What are the symptoms of kidney deficiency and kidney yang deficiency?

Kidney deficiency can be divided into kidney-yang deficiency and kidney-yin deficiency. Kidney-yang deficiency patients are mainly manifested as backache, weakness of limbs, fear of cold, cold hands and feet, loss of appetite, insomnia, loss of libido, impotence, premature ejaculation, etc. Kidney-yin deficiency patients are mainly manifested as hot flashes and excessive sweating, soreness of the waist and knees, dry mouth and thirst, dry throat, dry skin and other symptoms.