Abstract
We report a case of persistent lupus anticoagulant (LAC) positivity following mild COVID-19 in a 64-year-old Japanese male with a history of atrial fibrillation. The patient experienced post-COVID-19 condition symptoms, including intermittent fatigue, taste disturbance, and persistent numbness in the upper arm, persistently for over 10 months. Laboratory investigations revealed prolonged activated partial thromboplastin time (aPTT) of 70.0 seconds, positive LAC of 1.5, and positive anti-cardiolipin-beta2-glycoprotein I complex antibody of 4.3 U/mL. This case highlights the potential for long-term LAC positivity after mild COVID-19 and raises questions about its association with post-COVID-19 conditions. The persistence of LAC positivity is noteworthy, as previous studies suggest that virus-induced LAC typically resolves within two to three months. Further research is needed to elucidate the long-term dynamics of LAC in post-COVID-19 condition patients and its clinical implications, particularly in relation to thrombotic complications associated with COVID-19.