Role of Histopathology in Predicting type 1 Lepra Reaction in Borderline Tuberculoid Leprosy

Lepra reactions if not managed promptly are an important cause of sudden onset nerve palsy and disability due to leprosy.

To evaluate the usefulness of histology in predicting type 1 lepra reaction.

After obtaining clearance from institutional research and ethics committees, all histologically proven borderline tuberculoid patients diagnosed at our center from 1.8.2016 to 31.7.2018 were included in this retrospective cross-sectional study.

Clinical details were collected from patient records. The pathologist who was blinded to clinical evidence of type 1 lepra reaction at the time of biopsy re-evaluated the histopathology slides for evidence of type 1 reaction. The data of individual patient was analyzed to identify those who had a type 1 reaction at the time of the biopsy or who developed a lepra reaction during follow up.

Association between histological evidence of type 1 reaction and clinical manifestation of the same subsequently, was assessed using Pearson's Chi square test.

Study group comprised of 22 females and 18 males. Clinicohistological concordance was noted in 27 patients (67.5%). Subclinical type 1 reaction was documented in 11 patients (27.5%) based on histopathology evaluation. Five (45.5%) of these 11 patients subsequently developed clinical features of type 1 reaction. This was found to be statistically significant (P value 0.02).

Main limitation was the small sample size.

Histology could serve as a useful tool in predicting future type 1 lepra reaction.