Summitt syndrome
Overview
A very rare genetic disorder abnormalities of the head, hands and feet as well as obesity.
Symptoms
* Cone-shaped skull * Irregularities on back of skull * Epicanthal folds * Crossed eyes * Narrow palate * Delayed teeth eruption * Syndactyly * Knock-knee * Obesity * Enlarged male breasts
Causes
* Exogenous obesity (most common) –No demonstrable disease as the cause –Excessive weight gain from imbalance between caloric intake and energy expenditure –Linear growth is robust and frequently accelerated * Hormonal causes –Associated with poor linear growth –Hypercortisolism: Cushing syndrome is any type of glucocorticoid excess (endogenous or exogenous); Cushing disease describes pituitary ACTH overproduction –Hypothyroidism –Growth hormone deficiency * Insulinoma * Hypothalamic obesity –Tumors (e.g., craniopharyngiomas) –Following neurosurgery or irradiation –Head trauma –Infiltrative/inflammatory * Genetic syndromes –Prader-Willi syndrome –Laurence-Moon-Bardet-Biedl syndrome –Alström syndrome –Cohen syndrome –Down syndrome –Carpenter syndrome –Grebe syndrome –Beckwith-Wiedemann syndrome o Defects in metabolic/eating regulatory pathways is an area of intense investigation; multiple mutations are theoretically possible, but only a few have actually been discovered in humans –Congenital leptin deficiency (extremely rare) –Leptin resistance (more common than deficiency) o Drugs –Chronic glucocorticoids –Neuropsychotropic medications o Adiposogenital dystrophy syndrome
Diagnosis
Routine laboratory tests include a CBC, urinalysis, chemistry panel, 2-hr postprandial blood sugar, and thyroid profile. If an insulinoma is strongly suspected, a 24- to 36-hr fast, a 5-hr glucose tolerance test, and tolbutamide tolerance test may be done. If Cushing's syndrome is suspected, a serum cortisol and cortisol suppression test should be done. Pelvic ultrasound will help diagnose polycystic ovaries. Chromosomal analysis will help diagnose Klinefelter's syndrome. Perhaps a psychiatrist should be consulted.
Treatment
* If syndrome or no known disease as etiology –Nutritional education and diet manipulation –Exercise regimen (energy expenditure must exceed intake) –Behavior modification involving family * Hormonal etiology –Hormone replacement for hypothyroidism or growth hormone deficiency –Surgical intervention if hypercortisolism caused by tumor –Decrease exogeneous glucorticoids if not medically contraindicated * Leptin treatment in leptin deficiency (therapeutic trials) * If patient also has type II diabetes mellitus, insulin or oral medications may be required in addition to improved diet and exercise