Conversation: The conversation between human and AI assistant.
[|Human|] hello,i waana ask abt my father...actually his skin test for tb infection came negative,then sputum test too was negative,after bronchoscopy doctor went for sputum culture ,there in the 6th week they fond the tb bacteria...although my father is absolutely fine ..no cough ,no sputum problem could u pls tell me that how much the report is reliable
[|AI|]  Hello, I understand the confusion that this situation can create, although it is not uncommon in TB. A skin test cannot reliably diagnose an active TB infection and thus a negative test does not rule out tuberculosis. Sputum can often diagnose tuberculosis, but when sputum samples are insufficient, bronchoscopic samples may be collected by a physician. These samples are far more accurate and reliable than simple sputum samples. A positive culture for TB from a bronchoscopic sample is very reliable and indicates infection with tuberculosis. The only important caveat is that the TB culture can sometimes pick up other bacteria as well. The "AFB" (Acid fast bacilli) culture can start growing bacteria that look like TB but are different bacteria (nontuberculous Mycobacteria). You should ask the doctor if the result so far is positive for Acid Fast Bacilli or for Tuberculosis. It takes a bit of time to be able to identify the organism is true TB after the initial detection of Acid Fast Bacilli. I hope this clears things up a little.