An open-labeled, single-centered, interventional, prospective study to determine the efficacy of autologous serum therapy in chronic spontaneous urticaria

BACKGROUND: Chronic spontaneous urticaria (CSU) poses a therapeutic challenge by dermatologists and patients alike. OBJECTIVES: This study aimed to find the prevalence of functional autoantibodies among patients using autologous serum skin test (ASST) and to evaluate the efficacy of autologous serum therapy (AST) as an adjuvant in CSU. MATERIALS AND METHODS: An open-labeled, single-centered, prospective, interventional study of 1 year was performed after institutional ethical approval among 55 consenting patients of CSU. ASST was performed to find the prevalence of functional autoantibodies and those positive were given weekly intramuscular AST for the next 9 weeks. For clinical outcome, weekly urticaria activity score (UAS7) was recorded at baseline and at week 10. Any adverse effects were recorded. Wilcoxon sign-ranked test and Fisher's exact test were used to demonstrate equal variance. Results: Fifty-five CSU patients consented to participate in the study; 41 were ASST+ and six were dropped out; hence, the prevalence of autoreactivity was 74.54%. Four of seven who presented with angioedema were ASST+. Thus, the prevalence of angioedema in ASST+ patients of CSU was 11.4%. At the end of 10th week, on comparing individual components of UAS7, there was a statistical significant difference (P < 0.05) in the number of wheals (P = 0.00001), pruritus (P = 0.00001), frequency of wheals (P = 0.00001), as well as the overall UAS7 (P = 0.0001) scores. The effect size is 1.23 (Cohen's d). On grading the improvement at week 10, marked (>75%), good (50%–74%), satisfactory (25%–49%), and poor (<25%) improvement were observed in 8 (22.9%), 12 (34.3%), 11 (31.4%), and 4 (11.4%) patients, respectively. CONCLUSION: AST is effective in significantly reducing wheals and pruritus and improves quality of life. It can be tried as an adjuvant before switching patient to other immunosuppressants or expensive biologicals in this current COVID-19 pandemic. Large long-term prospective randomized controlled trials with follow-up are required to conclusively ascertain the efficacy of AST as an adjuvant in CSU.