What diseases and disorders do endocrinologists treat other than diabetes?

Many! Problems of the pituitary, thyroid, adrenals, parathyroids, menopause*, testosterone*, fertility*, bones. Imbalances of sodium, potassium, calcium, magnesium, phosphate, vitamin d. Problems of various glans may be over/under-production of hormones, masses/tumors, or cancers. Individual endocrinologists tend to have areas of interest, and not all will treat all conditions (especially * issues).