Type 1 and Type 2 lepra reactions in leprosy: association with clinical spectrum, co-infections, and anti-PGL-1 antibody levels

Background

Leprosy is a chronic infectious disease further complicated by severe systemic immune-mediated reactions known as lepra reactions. Various risk factors have been assessed to diagnose high-risk patients who develop lepra reactions. Identifying high-risk patients is crucial, yet data on associated risk factors, especially from India, remain limited.

Objective

This study aimed to evaluate clinical, epidemiological, and serological risk factors risk factors for leprosy reactions.

Method

This cross-sectional analytical study assessed various clinical and epidemiological variables, co-infections (dental, respiratory, urinary tract, and parasitic), laboratory parameters, and anti-PGL-1 antibody levels as potential risk factors.

Results

The study included 70 leprosy patients, 30 with leprosy reactions (15 each with Types 1 and 2) and 40 without reactions. The data analysis was done using the Statistical Package for Social Sciences (SPSS) software, manufactured by IBM in Chicago, USA, version 25.0 for Windows. Borderline leprosy was significantly associated with Type 1 lepra reactions. Type 2 reactions were significantly linked with the lepromatous spectrum, high bacillary index (≥3), leucocytosis, thrombocytosis, and co-infections including dental and lower respiratory tract infections. Anti-PGL-1 antibody levels were significantly elevated in patients with Type 2 reactions and correlated with reaction severity.

Conclusion

This is the first study from India to delineate distinct risk factors for Type 1 and Type 2 lepra reactions. Type 1 reactions are more frequent in borderline leprosy, while Type 2 reactions are associated with high bacillary load and intercurrent infections. Elevated anti-PGL-1 antibody levels serve as an indicator for Type 2 lepra reactions and could aid in prognosis and treatment.