Edema due to altered sweating function.

We report a case with idiopathic edema accompanied with excessive sweating on bathing. The subject is a 26 year-old male. He was admitted to our hospital because of pretibial edema. He complained of excessive sweating only after daily bathing. Sweating on daily bathing reduced pretibial edema after long-term standing. Daily urine volume decreased by about 200 to 500 mL/day on bathing everyday. Plasma renin, aldosterone and bradykinin levels increased. Subcutaneous injection of pilocarpine increased sweating around the injection site. The cessation of daily bathing restored plasma renin, aldosterone and bradykinin levels; urine volumes increased. However, pretibial edema appeared and body weight increased by 8.5 Kg. Serum triiodothyronine (T3), thyroxine (T4) levels and basal metabolic rate (BMR) decreased. Circulating plasma volume increased with the cessation of bathing. Alterations in the autonomic nervous system may be involved in the appearance of general edema through increased plasma volume due to altered sweating function.