Respiratory Viruses in Mechanically Ventilated Patients

A Pilot Study

Raquel Nazareth; Maria-Jesus Chasqueira; Maria-Lúcia Rodrigues; Carolina Paulino; Catarina Conceição; Lia Lêdo; Úrsula Segura; Madalena Santos; António Messias; Pedro Póvoa; Paulo Paixão


BMC Pulm Med. 2020;20(39) 

In This Article


Patient Decription

A total of 44 patients were included in this study, 20 from the WORI group, and 24 from the WRI group. Baseline patient characteristics and admission diagnoses are summarized in Table 1. The median age was 68.3 years (20–87 years) and 56.3% of the patients were male. APACHE II and SAPS II medium scores were 23.5 (3–49) and 53.4 (12–103), respectively. The medium ICU length of stay was 9.7 days (1–25 days). A total of 17 patients died in the ICU.

Viruses Detected Using Real-time PCR

The viruses detected are depicted on Table 2. In the WORI group, 6 of the 20 patients were positive and in the WRI group 12 of the 24 patients were positive. The Cycle Threshold (Ct) varied between 16.14 and 28.78 on WORI group and between 14.52 and 36.86, on WRI group.

In WORI group, the following viruses were identified: Influenza AH3, HPIV 1/3, RSV, HMPV and HRV. In two samples two viruses were detected simultaneously, Influenza AH3 and HRV in one sample and HMPV and HRV in the other one. Both patients died in the ICU. Influenza viruses AH3, HPIV 1/3 and HRV were present in more than one sample.

In the WRI group were detected: Influenza AH3, RSV, HMPV, HRV, HEV and HBoV. Influenza virus AH3, RSV, HMPV and HRV were each identified in three samples. HBoV was identified in two samples and HEV in only one sample. There were three cases of association of two viruses, HEV and HRV, Influenza AH3 with HMPV and HMPV with HBoV. There were six cases of bacterial co-infection with Staphylococcus aureus (N = 2), Moraxella catarrhalis (N = 2) and Streptococcus pneumoniae (N = 2), detected by the routine microbiological procedure in cases of lower respiratory infection. None of these nine patients with viral or bacterial and viral co-infection died in the ICU.

In WORI group, patients with positive samples (WORI+) were older than patients with negative samples (WORI-) (74.2 vs. 61.6 years). Also, WORI+ patients had higher mean severity scores (APACHE II 25.3 vs. 21.9, SAPS II 59.8 vs. 54.8), lower ICU length of stay (4.8 vs. 12.1 days) and invasive mechanical ventilation days (2.3 vs. 9.5) and higher mortality rate (66.7% vs. 42.9%), (Table 3).

Concerning to WRI group, the mean age was the same (70.7 years) in both subgroups of patients, WRI+ and WRI- (Table 3). The severity scores presented higher values in the subgroup WRI- (APACHE II 27.4 vs. 20.5, SAPS II 56.9 vs. 45). ICU length of stay and invasive mechanical ventilation days were similar in both subgroups (9.1 vs. 10 and 5.2 vs. 5.1, respectively). ICU mortality was lower in the WRI+ subgroup (16.7% vs. 41.7%).

The subgroup WORI+ had higher median age (74.2 vs. 70.7 years) and higher values of severity scores (APACHE II 25.3 vs. 20.5; SAPS II 59.8 vs. 45) than WRI+ but lower ICU length of stay (4.8 vs. 9.1) and mechanical ventilation days (2.3 vs. 5.2). ICU mortality was higher in the WORI+ subgroup than in the WRI+ subgroup (66.7% vs. 16.7%).