Evaluation of skin temperature in the hands of leprosy patients to detect peripheral autonomic dysfunction, by infrared thermography

Objective This study analyzed the potential of thermography to detect abnormalities in the skin temperature of the hands of leprosy patients, and thus to provide evidence of autonomic impairment in these patients. Methods In this cross-sectional study, 22 healthy subjects and 48 leprosy patients (16 borderline tuberculoid (BT), 10 mid-borderline (BB), 10 borderline lepromatous (BL) and 12 lepromatous (LL) patients) were recruited in a leprosy national reference center in Brazil. The patients were diagnosed based on clinical and laboratory tests. Infrared thermography was used to measure skin temperature at ten sites in each hand. Results The skin temperature, observed by IR thermography images of the dorsal and palmar surfaces of the hands, was diminished in leprosy patients, compared of healthy subjects (p < 0.05). The LL patients were the most affected group. Considering the presence of asymmetric temperature in two or more 'regions of interest' (ROI) as a possible abnormality, only 13.6% (3/22) of healthy individuals showed this asymmetry, while in the group of patients with leprosy 50.0% (24/48) showed an asymmetrical pattern in hand temperature distribution (p < 0.05). Conclusion This study presented a potential benefit in using IR thermography to evaluate asymmetry of skin temperature in the hands of leprosy patients, thus detecting peripheral autonomic dysfunction. Keywords: Mycobacterium leprae, peripheral nerves, thermography, microcirculation