NAA tests are more sensitive than smear microscopy and have shorter turnaround time than mycobacterial cultures 7. When used as an initial diagnostic test replacing smear microscopy, the sensitivity of Xpert was 98% for smear-positive pulmonary TB and 68% for smear-negative pulmonary TB, with a specificity of 99% for both 5, 6. Xpert MTB/RIF (Xpert) is a widely used NAA tests for diagnosis of TB and detection of rifampicin resistance. Nucleic acid amplification (NAA) tests for TB diagnosis have been commercially available for more than 20В years. The long turnaround time of mycobacterial cultures limits its application as a rapid diagnostic tool. Traditional microbiological tests for the diagnosis of TB include smear for acid-fast bacilli (AFB) and culture of Mycobacterium tuberculosis (MTB). Delayed diagnosis of TB in critically ill patients may result in death before initiation of anti-TB treatment, which can be as high as 11% to 24% of the mortality cases in Taiwan 3, 4. Rapid diagnosis of TB with early initiation of anti-TB treatment is pivotal in the End TB strategy 2. In 2019, there were an estimated 10 million new TB cases and 1.2 million TB deaths globally 1. Pulmonary tuberculosis (TB) is an airborne transmitted infectious disease associated with high morbidity and mortality. Frontline NAA tests perform better than add-on NAA and no NAA in avoiding treatment delay in all cases, and misdiagnosis of PTB in smear-positive cases. In conclusion, NAA tests help prevent death before treatment initiation. Patients with frontline NAA compared to those with add-on NAA and those without NAA, had a shorter interval between sputum examination and treatment initiation in all cases (3В days vs. Patients with NAA tests had a lower death rate before treatment initiation compared to those without NAA tests (1.6% vs. A total of 2192 PTB patients were enrolled, including 282 with frontline NAA, 717 with add-on NAA, and 1193 with no NAA tests. The outcomes of interest were the proportion of PTB case died before anti-TB treatment, the interval between sputum examination and initiation of treatment, and misdiagnosis of PTB.

PTB patients were classified into a frontline NAA group, an add-on NAA group, and a no NAA group. The clinical impact of nucleic acid amplification (NAA) tests on reducing delayed diagnosis and misdiagnosis of pulmonary TB (PTB) has rarely been investigated.

7 days to die acid