Synonym: glucagon cell adenomatosis
Inheritance: autosomal recessive
Features:
(1) elevated serum glucagon concentration (hyperglucagonemia)
(2) absence of glucagonoma
(3) glucagon (alpha) cell hyperplasia and/or glucagon cell adenomatosis
(4) biallelic-inactivating mutations in the gene GCGR (gene for the glucagon receptor at 17q25.3)
If glucagon receptors are functional, then the patient will show hyperglycemia and rash.
If glucagon receptors are nonfunctional, then the patient will not show the rash and may have hypoglycemia and elevated serum amino acids (arginine, citrulline, cystine. glycine).
Complications:
(1) development of glucagonoma
(2) abnormal blood glucose concentrations
