GIÁ TRỊ CỦA PHƯƠNG PHÁP NUÔI CẤY DỊCH KHÍ QUẢN QUA ĐƯỜNG MŨI TRONG CHẨN ĐOÁN CĂN NGUYÊN VIÊM PHỔI Ở TRẺ EM TẠI TRUNG TÂM HÔ HẤP - BỆNH VIỆN NHI TRUNG ƯƠNG

Abstract

Objectives: Pneumonia is one of the leading causes of mortality in children under 5 years of age; therefore, accurate identification of the bacterial and viral etiology is crucial in clinical practice. Nasotracheal Aspiration (NTA) is a diagnostic method commonly used to assess lower respiratory tract infections. However, the efficacy and safety of this method in detecting pathogenic bacteria need to be compared with Bronchoalveolar Lavage (BAL) - the gold standard. Our study aims to compare the results of pneumonia etiology identification using NTA and BAL methods in children diagnosed with pneumonia at the Respiratory Center of Vietnam National Children’s Hospital.

Methods: The study involved 68 patients aged 6 months to 5 years diagnosed with pneumonia and indicated for bronchoscopy to obtain bronchoalveolar lavage fluid, treated at the Respiratory Center, Vietnam National Children’s Hospital, from May 1, 2025, to October 31, 2025.

Results: The positive bacterial culture rate was 13.2%, with the positive culture rate of bronchoalveolar lavage specimens being 8,8 %. A comparison of bacterial culture results between NTA and BAL specimens showed a concordance rate of 85.3%. NTA demonstrated low sensitivity (16.7%) and high specificity (92%), low positive predictive value (PPV) (16.7%), and high negative predictive value (NPV) (93.4%), indicating that when NTA is negative, the probability of no bacteria in the BAL is very high. Regarding the safety of NTA: there was no difference in SpO2 before and after NTA (p > 0.05); the median respiratory rate before NTA was 32 (20 - 60) and after was 40 (22 -65) (p < 0.05); the mean heart rate before NTA was 119.4 ± 16.7 and after was 131 ± 16.7 (p<0.05); no serious complications were recorded.

Conclusion: The concordance rate of bacterial culture results between NTA and BAL is very high, reaching 85.3%. Compared to BAL, NTA in this study had low sensitivity (16.7%), high specificity (92%), and a low positive predictive value (PPV) (16.7%), suggesting that when NTA is positive, its ability to accurately reflect lower respiratory tract bacteria is limited. The study indicates that NTA, compared to BAL (considered the gold standard), is not clinically useful in evaluating positive results regarding specific bacterial etiology in the lower respiratory tract. However, the use of NTA in general clinical practice remains very important as negative results are valuable for ruling out lower respiratory tract infections, and NTA is assessed as a safe technique that is less invasive than BAL when applied to young children.