Prognostic evaluation of cell mediated immunity in leprosy and correlation with clinicopathological status of leprosy patients.

Cell mediated immunity was studied in 50 patients of leprosy and 15 control volunteers, by estimation of peripheral blood lymphocytes (PBL), total rosette forming cells (TRFC) and active rosette forming cell (ARFC) counts in vitro. PBL, TRFC and ARFC counts were slightly but not significantly increased in patients of tuberculoid leprosy (TT) and muculoanaesthetic variant of tuberculoid leprosy as compared to control group. However, gradual decrease in T-cell subsets, occurred in borderline tuberculoid leprosy (BT) as compared to tuberculoid type (TT)-(p < 0.05). Significant decrease in lymphocytes and T-cell subsets was observed in midborderline leprosy (BB), (p < 0.01):borderline lepromatous leprosy (BL), (p < 0.001) and lepromatous subpolar and polar types (LL); (p < 0.001) as compared to control group. Mycobacterium leprae (M.leprae) were positive in BT-(20%); BB-(72.7%); BL-(83.2%) and LL-(100%). Delayed hypersensitivity reactions (DHR) revealed significantly increased lepromin positivity in TT (83.3%) and BT (80%) which decreased in BB (63.6%) and BL (50%). Lepromin test showed anergic state in LL group (28.5% positivity). Dinitrochlorobenzene (DNCB) skin test showed 100% positivity in TT group and controls while gradual significant decrease was observed from BT (p < 0.05) to LL scale (p < 0.001). Leprosy spectrum of Ridley and Jopling scale is directly co-related with inherent cell mediated immune status of the patients which has a significant prognostic role in treatment and long term management.