Froehlich syndrome (hypogonadism with obesity) results from an injury of a part of the hypothalamus (arcuatus nucleus and ventromedial nueclei. The hypothalamic gland is the endocrine gland that produces substances that stimulate the pituitary and regulate appetite. In Froehlich syndrome, the front portion (anterior) of the pituitary gland fails to secrete the hormones that are necessary for the onset of normal puberty.
The most frequent cause of Froehlich syndrome is a specific tumor of the pituitary-hypothalamus area, an expanding hollow (cystic) lesion (craniopharyngioma) or its surgical treatment (injury of this area during surgery).
Lesions resulting from inflammation from an infection such as tuberculosis or an acute inflammation of the brain (encephalitis) can also be responsible for causing Froehlich syndrome.