Autologous serum therapy in chronic urticaria: Old wine in a new bottle

Background: Chronic urticaria (CU) is one of the most challenging and frustrating therapeutic problems faced by a dermatologist. A recent demonstration of abnormal type 1 reactions to intradermal autologous serum injections in some CU patients has led to the characterization of a new subgroup of "autoimmune chronic urticaria". This has rekindled interest in the age-old practice of autologous blood injections as a theoretically sound treatment option in these patients. Aims: To evaluate the efficacy of repeated autologous serum injections (ASIs) in patients with recalcitrant chronic urticaria. Methods: A cohort of 62 (32 females) CU patients with a positive autologous serum skin test (ASST) (group 1) was prospectively analyzed for the efficacy of nine consecutive weekly autologous serum injections with a postintervention follow-up of 12 weeks. Another group of 13 (seven females) CU patients with negative ASST (group 2) was also treated similarly. In both groups, six separate parameters of disease severity and activity were recorded. Results: Demographic and disease variables were comparable in both groups. The mean duration of disease was 1.9 0.3 years (range = 3 months to 32 years) in group 1 and 1.5 +/- 0.2 years (range = 3 months to 10 years) in group 2. In the ASST (+) group, 35.5% patients were completely asymptomatic at the end of the follow-up while an additional 24.2% were markedly improved. In the ASST (-) group, these figures were 23 and 23% respectively. The intergroup difference for complete subsidence was statistically significant (P < 0.05). In both groups, the most marked reduction was seen in pruritus and antihistamine use scores followed by the size and frequency of the wheals. Conclusion: Autologous serum therapy is effective in a significant proportion of ASST (+) patients with CU. A smaller but still substantial number of ASST (-) patients also benefited from this treatment.