Acanthosis nigricans-muscle cramps-acral enlargement syndrome

Acanthosis nigricans-muscle cramps-acral enlargement syndrome, also known as Acanthosis nigricans-insulin resistance-muscle cramps-acral enlargement syndrome is an extremely rare genetic disorder which is characterized by the appearance of acanthosis nigricans, insulin resistance, muscle cramps of severe intensity, and acral hypertrophy/enlargement.[1][2][3] Only 2 cases have been reported in medical literature.

Acanthosis nigricans-muscle cramps-acral enlargement syndrome
Other names	Acanthosis nigricans-insulin resistance-muscle cramps-acral enlargement
Specialty	Medical genetics
Symptoms	Kidney enlargement, localized cutaneous hyperpigmentation, insulin resistance, muscle cramps, and polycystic ovary syndrome (in women)
Usual onset	Birth
Duration	Life-long
Causes	Autosomal recessive inheritance
Prevention	none
Medication	Dilantin
Prognosis	Good to Ok
Frequency	very rare, only 2 cases known to medical literature

It was first discovered when Jeffrey Flier and his colleagues described two siblings of the opposite sex with the symptoms mentioned above. (plus: large, chunky hands), the sister had virilized polycystic ovaries.[4] After being treated with dilantin, the cramps' severity lowered and the brother's insulin resistance also lowered.[5][6] The inheritance pattern of this disorder is thought to be autosomal recessive.[7]