Can A Rapid TB Sputum Test Replace The Traditional Weeks Long Sputum Culture ?

Posted on Mon, 16 Jul 2012

Question: Can a rapid TB sputum test replace the traditional weeks long sputum culture? I'm going through the us immigration process. I had a positive TB skin test, got a csx which showed several tiny granuloma, the doc sent me to the TB clinic to get meds and get them to sign off. They wouldn't do this because any irregularity automatically puts me in class b and requires a sputum culture which I'm told takes 8 to 12 weeks. I don't have that kind of time! I told them I'd have the radiologist pull the film to confirm calcification but he couldn't without a CT. So I got a CT. It didn't say anything about calcification. Now it seems my only option is to get these cultures? Is there any other way? A quicker way? All I need is for the TB clinic to sign off so I can send off my paperwork to immigration.

Answered by Dr. Aparna Kohli (5 hours later)

Hi,
Thanks for writing in.
A rapid TB sputum test cannot replace the culture, which usually takes 6-8 weeks to report. Culture remains the gold standard for diagnosis. The only way out I believe is to get a polymerase chain reaction test (PCR) for Acid fast bacilli (AFB). The results are usually available on the same or the next day. However, I would suggest that you contact your physicians whether a negative PCR would serve the purpose of getting you through immigration.
Hope this helps. Let me know if I can address any more concerns.
Regards

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar