Infrared thermography in the diagnosis of palmar hyperhidrosis: A diagnostic study

Primary hyperhidrosis is a common condition affecting 1-3% of the general population. Excessive sweating leads to reduced surface temperature due to evaporation that can be captured using a thermal camera. We performed this study to find the utility of thermography in the diagnosis of palmar hyperhidrosis.

This was a cross-sectional diagnostic study conducted in a tertiary care dermatology center during the study period Apr 20-Mar 21. Adult patients with palmar hyperhidrosis diagnosed by expert dermatologists were recruited. The severity was assessed using the hyperhidrosis disease severity scale (HDSS). The measurements were done using a FLIR™ thermal camera. A pilot study, including 30 patients and 30 controls were performed. The results of the pilot study were used for the calculation of sample size.

The study included 55 patients and 110 controls. The mean age of the patients and controls was 22.4 (±3) years and 21.7 (±2.5) years, respectively. The mean temperature difference in the patient and control group was found to be 19.6 (±3.3)⁰ F and 5.8 (±2.9)⁰ F, respectively (p < 0.001). A receiver operating characteristics curve (ROC) to assess the discriminatory ability of mean temperature difference in diagnosis of hyperhidrosis found the area under the curve (AUC) to be 0.995 and a temperature difference of 11.5 °F provides sensitivity and specificity of 98.2% and 97.3% for the diagnosis of hyperhidrosis.

Thermal imaging is a simple, noninvasive, and objective tool for the diagnosis of hyperhidrosis. It has potential utility in monitoring the effect of the treatment.