Severe intraoperative bleeding as the initial manifestation of de novo immune thrombocytopenia during lumbar spinal fusion: a case report.

PURPOSE: Immune thrombocytopenia (ITP) rarely presents intraoperatively during spinal surgery. We report a case of de novo ITP that first manifested as severe, uncontrolled bleeding during lumbar spinal fusion despite normal preoperative platelet count and coagulation tests. METHODS: The clinical course, perioperative laboratory findings, diagnostic workup, and treatment follow-up of an elderly woman who developed acute severe thrombocytopenia during L2-5 posterior lumbar interbody fusion were reviewed. RESULTS: An 81-year-old woman underwent L2-5 posterior lumbar interbody fusion for degenerative lumbar spondylolisthesis. Preoperative platelet count and coagulation parameters were normal. During intervertebral procedures, diffuse oozing bleeding progressively increased without apparent arterial injury, and intraoperative coagulation tests remained unremarkable. On postoperative day 1, the platelet count decreased to 1,000/µL and showed minimal response to platelet transfusion. After exclusion of other causes, de novo ITP was diagnosed. Intravenous immunoglobulin and corticosteroids were insufficient, but platelet recovery occurred after thrombopoietin receptor agonist therapy. Systemic bleeding manifestations included alveolar hemorrhage, purpura, and hematuria. No recurrence of ITP was observed at 1 year. CONCLUSION: Acute ITP should be considered when unexplained diffuse intraoperative bleeding occurs during spinal surgery despite normal coagulation tests. Early reassessment of platelet counts and hematology consultation may facilitate timely diagnosis and treatment.