis.
abstract: Decontamination by modified Petroff's method is being practiced in many laboratories carrying out Mycobacterium tuberculosis culture and drug susceptibility testing. The method exposes mycobacteria to 4% sodium hydroxide for 30min. However, laboratories in developing countries with limited resources might be using a type of centrifuge that does not open during power failures and exposes the mycobacteria to alkali for longer periods. Out of 28 smear-positive specimens processed, 85.7%, 85.7% and 60.7% of specimens showed a positive culture after exposure to alkali for 0.5, 1.0 and 72h. Laboratories compelled to expose the mycobacteria for a longer duration of time can still attempt isolation for culture as only a small amount of bacteria are needed for culture positivity.
authors.affiliation: Regional Medical Research Centre, P.O. Eastern Railways Complex, Bhubaneswar 751023, India.
authors.forename: P
authors.initials: P
authors.lastname: Satapathy
authors.affiliation: Regional Medical Research Centre, P.O. Eastern Railways Complex, Bhubaneswar 751023, India.
authors.forename: D
authors.initials: D
authors.lastname: Das
authors.affiliation: Regional Medical Research Centre, P.O. Eastern Railways Complex, Bhubaneswar 751023, India.
authors.forename: B N
authors.initials: BN
authors.lastname: Murmu
authors.affiliation: Regional Medical Research Centre, P.O. Eastern Railways Complex, Bhubaneswar 751023, India. Electronic address: skk@icmr.org.in.
authors.forename: S K
authors.initials: SK
authors.lastname: Kar
keywords: Modified Petroff’s method; Sputum; Tuberculosis