Comparative trail on efficacy of topical contact immunotherapy with dinitrochlorobenzene and diphenylcyclopropenone in alopecia areata

Abstract
Alopecia areata is a common chronic inflammatory disorder of hair characterized by non-scarring type of hair loss involving scalp, face and other areas of the skin. It can be classified as localized alopecia areata with patchy areas of hair loss, alopecia total is involving the diffuse scalp and alopecia universal is involving the entire body. Extensive and recalcitrant type of AA can cause significant challenge to treating physician. Alopecia areata is a self-limiting disorder. It can be managed with topical corticosteroids, anthralin and minoxidil. Active and extensive cases of AA can be managed with oral corticosteroids, cyclosporine, azathioprine, methotrexate and photochemotherapy. Topical immunotherapy is an effective modality yet underexplored treatment option available for managing resistant and recalcitrant cases of AA. In this study we have compared two topical immunotherapeutic agents; dinitrochlorobenzene (DNCB) and diphenylcyclopropenone (DPCP) in the treatment of alopecia areata. A total of 30 patients with alopecia areata who had given written consent to undergo therapy with DNCB and DPCP were included in the study. They were randomly categorized into two groups namely DNCB group received DNCB and the second group was called DPCP group received DPCP. Initial sensitization testing was done over on inner arm with 2% solution which induces inflammatory changes of allergic contact dermatitis. After positive inflammatory changes at the sensitization site, DNCB/DPCP was applied to patients in increasing serial concentrations on weekly basis starting from 0.001% upto 2%. Inflammatory changes usually occurred after 24 to 48 hours. The patients were followed every week for six months. Treatment outcome of both the groups were compared at the end of six months. The desirable regrowth of hair (patchy or complete regrowth of terminal hairs; grade III and IV) was found to be 86.7% in DPCP group when compared to 33.3% in DNCB group. DPCP is found to be more effective in managing chronic treatment failure and recalcitrant cases of alopecia areata than DNCB from our study. Thick pigmented anagen hairs which were more persistent were achieved in DPCP group than DNCB group. To conclude DPCP is more effective in the management of AA with lesser side effects when compared to DNCB. Overall both topical immunotherapeutic agents can produce hair growth but DPCP is more tolerated with more response rates.