Clinical evolution of antisynthetase syndrome-associated interstitial lung disease after COVID-19 in a man with Klinefelter syndrome: A case report

BACKGROUND This study presents a case of rapidly developing respiratory failure due to antisynthetase syndrome (AS) following coronavirus disease 2019 (COVID-19) in a 33-year-old man diagnosed with Klinefelter syndrome (KS). CASE SUMMARY A 33-year-old man with a diagnosis of KS was admitted to the Department of Pulmonary and Critical Care Medicine of a tertiary hospital in China for fever and shortness of breath 2 wk after the onset of COVID-19. Computed tomography of both lungs revealed diffuse multiple patchy heightened shadows in both lungs, accompanied by signs of partial bronchial inflation. Metagenomic next-generation sequencing of the bronchoalveolar lavage fluid suggested absence of pathogen. A biopsy specimen revealed organizing pneumonia with alveolar septal thickening. Additionally, extensive auto-antibody tests showed strong positivity for anti-SSA, anti-SSB, anti-Jo-1, and anti-Ro-52. Following multidisciplinary discussions, the patient received a final diagnosis of AS, leading to rapidly progressing respiratory failure. CONCLUSION This study underscores the clinical progression of AS-associated interstitial lung disease subsequent to viral infections such as COVID-19 in patients diagnosed with KS.