ABSTRACT
Introduction: Acute fibrinous and organizing pneumonia (AFOP) is a rare histological pattern of lung injury. Organizing Pneumonia (OP) may be occurring more frequently than realized in patients with lung injury from COVID-19. This case report reviews the presentation and disease course of AFOP in a patient with COVID-19. Case description:A 49-year-old male with a history of Diabetes Mellitus and Chronic Lymphocytic Lymphoma on Venetoclax and Obinutuzumab presented with fever, exertional dyspnea, and dry cough and was diagnosed with COVID-19. His CT scan showed extensive peripheral predominant patchy and heterogenous ground glass opacities with mediastinal lymphadenopathy (Image A). His serum aspergillus galactomannan index was 4.37 and he was started on voriconazole. He however remained febrile;so, he had a transbronchial cryobiopsy. His pathology revealed marked interstitial T-cell lymphocytic inflammatory infiltrate with fibrinous and organizing pneumonia. There was proliferative bronchiolitis and evidence of acute pulmonary hemorrhage, without features of vasculitis/capillaritis. No evidence of malignancy or organisms were identified. He was started on methylprednisolone daily and he initially improved, however, his fever returned and his oxygen requirements increased rapidly with steroid taper. His repeat chest CT scan showed a marked increase in bilateral patchy areas of consolidation with surrounding areas of ground glass opacity and intralobular septal thickening ("crazy paving") Image B. His infectious work up was extensive but negative. At this point, he required invasive mechanical ventilation;after which he received pulse dose steroids for three days followed by high dose maintenance. He improved and was extubated. However, he required high flow supplemental oxygen and was unable to be weaned past 100% fraction of inspired oxygen;as a result, Ruxolitinib was added. Unfortunately, his hypoxemia remained refractory and he developed sudden cardiovascular collapse which led to his demise. The patient died 40 days after admission. Discussion: Understanding the histopathology, disease course, and sequelae of COVID-19 is of paramount importance, because AFOP in COVID-19 adds complexity to management. Our patient's antemortem biopsy was performed prior to acute respiratory distress syndrome and mechanical ventilation as opposed to previous case reports with post mortem findings of AFOP after prolonged mechanical ventilation. Notably, 30% - 60% of intensive care patients with SARS CoV 1 had OP and AFOP. Additionally, the CT findings of COVID-19 are similar to OP and this lends support to the possibility that OP is an underlying pattern of lung injury in COVID-19.