PIK3CA and hypoinsulinemic hypoglycemia and body hemihypertrophy: Such variants are often overactivating variants of the phosphoinositide-3-kinase/protein kinase B/mammalian target of rapamycin pathway (PI3K/AKT/mTOR) (pathogenic variants in PIK3CA in PROS, KTS; mutations of AKT1 in PS, of AKT2 in hypoinsulinemic hypoglycemia with hemihypertrophy (HIHGHH), of mTOR in Smith-Kingsmore syndrome (SKS)) or deactivating variants in repressors of this pathway (the phosphatase and tensin homolog (PTEN) in PHTS and PS) (Yehia et al., 1993).