Clinical Features and Outcome Analysis of Type B Insulin Resistance Syndrome: A Single-Center Study in China

CONTEXT: Type B insulin resistance syndrome (TBIRS) is a rare condition, for which effective treatment remains challenging. OBJECTIVE: This work aimed to summarize the clinical characteristics of TBIRS and explore effective therapeutic strategies. METHODS: The clinical manifestations, biochemical indices, and treatment of 8 patients (3 men and 5 women) with TBIRS from Peking Union Medical College Hospital were retrospectively analyzed and their clinical outcomes were evaluated. RESULTS: The average age of the patients was 49.5 ± 16.5 years, and the duration of the disease ranged from 2 months to 1 year. Seven patients with hyperglycemia had normal/lower triglycerides (TGs) and lower insulin-like growth factor 1 (IGF-1) levels. One patient complained of intractable hypoglycemia. Five patients had accompanied systemic lupus erythematosus, 2 had mixed connective tissue disease, and 1 had undifferentiated connective tissue disease. Five patients had acanthosis nigricans and 3 women of child-bearing age had hyperandrogenism. All 8 patients were treated with glucocorticoids combined with immunosuppressants, among whom, 5 received high-dose glucocorticoid pulse therapy followed by conventional-dose glucocorticoid therapy, all of whom achieved partial remission within 2 to 4 weeks. Among the 3 patients receiving conventional glucocorticoid therapy, 2 achieved partial remission within 2 to 4 weeks. Six patients were tracked for 10 weeks to 4 years; 4 and 2 achieved complete and partial remission, respectively. CONCLUSION: Decreased serum complement 3 and IGF-1 levels and normal/decreased TG levels act as striking biochemical features of TBIRS. High-dose glucocorticoid pulse therapy followed by conventional-dose long-term therapy combined with immunosuppressants achieves good clinical efficacy.