Results
We prospectively enrolled 19 subjects with severe COVID-19 related
pneumonia who required endotracheal intubation and mechanical
ventilation for acute hypoxemic respiratory failure between Aug 2020 and
March 2021 when the alpha variant was in widespread circulation. One
subject was prospectively enrolled into a separate study in May 2020 and
his BAL sample and plasma samples were available for use in future
studies. All subjects had positive nasopharyngeal SARS-CoV-2 RT-PCR and
two subjects had negative viral RT-PCRs on evaluation of the
bronchoalveolar lavage (BAL). The 18 subjects with positive BAL had a
mean age of 68 years (SD 7.8 years) and were predominantly white
(83.3%) (Table 1 and supplemental Table E1). Males and females were
equally distributed. 33.3% (6 of 20) of subjects were considered
immunocompromised: three were solid organ transplant recipients and
three suffered from rheumatologic conditions. Chronic immunosuppressive
medications in these six subjects included mycophenolic acid,
prednisone, tacrolimus, sirolimus and azathioprine. Subjects underwent
bronchoscopy 3.6 days (SD 3.6 days) after intubation and 13.7 (SD 7.8)
days after development of symptoms (3 subjects in week 1, 7 in week 2, 6
in week 3 and 2 in week 5). All eighteen subjects received
corticosteroids prior to bronchoscopy, 17/18 received remdesivir and
one subject received tocilizumab 8 days prior to the BAL. Mortality was
55.6% with 1.8 average ventilator free days (SD 2.9 days).
Survivors and non-survivors had similar age and immuncompromising
comorbidities. The majority of non-survivors were admitted from outside
hospitals and had a longer duration of intubation.