Launois Syndrome

Gigantism caused by excessive GH secretion usually because of a pituitary adenoma that normally occurs before the epiphyses are fused in comparison with acromegaly that occurs after fusion of the epiphyses.

Acromegaloid Gigantism; Fractional Hypopituitarism-Gigantism Syndrome; Neurath-Cushing Syndrome; Pituitary Gigantism; Launois-Bensaude Syndrome.

Very rare cause of tall stature in children. Reports are limited to sporadic cases. Peak incidence in teenagers, although it has been reported in a child as young as 21 months.

Not a genetic syndrome.

Almost always caused by pituitary adenoma, producing excessive GH. Some tumors are mixed and produce both prolactin and GH. Very rarely it is caused by excessive secretion of GH-releasing factor from an ectopic source.

Rapid linear growth, tall stature, large hands and feet, coarsening of facial features, prognathism, macroglossia, widely spaced teeth, and husky voice. Other features include greasy thick skin, slipped epiphyses with joint pain, kyphoscoliosis, myopathy, nerve entrapment syndromes; headaches and visual field defects, usually hemianopsia, pale optic discs and optic atrophy. Patients may have behavioral problems and mental retardation, early pubertal signs, galactorrhea, glucose intolerance, obesity, or diabetes mellitus.

Clinical features; biochemical (elevated serum levels of GHs not suppressed by oral glucose loading, elevated levels of IGF-1, high prolactin and gonadotropin levels); radiology (advanced bone age, enlarged sella turcica on skull radiograph, CT scan demonstrates pituitary tumor).

May be anxious and uncooperative in the presence of visual defects, mental retardation, or behavioral problems. Airway problems should be anticipated, but, unlike acromegaly, glottic stenosis and vocal cord paresis have not been reported in gigantism. Presence of myopathy may predispose to postoperative respiratory insufficiency. Close monitoring of preoperative glucose level necessary in the presence of diabetes mellitus. If the patient is already being treated, complications of medical and/or irradiation therapy, such as pituitary insufficiency, should be evaluated preoperatively.

Acromegaly: Hormonal disorder caused by overproduction of GH in adults, not resulting in gigantism but enlargement of extremities, usually a result of a benign tumor of the pituitary gland.