Review of Nucleic Acid Amplification Tests and Clinical Prediction Rules for Diagnosis of Tuberculosis in Acute Care Facilities

Abstract

Tuberculosis (TB) remains an important cause of hospitalization and mortality in the United States. Prevention of TB transmission in acute care facilities relies on prompt identification and implementation of airborne isolation, rapid diagnosis, and treatment of presumptive pulmonary TB patients. In areas with low TB burden, this strategy may result in inefficient utilization of airborne infection isolation rooms (AIIRs). We reviewed TB epidemiology and diagnostic approaches to inform optimal TB detection in low-burden settings. Published clinical prediction rules for individual studies have a sensitivity ranging from 81% to 100% and specificity ranging from 14% to 63% for detection of culture-positive pulmonary TB patients admitted to acute care facilities. Nucleic acid amplification tests (NAATs) have a specificity of >98%, and the sensitivity of NAATs varies by acid-fast bacilli sputum smear status (positive smear, ≥95%; negative smear, 50%-70%). We propose an infection prevention strategy using a clinical prediction rule to identify patients who warrant diagnostic evaluation for TB in an AIIR with an NAAT. Future studies are needed to evaluate whether use of clinical prediction rules and NAATs results in optimized utilization of AIIRs and improved detection and treatment of presumptive pulmonary TB patients.

Head-to-head comparison of the diagnostic value of five tests for constrictive tuberculous pericarditis

“…Nucleic acid amplification tests (NAATs) are a significant advance in the diagnosis of TB and can detect MTB DNA or RNA, which can provide microbiological evidence ( Chitnis et al, 2015 ). The Xpert MTB/RIF assay (Cepheid, Sunnyvale, CA, USA) is one of the most widely used NAATs for diagnosing TB and shows good diagnostic performance for both PTB and EPTB; its test results can be obtained within 2 hours to meet the need for rapid diagnosis .…”

Clinical Impact of Nucleic Acid Amplification Testing in the Diagnosis of Mycobacterium Tuberculosis: A 10-Year Longitudinal Study

“…In areas with low TB prevalence, isolating all patients with pulmonary symptoms and chest radiograph suspicious for TB leads to overuse of airborne isolation rooms [14, 15]. Similarly, solely using an AFB smear-positive result to determine the need for airborne isolation may be unreliable given the increasing incidence of NTM [16].…”

Use of Nucleic Acid Amplification Tests in Tuberculosis Patients in California, 2010–2013

“…Our study was not able to assess whether 2 NAATs would reduce the percentage of negatives. A recently proposed infection prevention strategy that combines clinical prediction rules to detect patients at high risk for culture-positive pulmonary TB and NAATs for TB detection would be a more conservative approach that may prevent inappropriate release from AII [14]. …”