Tocilizumab in the treatment of hyperferritinemic syndrome and capillary leak syndrome secondary to rheumatoid arthritis: Case report and literature review.

INTRODUCTION:Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease, which is mainly characterized by joint swelling, pressure pain and joint destruction. Some patients may suffer from a variety of serious complications, which require prompt diagnosis and treatment. Otherwise, the patient condition may deteriorate rapidly, leading to premature death. OBJECTIVE:We reported a case of RA combined with hyperferritinemic syndrome and capillary leak syndrome (CLS) that was successfully treated with tocilizumab (TCZ), with the aim of improving diagnostic ideas for clinicians and consequently improving the diagnosis and treatment of the hyperferritinemic syndrome and CLS. CASE SUMMARY:A 55-year-old female patient was admitted to the Department of Infectious Diseases of our hospital due to "recurrent fever for more than 1 month and aggravation for 3 days." The patient was diagnosed with fever of unknown origin (lung infection?) and received anti-infective therapy with large encirclement of anti-bacterial, antifungal and empirical anti-tuberculosis successively during hospitalization in the Department of Infectious Diseases. Yet her condition continues to progress. The patient was eventually diagnosed with RA combined with hyperferritinemic syndrome and CLS. Then she received glucocorticoids (GC) (160 mg qd) combined with intravenous immunoglobulin (IVIG, 20 g/d, for 3 days). We considered that the patient also had an overwhelming proinflammatory cytokine storm, so she received a strong anti-inflammatory treatment with TCZ (400 mg qm). The patient symptoms and follow-up chest CT showed significant improvement following treatment. CONCLUSION:TCZ has good efficacy in the treatment of RA combined with hyperferritinemic syndrome and CLS and is expected to be a promising treatment.