BACKGROUND AND OBJECTIVE: Etiological diagnosis of community-acquired pneumonia (CAP) is only reached in 30-40% of cases, which frequently requires keeping empirical antibiotic regimens. The new nucleic acid amplification techniques (NAAT) in respiratory samples raise the possibility of improving this clinical practice. Our objective was to analyze TAANs contribution estimating both their costs and benefits. PATIENTS AND METHODS: The admitted CAPs were analyzed, in which, if the conventional diagnostic tests were negative, a NAAT was performed. If positive results was made, we assessed if antimicrobials were modified, a cost estimate, and isolation measures. RESULTS: 64 cases were documented. An etiological diagnosis was made in 65.6%: 10.9% were obtained by conventional techniques and the rest (54.7%) by TAAN. These tests' results led to antimicrobial regimen's modification in 88.9% of cases and isolations in 78.5% CONCLUSIONS: Compared to TAAN's economic cost, it is worth considering its contributions, such as antimicrobials' reduction, ecological pressure, and isolations' indications.