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Ten-year Study of Lepromin Response in Child Contacts of Leprosy Patients
Insights
Leprosy contact children
Area of Science:
- Immunology
- Infectious Diseases
- Dermatology
Background:
- Leprosy remains a significant public health concern.
- Understanding immune responses in leprosy contacts is crucial for prevention and early detection.
Purpose of the Study:
- To investigate the predictive value of early and late Dharmendra lepromin reactions in leprosy contact children.
- To assess the relationship between lepromin test results and the development of leprosy over a 10-year follow-up period.
Main Methods:
- A longitudinal study involving 484 leprosy contact children and 135 non-contact children.
- Dharmendra lepromin testing (early and late responses) was performed and followed for 10 years.
- Comparison of lepromin reactions between leprosy-affected households and unaffected households.
Main Results:
- Leprosy developed in 46 contacts, predominantly among those with positive early lepromin (Fernandez) reactions.
- Only two lepromin-negative contacts developed leprosy.
- A significant disagreement was observed between early and late lepromin responses.
- Late lepromin reaction (Mitsuda) was rarely positive in children who developed leprosy.
Conclusions:
- Late lepromin reaction may indicate protective immunity against leprosy.
- Early lepromin reaction (delayed hypersensitivity) does not appear to be a reliable indicator of protection.
- Lepromin testing, particularly the late reaction, could aid in identifying individuals at higher risk.
Abstract:
In this study, 484 leprosy contact children were tested with Dharmendra lepromin and the early and late responses were recorded. These were followed-up for a period of 10 years. They were compared with lepromin reaction in 135 children who wereliving in the households where there were no leprosy cases. All the contacts and non-contacts belonged to villages in the Chingleput Taluk. Amongst contacts, the early lepromin was positive in 283 and negative in 201. Forty-six contacts developed leprosy from mostly amongst leproniin positive (Fernandez) reactors' only two-lepromin negative contacts developed leprosy. Out of the 46 children who developed leprosy, there were only two who had a 3 + late lepromin reaction (Mitsuda). Four contacts who developed borderline leprosy were negative for late lepromin reaction (Mitsuda). Amongst 135 non-contacts, only 15 children had a positive early lepromin respone whereas 90. had a positive late reaction. There was a significant disagreement between the positive earlylepromin response and the late reaction. Late lepromin reaction may be an index of protective immunity whereas the early reaction, which indicates, delayed hypersensitivity is not.
