Male patients who experience sweating in the lumbar fossa, that is, sweating around the posterior superior iliac crest, are often due to the following causes: 1. It may be due to kidney yin deficiency. This is often seen in men who have recently overworked, which then leads to kidney yin deficiency, where there will be night sweats, in addition to heat in the hands and feet, waist weakness, and a dry mouth. 2, this situation may also be due to the waist by the damp-heat evil invasion caused by. For example, if the patient works in a hot, humid environment for a long time and exposes the waist to the elements, it may cause the area to be infected with damp heat, which in turn causes back pain and makes the area sweat. 3. This condition is also common when the patient keeps the area excessively warm. Some patients with chronic low back pain will do too much warmth in this area and then make it sweat.