Information on the following diseases can be found in the Related Disorders section of this report:

• Prader Willi Syndrome
• Bardet-Biedl Syndrome
• Borjeson Syndrome
• Hypogonadotrophic Hypogonadism

Froehlich syndrome is a rarely encountered condition that occurs mainly in males and is characterized by obesity, small testes, and a delay in the onset of puberty. Development of secondary sexual characteristics and physical growth is also delayed. Children with this syndrome tend to be short in stature. They may have malformed or undersized fingernails, and headaches are common. Some children with Froehlich syndrome may develop mental retardation, difficulties with vision, and in rare cases diabetes mellitus. (For more information on this disorder, choose "Diabetes" as your search term in the Rare Disease Database.)

Other symptoms of the syndrome may include excessive thirst (polydipsia), excessive urination (polyuria), and very delicate skin.

Froehlich syndrome is usually the result of lesions in the hypothalamic gland, the endocrine gland that produces substances that stimulate the pituitary and regulate the appetite. In some cases of Froehlich syndrome, the front portion (anterior) of the pituitary gland fails to secrete the hormones that are necessary for the onset of normal puberty. A diseased area (lesion) in the hypothalamus or pituitary is the usual cause of the syndrome. A tumor of the pituitary that is frequently the cause of damage to the hypothalamus in children and adolescents is an expanding hollow (cystic) lesion (craniopharyngioma).

Inflammation from an infection such as tuberculosis or an acute inflammation of the brain (encephalitis) are other injuries that may be responsible for the lesion and, hence, the condition.

Froehlich syndrome is a very rare condition that affects more males than females.

Symptoms of the following disorders can be similar to those of Froelich's yndrome. Comparisons may be useful for a differential diagnosis:

Prader Willi Syndrome is a complex disorder affecting many systems in the body. It is diagnosed more often in males born after a prolonged, delayed birth often in the breech position and is characterized by muscular weakness and failure to thrive during infancy. As the child grows there is a decrease in the function of the testes or ovaries (hypogonadism), short stature, and impaired intellectual capabilities. The need to eat an extraordinary amount of food (hyperphagia) usually develops between 1 and 3 years of age. If left uncontrolled, the obesity of Prader Willi Syndrome can lead to life- threatening heart and lung complications. (For more information on this disorder, choose "Prader Willi" as your search term in the Rare Disease Database.)

Bardet-Biedl Syndrome is a rare disorder affecting many systems in the body. It is inherited as an autosomal recessive genetic trait. The major symptoms of this disorder may include mental retardation, obesity, delayed sexual development, underdeveloped reproductive organs, degeneration of the retina of the eyes, kidney abnormalities, and/or abnormal fingers or toes. This disorder affects males and females in equal numbers.

Borjeson Syndrome is a rare disorder thought to be inherited as an X- linked dominant genetic trait with less severe symptoms in females. Major characteristics of this disorder may include an unusual facial appearance, mental retardation, seizures, short stature, slowed sexual development, muscle weakness and/or obesity.

Hypogonadotropic hypogonadism (secondary hypogonadism) is a disorder that effects the development of the region of the hypothalamus that regulates the production of hormones which stimulate the ovaries or testes (gonadotropins). People with this disorder have reduced levels of hormone secretion, and experience a delay in the development or absence of secondary sexual characteristics.

Diagnosis
Laboratory analysis of the urine from children with Froehlich syndrome typically reveals low levels of pituitary hormones, and that finding may suggest the presence of a lesion on the pituitary. Additional tests are needed before a definite diagnosis of Froehlich syndrome may be made.

Treatment
Pituitary extracts may be administered to replace the missing hormones (hormonal replacement therapy) in patients with Froehlich syndrome. Tumors of the hypothalamus should be surgically removed if possible. Appetite may be very difficult to manage, although weight control depends on this.

Neurosurgeons in Russia have reported good results in the treatment of Froehlich syndrome by means of relatively new stereotactic-planning (3-dimensional) of a transnasal surgical procedure to remove small tumors in the pituitary gland. Because the number of patients involved was small, much more study of this procedure is needed to determine its safety and usefulness in treating individuals affected by Froehlich syndrome.

TEXTBOOKS
Reichlin S. Neuroendocrinology. In: Wilson JD, Foster DW. Eds. Textbook of Endocrinology. 8th ed. W.B. Saunders Company. Philadelphia, PA; 1992:192-93.

Styne Dm. Disorders of Puberty: Delayed Puberty. In: Sperling MA. Ed. Pediatric Endocrinology. 1st ed. W.B. Saunders Company. Philadelphia, PA; 1996:454-460.

JOURNAL ARTICLES
Ogura T, Tobe K, Mimura Y et al. Testosterone modulates serum leptin concentratyions in a male patient with hypothalamic hypogonadiam. J Endocrinol Invest. 2000;23:246-50.

Citron JT, Ettinger B, Rubinoff H, et al. Prevalence of hypothalamus-pituitary imaging abnormalitioes in impotent men with secondary hypogonadism. J Urol. 1996;155:529-33.

Schopohl J, Mojto J, Losa M, et al. Changes in anterior pituitary response in patients with idiopathic hypothalamic hypogonadism caused by pulsatile GnRH therapy and testosterone replacement. Exp Clin Endocrinol Diabetes. 1995;103:84-90.

Metyolkina L, Peresedov V. Transnasal stereotactic surgery of pituitary adenomas concomitant with acromegaly. Stereotact Funct Neurosurg. 1995;65:184-86.

FROM THE INTERNET
Froehlich or Frölich Syndrome. nd. 1p.
www.vulgaris-medical.com/testf/frolich.htm

Adiposogenital dystrophy Information Page(s). Last Update; 1 Mar 2003:4pp.
www.diseasedatabase.com/sieve/item1.asp?glngUswerChoice=29318

Pituitary-Hypothalamic Syndromes. nd. 2pp.
www.pathguy.com/lectures/pituitar.htm