A number of patients with aseptic necroses of bone and hyperlipoproteinemia of types II and IV after Fredrickson are reported on. More than one half of them had hyperuricemia without symptoms of gout. The relationship between fat-, purine- and carbohydrate-metabolism are discussed. The clinical pictures of hyperuricemia, gout and hyperlipoproteinemia are shown to resemble each other. Differential diagnosis, particularly as related to aseptic necroses of bone, is discussed in detail.