Abstract: PO0042
The Assessment of Bronchoalveolar Lavage (BAL) Fluid Composition in Critically Ill Patients with and Without COVID-19 and AKI
Session Information
- COVID-19: AKI and Basic Science
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Coronavirus (COVID-19)
- 000 Coronavirus (COVID-19)
Authors
- Seif, Nay, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States
- Wunderink, Richard G., Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States
- Srivastava, Anand, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States
- Kapitsinou, Pinelopi P., Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States
Background
Recent reports identified enrichment of T cells and monocytes in the BAL fluid of patients with COVID-19 pneumonia, in contrast to neutrophilia in patients with non-COVID-19 pneumonia, which suggests a distinct immunopathology. We evaluated whether AKI, an independent risk factor for adverse outcomes, modifies BAL cell composition in critically ill patients.
Methods
We retrospectively analyzed BAL specimens from 710 critically ill patients undergoing evaluation for pneumonia at an academic medical center from 3/2018-11/2020. Kruskal-Wallis tests compared distributions of BAL fluid % cell counts by COVID-19 and AKI status. Multivariable linear regression models tested the associations of COVID-19 status with the BAL fluid % cell counts. We tested for effect modification by AKI status. AKI was defined by the KDIGO criteria.
Results
Mean age was 60±15 years and median baseline serum creatinine was 0.8 [0.6–1.1] mg/dl. COVID-19 was positive in 34.5% and AKI occurred in 42.8% of patients. Figure 1A shows differences in BAL fluid cell composition by COVID-19 and AKI status. Highest % of neutrophils were in COVID-19(-) AKI(-) patients and lowest in COVID-19(+) AKI(-) patients. Macrophages, monocytes, and lymphocytes were highest in COVID-19(+) AKI(-) patients and lowest in COVID-19(-) AKI(-) patients. COVID-19(+) patients had a significantly lower % of neutrophils and a higher % of monocytes and lymphocytes after multivariable adjustment (Figure 1B). Patients who were AKI(+) had decreased % of neutrophils when COVID-19(-), while the opposite effect was noted for COVID-19(+) (P for interaction=0.007).
Conclusion
AKI may differentially modify the cell BAL fluid cell composition among patients with suspected pneumonia based on their COVID-19 status.
Funding
- Private Foundation Support