Non-ventilator hospital-acquired pneumonia diagnostic procedures – A systematic review

OBJECTIVES: Non-ventilator hospital-acquired pneumonia (NV-HAP) is an important hospital-acquired infection with high morbidity and mortality. This review aimed to evaluate the effectiveness, acceptability, and accuracy of current diagnostic procedures for NV-HAP. METHODS: The protocol was published in the International Prospective Register of Systematic Reviews under registration CRD42023375750. A comprehensive search of PubMed, The Cochrane Library, CINAHL, EMBASE, Web of Science, and grey literature was conducted using terms related to NV-HAP diagnostics. Eligible studies were appraised using a modified Critical Appraisal Skills Programme checklist for diagnostic studies. RESULTS: Of 26,780 records screened, 317 underwent full-text review and eight met inclusion criteria. Two studies evaluated biomarkers in blood and suggested cut-off points for procalcitonin after receiver operating characteristics analysis. Four studies evaluated sampling methods and showed a superior performance of bronchoalveolar lavage compared to expectorated sputum and endotracheal aspirates. Two studies evaluated molecular diagnostics, presenting higher detection rates and good agreement with conventional culturing methods. Substantial heterogeneity prevented quantitative synthesis. CONCLUSION: NV-HAP remains insufficiently investigated, and available diagnostic evidence is limited and inconsistent. Standardized, validated diagnostic criteria are urgently needed to strengthen future research, enable comparability across studies, and improve diagnostic reliability in clinical practice.