Repetitive post-tonsillectomy hemorrhage subsequently diagnosed as lupus anticoagulant-associated coagulopathy in a child.

Transient positivity of anti-phospholipid antibodies can be induced by infectious diseases, and may occasionally cause prolonged activated partial thromboplastin time (APTT). In most cases, this phenomenon is asymptomatic and does not require therapeutic intervention. However, in rare instances, patients with lupus anticoagulant (LA), a type of anti-phospholipid antibody, develop coagulopathy due to decreased activity of coagulation factors, resulting in an acquired bleeding tendency. When both acquired hypoprothrombinemia and LA are present, the condition is diagnosed as LA-hypoprothrombinemia syndrome (LAHPS). A similar condition with decreased activity of coagulation factors other than prothrombin is referred to as LAHPS-like syndrome (LLS). Given the clinical and pathophysiological similarities between LAHPS and LLS, their integration under the concept of LA-associated coagulopathy (LAAC) has been proposed. We herein report the case of a previously healthy 5-year-old girl who developed recurrent postoperative bleeding after tonsillectomy and adenoidectomy. Laboratory tests revealed prolonged APTT and positivity for LA. As the patient had experienced streptococcal tonsillitis 7 weeks before surgery, the condition was considered to be infection-triggered LAAC. Although LAAC is rare, careful perioperative monitoring is required in pediatric surgical patients, who are prone to infections.