MAG and hyperinsulinemic hypoglycemia, familial, 4: Associated findings include pseudoxanthum elasticum in 2 patients [44,45], peripheral neuropathy with the presence of monoclonal IgM with anti-MAG (myelin-associated glycoprotein) in 1 patient [46], C4 deficiency in 2 patients [42] and nodular regenerative hyperplasia of the liver in 1 patient [47], impairment of renal function in 1 patient [48], thrombophilia with anti-phospholipid antibodies and hyperhomocysteinemia [49] and hearing loss [3].