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SUMMARY The effect of glucose or insulin administration in a group of five patients with partial lipodystrophy and three with total lipodystrophy was studied. In only one patient was the glucose tolerance curve abnormal. Mean fasting serum insulin, growth hormone, free fatty acids (FFA) and triglycerides were all significantly elevated. The serum insulin response to glucose was grossly elevated. Insulin resistance was present. The serum insulin was shown to be immunologically normal, Exogenous insulin disappeared at a normal rate from the circulation, suggesting that the elevated insulin levels in the fasting state and after glucose were due to hypersecretion. Serum growth hormone levels failed to suppress normally after glucose. Serum FFA fell after glucose or insulin administration. In one patient treated with propranolol unusual insulin responses to the administration of glucose were observed. A working hypothesis capable of explaining the metabolic changes in lipodystrophy is proposed.

SUMMARY A 46XY individual with incomplete male pseudohermaphroditism was studied. The phenotype was distinctive, with a masculine habitus despite a small phallus, gynaecomastia and diminished virilization. Plasma levels of testosterone, oestrogens, gonadotrophins and sex-hormone binding globulin were elevated. It is proposed that this syndrome is a variant of Type I incomplete male pseudohermaphroditism.

SUMMARY Basal free fatty acid (FFA) turnover was found to be elevated or at the upper limit of normal in a patient with total lipodystrophy. The decrease in plasma FFA concentration which occurred after intravenous administration of insulin was shown to be primarily due to a fall in the inflow of FFA into the circulation. These results provide support for the suggestion that adipocytes in total lipodystrophy are able to synthesize triglyceride, but that they are unable to store it because of rapid lipolysis.

SUMMARY Eight patients with treated Addison's disease were studied whilst receiving different doses of fludrocortisone together with a constant intake of glucocorticoid. Plasma renin activity (PRA), blood pressure, pulse rate and plasma potassium and urea concentrations were measured after 2-week periods on each dose. In two patients, PRA measurements indicated that mineralocorticoid replacement therapy had been inadequate. In four others, PRA remained normal throughout the study, even after fludrocortisone had been discontinued, suggesting that the drug was unnecessary for the maintenance of normal sodium balance in these patients. Asymptomatic fludrocortisone overdosage was indicated by a low plasma potassium concentration, but not by PRA measurements which failed in this study to distinguish between adequate and excessive mineralocorticoid replacement.

SUMMARY A patient with partial lipodystrophy is described in whom hypertriglyceridaemia was accompanied by marked hyperinsulinaemia. The hyperlipidaemia was due to increased plasma levels of very low density lipoprotein (VLDL). Kinetic studies, performed after injection of autologous radioiodinated VLDL, indicated that the raised VLDL levels were associated with over-production of this lipoprotein. Administration of diazoxide led to a substantial fall in serum insulin levels, accompanied by reduction in VLDL production and in serum triglyceride concentration. The possible role of insulin in inducing hyperlipidaemia by causing over-production of VLDL is discussed.

SUMMARY The production of ACTH, gastrin and glucagon by a pancreatic islet cell tumour is reported. The tumour contained at least two distinct cell types on electron microscopy. The fulminating hypercorticism was efficiently controlled with metyrapone and aminoglutethimide, but streptozotocin was not an effective anti-tumour agent.