Asymptomatic leprosy contacts present asymmetrical skin temperature in hands by infrared thermography

Objective: This study aimed to identify possible dysautonomia in asymptomatic leprosy contacts through the assessment of asymmetric temperature between the hands using Infrared Thermography (IR).

Methods: We recruited 144 subjects divided in three groups: 23 healthy subjects, 66 seropositive and 55 seronegative leprosy contacts by anti-phenolic glycolipid I (anti-PGL1) serology. Skin temperature was measured by a FLIR^® T420 IR camera at ten regions of interest (ROIs) in each hand, at a controlled room temperature.

Results: Skin temperature of both hands was reduced ( p < 0.05) on all ROIs in seropositive household contacts and in the three ROIs of distal phalanges in seronegative contacts ( p < 0.05) compared with healthy subjects. The presence of 2 or more ROIs with temperature asymmetry was observed in 81.8% (54/66) of seropositive and 60.0% (33/55) in seronegative contacts.

Conclusion: IR thermography may detect temperature asymmetry in hands of leprosy contacts indicating peripheral autonomic dysfunction related to early neural impairment in these individuals.