The 24-hour effects of glyburide and chlorpropamide after chronic treatment of type II diabetic patients.

A single-blind, randomized, comparative evaluation of glyburide (GL) and chlorpropamide (CP) therapy was performed in twenty previously untreated patients with non-insulin dependent diabetes mellitus (NIDDM) of about two years duration. Only newly diagnosed patients who were never treated and whose fasting blood glucose (FBS) levels were greater than 140 mg/dl after a six to eight week trial of dietary restriction were evaluated. Metabolic studies were performed before and after four months of therapy. GL and CP produced essentially the same effects on serum levels of glucose, insulin, glucagon (IRG), growth hormone (GH), cholesterol, and triglyceride. The mean 24-hour glucose levels for both the GL and CP groups were significantly lower than the pretherapy values (p less than 0.001). The mean 24-hour insulin levels did not change significantly during therapy (p greater than 0.05). Excellent control of plasma glucose was possible during the entire day without producing nocturnal hypoglycemia. Neither GL nor CP therapy influenced the mean 24-hour levels of IRG, GH, or cholesterol. However, mean 24-hour levels of triglyceride were lower in both groups. IRG levels were elevated and the pattern of change in the insulin and IRG levels paralleled each other, which suggested that glucagon may play a role in the resistance of insulin action in NIDDM. GH levels were normal and remained unchanged during therapy. It was concluded that detailed 24-hour studies are important for better understanding the spectrum of abnormalities in newly diagnosed patients with NIDDM who were never treated.(ABSTRACT TRUNCATED AT 250 WORDS)

Giant pheochromocytoma with sarcoidosis.

We describe a case of an asymptomatic patient with a huge left abdominal mass, which at operation was found to be a cystic pheochromocytoma weighing over 3,000 gm. A dignosis of sarcoidosis was established simultaneously, with the discovery of sarcoid granulomas in abdominal nodes and within the tumor mass itself. This is only the second observation of coexistent sarcoidosis and pheochromocytoma, and with the paucity of related literature, we conclude the association is probably fortuitous.

Prolactin-secreting pituitary adenomas in multiple endocrine adenomatosis, type I.

In three unrelated families, four patients with multiple endocrine adenomatosis, type I, had confirmed or highly probable prolactin-secreting pituitary adenomas. In one patient, selective transsphenoidal tumor resection resulted in normal prolactin levels and resumption of menses. Heretofore, the majority of pituitary tumors in such patients had been thought to be nonsecreting chromophobe adenomas, but recent studies have shown that, in sporadic cases, as many as three fourths of "nonsecreting" pituitary tumors in fact secrete prolactin. Thus, based on our experience and reports of others, we believe that prolactin-secreting tumors may be common in patients with pituitary tumors as part of the syndrome of multiple endocrine adenomatosis, type I, and we recommend that serum prolactin be measured when evaluating these patients and their families.

Feedback-controlled dextrose infusion during surgical management of insulinomas.

Through the use of a feedback-controlled dextrose infusion system, we obtained continuous monitoring of the blood glucose level in a patient undergoing surgery for multiple pancreatic beta-cell tumors. In addition, this device infused dextrose at variable rates to maintain a predetermined euglycemic level of 90 mg/dl. Before locating the source of excessive insulin production, the maximum dextrose infusion rate of 400 mg/min was required; but after extirpation of multiple insulinomas, the dextrose-infusion rate declined whereas the blood glucose level rose above the preselected level. These results emphasize the usefulness of a monitoring and infusion system not only in protecting the patient from the hazard of hypoglycemia under anesthesia but also as an aid in determining whether all insulin-secreting tumors have been removed.

Intrasellar cysticercosis presenting as a pituitary tumor: successful transsphenoidal cystectomy with preservation of pituitary function.

A 42-year-old woman from El Salvador presented with arthralgias and headache. She was found to have an enlarged sella with an intrasellar mass. Transsphenoidal exploration of the sella revealed a cysticercus. The cyst was removed and normal pituitary function was retained. Review of the literature showed three previously reported confirmed or suspected cases of intrasellar cysticercosis: in two, the diagnosis was made at autopsy; in the third, a patient with hypopituitarism, intrasellar cysticercosis was suspected in life but never confirmed histologically. Transsphenoidal cystectomy successfully treated our patient without compromise of pituitary function and is recommended for similar cases.

Diabetes mellitus following rodenticide ingestion in man.

Ketotic, insulin-requiring diabetes mellitus and a severe peripheral neuropathy developed in a previously healthy 25-year-old man several days after he attempted suicide with rat poison containing N-3-pyridylmethyl N'-p-nitrophenyl urea. Study of islet-cell function ten months after ingestion showed a reduced disappearance rate of intravenous glucose and depressed C-peptide response to intravenous glucose when compared with a normal control but no impairment of glucagon release after intravenous arginine stimulation. Nerve conduction studies demonstrated severe sensory and mild motor neuropathy. Quadriceps capillary basement membrane thickness was in the diabetic range. Because at least 15 similar occurrences have been reported to the manufacturer, this agent appears to be diabetogenic in man, probably causing beta-cell destruction. Niacinamide, which can prevent glucose intolerance in both streptozocin- and alloxan-treated animals and prevents death in rats given this rodenticide, may be a useful antidote.