Contaminated Specimens

The majority of specimens submitted for mycobacterial culture consist of organic debris, such as mucin, tissue, serum, and other proteinaceous material that is contaminated with organisms. A typical example of such a specimen is sputum. Laboratories must process these specimens so that contaminating bacteria that can rapidly outgrow mycobacteria are either killed or reduced in numbers, and mycobacteria are released from mucin and/or cells. After decontamination, mycobacteria are concentrated, usually by centrifugation, to enhance their detection by acid-fast stain and culture. Unfortunately, there is not one ideal method for decontaminating and digesting clinical specimens. Although continuously faced with the inherent limitations of various methods, laboratories must strive to maximize the survival and detection of mycobacteria on the one hand, while maximizing the elimination of contaminating organisms on the other. Of note, rapidly growing mycobacteria are especially susceptible to high or prolonged exposure to greater than or equal to 2% NaOH.

Nonsterile

Sterile

Nonsterile

Centrifuge and use sediment

Liquefaction (N-aoetyk-cysteine) i

├čeoo├čtannftiatfon(NaOH)

Was this article helpful?

0 0
Bacterial Vaginosis Facts

Bacterial Vaginosis Facts

This fact sheet is designed to provide you with information on Bacterial Vaginosis. Bacterial vaginosis is an abnormal vaginal condition that is characterized by vaginal discharge and results from an overgrowth of atypical bacteria in the vagina.

Get My Free Ebook


Post a comment