Characteristics of broncoalveolar lavage findings in Post-COVID-19 pneumonia patients with persistent interstitial lung disease: prospective analysis from a dedicated outpatient setting post-hospitalization

V. Clérigo*^a (Dr), L. Fernandes^a (Dr), A. Alfaiate^a (Dr), D. Noivo^a (Dr), P. Duarte^a (Dr)

^a Pulmonology Department, São Bernardo Hospital, Setúbal Hospital Center, Portugal, Setúbal, PORTUGAL

* vclerigo21@gmail.com

Background: Newly diagnosed persistent Post-COVID-19 interstitial lung disease (ILD) data remains largely understudied after hospital discharge in symptomatic patients. We aim to evaluate the characteristics of BAL findings in selected patients.

Methods: We performed a prospective observational study of 433 patients admitted to Pulmonology Post-COVID-19 Consultation (05/2020-04/2022). The diagnosis of newly persistent ILD was performed at least 6 months after acute infection, despite steroid treatment. Twenty-two (5.1%) patients were proposed to bronchofibroscopy (BF) with BAL (Pentax^® EB-10 Scopes).

Results: BF pathologic findings were diagnosed in the majority of the patients (72.7%). Median age was 63.5 years (range: 41 to 78 years) and the majority was male (54.5%). Fatigue and dyspnoea were the most common complaints. Bronchial mucosal inflammation was present in the majority of cases (54.5%). BAL had a predominant cellular pattern in 6 cases (27.3%): lymphocytic (3; 13.6%) and neutrophilic (3; 13.6%). One case of lipid-laden alveolar macrophages was identified. BAL microbiological analysis revealed at least one pathogen in 3 cases (13.6%). There was no correlation between clinical symptoms, previous COVID-19 severity and BAL cellular pattern. Overall, BAL had an impact on medical decision-making in all cases: proposal to ILD Multidisciplinary Reunion to discuss ILD diagnosis (9; 40.9%); introduction of immunosuppression or antimicrobial therapy (4; 18.2%); surveillance/respiratory comorbid diagnosis (6; 27.2%); and clinical discharge (3; 13.6%).

Conclusion: Our real-life data results support the implementation of a Pulmonology Post-COVID-19 Consultation that includes use of BAL as a diagnostic complementary tool in selected patients. BAL had a nonegligible diagnostic yield and impact on medical decisions. A possible high rate of undiagnosed Post-COVID-19 ILD may be an explanation for the persistent symptomatic burden. This is one of the largest cohorts of COVID-19 pneumonia patients post-hospitalization in an outpatient setting submitted to BAL screening.

Disclosure of funding source(s): none