Clarithromycin in Post COVID-19 Organizing pneumonia.

To the Editor, An increasing number of patients are reporting with symptoms secondary to post COVID-19 pulmonary sequelae. Radiological findings in these patients include fibrotic lung disease, interstitial lung abnormalities, ground glass opacities, and organizing pneumonia (OP). Therapeutic options in these patients include steroids and anti-fibrotics. The majority of these patients have received steroid therapy for COVID-19 pneumonia, and may continue to receive it for post COVID-19 pulmonary sequelae, subjecting themselves to steroid related adverse effects. Cryptogenic organizing pneumonia (COP) responds well to steroid therapy. Alternatively, macrolide therapy has been successful in the treatment of both cryptogenic and secondary forms of OP. Compared to steroid therapy, macrolide therapy in COP is well tolerated and associated with fewer adverse events. We report two patients who were diagnosed with post COVID-19 OP who were treated successfully with clarithromycin for three months. We believe that clarithromycin offers a potential therapeutic option in post COVID-19 organizing pneumonia. Our first patient was a seventy-year-old female who presented with non productive cough and exertional dyspnea of two weeks duration. Two weeks ago, she was discharged after being hospitalized for twelve days for COVID-19 pneumonia with hypoxemia, and was treated with oxygen therapy, once daily subcutaneous low molecular weight heparin (LMWH), intravenous methylprednisolone and remdesivir. On discharge, since she continued to remain hypoxemic, she was advised to continue oral dexamethasone 6 milligram (mg) per oral (PO) (tapering doses) along with home oxygen with recommended flow of two liters per minute, with which, she maintained a peripheral saturation of 94%, for another ten days post discharge. She had no other past medical history. Clinical examination revealed a respiratory rate of 18 per minute with peripheral saturation of 95% with room air, and she had discontinued home oxygen two days ago. She had bilateral inspiratory crepitations on chest auscultation. Computed tomography (CT) of chest presently revealed bilateral peripheral interlobar septal thickening with ground glass opacities in both upper and lower lobes, along with lower lobe predominant peribronchovascular and subpleural coalescing consolidation and areas of peripheral perilobular pattern of thickening surrounding an area of normal attenuation with a solid nodule within its center, suggestive of the target sign (Figure 1). Overall, the radiology was suggestive of organizing pneumonia (OP). She was initiated on oral clarithromycin PO 500 mg twice daily for three months. She was reviewed monthly, during which her symptoms were reported to have Letter to Editor