Abstract
BACKGROUND: Immune thrombocytopenia (ITP) is an autoimmune condition often managed with corticosteroids, intravenous immunoglobulins, or thrombopoietin receptor agonists. In settings where these therapies are inaccessible or contraindicated, dapsone an older antimicrobial agent with immunomodulatory effects has been proposed as an alternative, though its comparative effectiveness and safety profile remain inadequately defined. OBJECTIVES: This study systematically reviews and synthesizes existing data to assess the efficacy and tolerability of dapsone in adult patients with ITP. METHODS: Following PRISMA guidelines, a literature search across PubMed, Embase, and Cochrane databases identified observational studies and interventional trials evaluating dapsone in ITP, including comparisons with standard treatments. Primary outcomes included complete and overall response rates, hemoglobin variation, relapse frequency, and adverse effects. Risk of bias was evaluated using the Newcastle-Ottawa Scale and Cochrane tools. Meta-analysis was conducted using RevMan and R (meta/metafor). RESULTS: Four eligible studies encompassing over 270 patients were analyzed. The pooled complete response rate was 28%, while the overall response rate reached 47%. Dapsone use was associated with a modest decline in hemoglobin levels with a mean decrease of 1.74 g/dL, and relapse occurred in approximately 21% of patients. Adverse effects most commonly hemolytic anemia and methemoglobinemia were reported in 18% of patients, though generally not severe. Heterogeneity was explored through leave-one-out sensitivity analyses. CONCLUSIONS: Dapsone demonstrates moderate efficacy and an acceptable safety profile in adult ITP patients, especially in resource-limited contexts. While it may not match thrombopoietin agonists in preventing relapse, its low cost and oral administration offer practical advantages. Further large-scale randomized trials are warranted to clarify its role in ITP management.