Central Nervous System Diseases; Hypothalamic Diseases; Hypothalamic Hormones; Hypothalamo-Hypophyseal System/drug effects; Pituitary Hormones; Sarcoidosis; Adult; Aged; Biopsy; Case-Control Studies; Central Nervous System Diseases/diagnosis; Central Nervous System Diseases/drug therapy; Central Nervous System Diseases/metabolism; Central Nervous System Diseases/physiopathology; Child; Drug Monitoring; Female; Glucocorticoids/administration & dosage; Humans; Hypothalamic Diseases/diagnosis; Hypothalamic Diseases/drug therapy; Hypothalamic Diseases/metabolism; Hypothalamic Diseases/physiopathology; Hypothalamic Hormones/analysis; Hypothalamic Hormones/metabolism; Hypothalamo-Hypophyseal System/physiopathology; Hypothalamus/metabolism; Hypothalamus/pathology; Magnetic Resonance Imaging/methods; Male; Pituitary Gland/metabolism; Pituitary Gland/pathology; Pituitary Hormones/analysis; Pituitary Hormones/metabolism; Prednisone/administration & dosage; Sarcoidosis/diagnosis; Sarcoidosis/drug therapy; Sarcoidosis/metabolism; Sarcoidosis/physiopathology; Treatment Outcome