Makoto Imamura

Hypoglycemia due to nateglinide administration in diabetic patient with chronic renal failure

A 56-year-old woman with diabetic triopathy, rheumatoid arthritis and chronic renal failure was admitted for severe hypoglycemic coma. Arthralgia had been deteriorating for 6 months. Therefore, 5 mg of prednisolone was administered. Postprandial blood glucose (PPG), however, elevated from 260 to 290 mg/dl, although fasting blood glucose (FBG) levels ranged from 80 to 110 mg/dl. Three months after, 270 mg of nateglinide was given in addition to acarbose. After 2 days, hypoglycemia occurred at 02:00 h. Nateglinide was then decreased to 180 mg (before breakfast and lunch). After 5 days, hypoglycemia re-occurred at 01:00 h. Nateglinide was subsequently decreased to 90 mg before breakfast. The PPG levels ranged from 130 to 150 mg/dl. Hypoglycemia did not occur during the next 2 months. On admission, FBG; 59 mg/dl, fasting immunoreactive insulin; 34 microU/ml, indicated hyperinsulinemic hypoglycemia. We administered 20 g of glucose intravenously, however, hypoglycemia recurred 4 times and 20 g of glucose was then administered. Although the plasma nateglinide level decreased, the nateglinide metabolite, N-[trans-4-(1-hydroxy-1methylethyl)-cyclohexanecarbonyl]-D-phenylalanine levels still had not decreased 29 h after nateglinide administration. Therefore, chronic renal failure appeared to alter the pharmacokinetic parameters of the nateglinide metabolite, which had accumulated by chronic renal failure. The nateglinide metabolite caused severe hypoglycemia in this case.

Insulinoma accompanied by diabetes mellitus

A 53-year-old type 2 diabetic man was admitted due to spontaneous relatively hyperinsulinemic hypoglycemia. Oral glucose ingestion and arginine tolerance test showed hyperinsulinemic response. Arterial stimulation and venous sampling (ASVS) showed hyperinsulinemic response measured from the splenic artery after calcium gluconate stimulation. Diagnosis was insulinoma in the pancreas feeding from the artery. He has not suffered from spontaneous hypoglycemia since removal of the pancreatic body, tail and spleen. The specimen showed a solitary islet cell tumor. The high homeostasis model assessment of insulin resistance (HOMA-R) levels reflecting insulin resistance and hyperinsulinemic response after operation remained almost unchanged, indicating high insulin resistance and an insulin hypersecreting diabetic patient.

Sex and age differences in soluble guanylate cyclase activity in human platelets

Soluble guanylate cyclase is a key enzyme of nitric oxide (NO)-related intracellular signal transduction in platelets. In the present study, we investigated the effects of sex and age on the enzyme activity in human platelets. Soluble guanylate cyclase activity was determined by generation of cyclic GMP in platelet cytosol. No significant differences in the basal activity of soluble guanylate cyclase were observed between in men and women, and between in young and old subjects. However, soluble guanylate cyclase activity in response to sodium nitroprusside, an exogenous NO donor, was higher in young men than in young and old women. Furthermore, the enzyme activity was lower in old than in young men, but there were no differences in female platelets between from young and old subjects. The present data suggest that NO-related signal transduction system in the platelet is affected by sex and age, which, to certain extent, contributes to different sensitivity of human platelets.

A Case Report of a Diabetic Nephropathy Patient With Cirrhotic Ascites Treated by Peritoneal Dialysis

Abstract:  A 64‐year‐old man was admitted because of abdominal fullness, edema and anorexia. He had come to our hospital for treatment of liver cirrhosis and diabetic nephropathy for 1 year. We started diuretics and human albumin intravenous administration. Although the edema disappeared and abdominal fullness improved a little, blood urea nitrogen (BUN) and serum creatinine became elevated, hepatic function deteriorated and he lost his appetite. We consequently started continuous ambulatory peritoneal dialysis (CAPD) in order to control ascites and uremia. Abdominal fullness, appetite and BUN and serum creatinine improved without hepatic function deterioration. It might be important to start CAPD to control ascites although serum creatinine levels might be slightly elevated.