Sustained Three-Year Remission Following Anti-IL-6 Therapy in a Patient With TAFRO (Thrombocytopenia, Anasarca, Fever, Reticulin Fibrosis, and Organomegaly) Syndrome After Initial Misdiagnosis: A Case Report.

TAFRO syndrome is an infrequent and severe systemic inflammatory condition marked by thrombocytopenia, anasarca, fever, reticulin fibrosis/renal dysfunction, and organomegaly. Although tocilizumab has shown clinical efficacy in inducing initial disease control, evidence on sustained long-term remission beyond three years following anti-interleukin-6 therapy remains limited. We present a 46-year-old female who was admitted with worsening edema, gingival bleeding, and severe thrombocytopenia, initially misdiagnosed as idiopathic thrombocytopenic purpura with no clinical response. A comprehensive diagnostic workup demonstrated multisite serosal effusions (pleural fluid accumulation, pericardial fluid accumulation, and abdominal free fluid), enlarged cervical lymph nodes, grade 1-2 reticulin myelofibrosis with megakaryocytic hyperplasia, Castleman disease-like features on nodal histopathological examination, and increased serum interleukin-6 levels (19.2 pg/mL). The patient fulfilled all major and multiple minor diagnostic criteria for TAFRO syndrome. Treatment consisted of combination therapy with cyclophosphamide, corticosteroids, plasmapheresis, and tocilizumab administered biweekly for a total of eight doses. Complete resolution of thrombocytopenia, anemia, and inflammatory markers was observed after five cycles of tocilizumab. Comprehensive clinical, laboratory, and radiological surveillance showed sustained complete remission for more than three years, without evidence of disease relapse. This report highlights the potential role of tocilizumab-based therapy in achieving prolonged clinical remission in selected patients with TAFRO syndrome, particularly when interpreted within the overall clinical and laboratory context.