Tuberculine reaction measured by infrared thermography

• First paper devoted to tuberculine reaction measurement based on thermal imaging.
• There is good agreement in area length of tuberculin reaction between visual and thermographic evaluation.
• Automatic generation of positive and negative results of the tuberculin skin test evaluated by infrared imaging.

SettingThe infection with Mycobacterium tuberculosis gives a delayed immune response, measured by the tuberculine skin test. We present a new technique for evaluation based on automatic detection and measurement of skin temperature due to infrared emission.Design34 subjects (46.8 ± 16.9 years) (12/22, M/F) with suspected tuberculosis disease were examined with an IR thermal camera, 48 h after tuberculin skin injection.ResultsIn 20 subjects, IR analysis was positive for tuberculine test. Mean temperature of injection area was higher, around 1 °C, for the positive group (36.2 ± 1.1 °C positive group; 35.1 ± 1.6 °C negative group, p < 0.02 T test for unpaired groups).ConclusionIR image analysis achieves similar estimation of tuberculin reaction as the visual evaluation, based on higher temperature due to increased heat radiation from the skin lesion.