CASE OF PULMONARY FIBROSIS FROM COVID PNEUMONIA

ABSTRACT

SESSION TITLE Medical Student/Resident Lung Pathology SESSION TYPE Med Student/Res Case Rep Postr PRESENTED ON October 18-21, 2020 INTRODUCTION: Coronavirus disease 2019 (Covid-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a devastating ongoing global pandemic. Its disease severity ranges from asymptomatic, mild to severe disease, which can be complicated by developing hypoxemic respiratory failure and acute respiratory distress syndrome (ARDS). Pulmonary fibrosis is condition that occurs due to scarring of lung tissue. Most common cause being idiopathic occurring over a long period of time but it can also occur several days after severe bacterial pneumonias due to activation of fibroblasts. Our case shows that Covid-19 infection can acutely cause pulmonary fibrosis. CASE PRESENTATION A 76-year old woman, life time non-smoker, with a history of well controlled intermittent asthma (rescue inhaler only) never hospitalized for any exacerbations. She was transferred to our facility due to persistent oxygen requirements after diagnosed with Covid-19 pneumonia. She presented to an outside hospital 3 months prior with fever and shortness of breath. Her course was complicated with hypoxemia requiring oxygen via non-rebreather mask, bilateral lower extremity deep vein thrombosis requiring apixaban. Her oxygen requirement slowly improved to 2 liters via nasal cannula. Despite clinically improvement she became oxygen dependent. She failed weaning off oxygen multiple times. CT of her chest even showed predominant upper lobe scarring. She was discharged home with oxygen 5 months after her Covid-19 pneumonia diagnosis. DISCUSSION: Pulmonary fibrosis leads to lung scarring. Fibrotic tissue is dead tissue, no gas exchange happens and there is a restrictive pattern on Pulmonary function tests (PFTs). There are many different conditions that can lead to pulmonary fibrosis but it is not common to develop post viral infections. Classic Covid-19 pneumonia causes diffuse bilateral infiltrates causing severe inflammatory response leading to macrophage activation, cytokine release with activation and proliferation of fibroblasts causing tissue destruction and scarring. Except for well controlled intermittent asthma our patient did not have any underlying lung etiologies that could make her oxygen dependent. She is a life time non-smoker, no occupational exposure to any chemicals, pollutants, toxic fumes etc., no history of autoimmune diseases or connective tissue diseases, no radiation exposure, no usage of any pulmonary toxic medications like amiodarone, bleomycin. Review of old medical records and imaging did not show any evidence of pulmonary fibrosis. Unfortunately, there were no post Covid-19 PFTs available for comparison. CONCLUSIONS: Covid-19 pneumonia with diffuse bilateral infiltrates can rapidly progress into pulmonary fibrosis due to severe inflammatory response/cytokine storm (post-COVID fibrotic ARDS), which made our patient oxygen dependent with significant reduction in her quality of life. Reference #1 Belloli EA, Beckford R, Hadley R, Flaherty KR. Idiopathic non-specific interstitial pneumonia. Respirology. 2016 FEb.21(2) 259-68 Reference #2 Zhu N Zhang D Wang W et al.A novel coronavirus from patients with pneumonia in China, 2019.N Engl J Med. 2020;382 727-733 DISCLOSURES No relevant relationships by Moses Bachan, source=Web Response No relevant relationships by Zinobia Khan, source=Web Response No relevant relationships by swetha Nadella, source=Web Response No relevant relationships by Robert Siegel, source=Web Response No relevant relationships by Vijaya Vudathaneni, source=Web Response