Effect of storage of sputum specimens at room temperature on smear and culture results

Laboratory evaluation of a specimen transport medium for downstream molecular processing of sputum samples to detect Mycobacterium tuberculosis

“…The effect of ambient transportation and subsequent delays to laboratory testing on sputum M. tuberculosis bacillary and DNA loads for molecular testing is not known, unlike the documented negative effects of delay on culture yield of sputum specimens (Banda et al, 2000, Paramasivan et al, 1983. However, studies on other pathogens in different clinical specimens have shown a negative effect on molecular testing when kept at ambient temperature for extended periods of time (Hasan et al, 2012, Ingersoll et al, 2008.…”

Decontamination methods for samples preserved in cetylpyridinium chloride and cultured on thin-layer agar

“…1 However, in most countries, samples need to be transported to central laboratories for comprehensive diagnostic services, which can take several days, resulting in increasing sample contamination and loss of mycobacterial viability, with subsequent lower recovery rates. 2 N-acetyl-L-cysteine-sodium hydroxide (NALC-NaOH) is commonly used to reduce contamination in specimens before inoculation on selective media. Alternative decontamination techniques include the Petroff method 3 and cetylpyridinium chloride (CPC), an ammonium compound added to samples during storage or transportation for partial digestion and decontamination.…”

Molecular detection of <I>Mycobacterium tuberculosis</I> from sputum transported in PrimeStore<SUP>®</SUP> from rural settings

“…7 longer specimen transport times contribute to loss in viability and reduced culture sensitivity. 8 PrimeStore w Molecular Transport Medium (PS-MTM; Longhorn Vaccines & Diagnostics, San Antonio, TX, USA) has been demonstrated to inactivate M. tuberculosis and to rapidly stabilize and preserve the DNA from sputum specimens at ambient temperature and above for real-time polymerase chain reaction (PCR). 9,10 This system allows ambient temperature collection, storage, and transport of sputum specimens for molecular testing by real-time PCR at a central laboratory.…”