Gravimetry in sweating assessment in primary hyperhidrosis and healthy individuals

OBJECTIVE: Though hyperhidrosis is generally considered a subjectively perceived disease, it seems more and more doubtful that merely subjective evaluation is sufficient to qualify the patient to surgery. The aim of this study was to develop further gravimetry as a method of evaluation of sweating intensity and determination of the applicability of it in post-operative follow-up of primary hyperhidrosis (PHH) patients. METHODS: Total of 1,485 gravimetry assays has been performed in 343 patients treated for hyperhidrosis and in 220 healthy volunteers. In all of the subjects the measurements were taken from four localizations (face, hands, armpits and trunk) and normalized by body surface of the participant. The measurements were taken twice for every participant to obtain test–retest correlations. Mean values and standard deviations (SD) have been evaluated and on that basis reference values were quantified. Thresholds for diagnosis of hyperhidrosis were quantified on the basis of normal distribution theory as healthy population mean +2 SD. RESULTS: In healthy volunteers, mean value of gravimetrically evaluated intensity of sweating were: facial: 19.15 ± 14.97 mg/min/m(2), palmar: 18.49 ± 14.06 mg/min/m(2), axillary: 42.39 ± 47.08 mg/min/m(2) and plantar: 15.77 ± 16.87 mg/min/m(2). Thresholds for diagnosis of hyperhidrosis were quantified, respectively as: 49, 46, 136 and 50 mg/min/m(2). The overall test–retest correlation was 0.71. INTERPRETATION: Gravimetry is easy, reproducible and fast method of evaluation of sweating. The reference values are stable and can serve as a qualifying and follow-up tool for evaluation of the patients with PHH in any localization.