Prevalence and clinical course of upper airway respiratory virus infection in critically ill patients with hematologic malignancies

Background
The clinical significance of upper airway respiratory virus (RV) detection in patients with hematologic malignancies remains unclear. We aimed to investigate the association between upper airway RV detection and prognosis in critically ill patients with hematologic malignancies.

Methods
This retrospective observational study included 331 critically ill patients with hematologic malignancies who presented respiratory symptoms and their nasopharyngeal swab was tested using a multiplex PCR assay between January 2017 and December 2018. A logistic regression model was used to adjust for potential confounding factors in the association between assay positivity and in-hospital mortality.

Results
Among the 331 analyzed patients, RVs were detected in 29.0%. The overall mortality rates in the intensive care unit and hospital were 56.8% and 65.9%, respectively. Positive upper airway RV detection was associated with relapsed hematologic malignancies, higher level of C-reactive protein, and prior use of high dose steroids and anti-cancer chemotherapeutic drugs. Furthermore, it was independently associated with in-hospital mortality (adjusted odds ratio, 2.36; 95% confidence interval, 1.23 to 4.54). Among different RVs, parainfluenza virus was more prevalent among patients who died in the hospital than among those who survived (11.5% vs. 3.5%, P = 0.027).

Conclusions
RV detection in the upper respiratory tract was relatively common in our cohort and was significantly associated with a poor prognosis. Thus, it can be used as a predictor of prognosis. Moreover, RV presence in the upper respiratory tract should be examined in patients who have previously been prescribed with high dose corticosteroids and anti-cancer drugs.