Contralateral adrenal suppression on adrenocortical scintigraphy provides good evidence showing subclinical cortisol overproduction from unilateral adenomas.

Unilateral and/or predominant uptake on adrenocortical scintigraphy (ACS) may be related to autonomous cortisol overproduction in patients with subclinical Cushing's syndrome (SCS). However, there is no information regarding whether increased tracer uptake on the tumor side or decreased uptake on the contralateral side on ACS is more greatly associated with inappropriate cortisol production. Therefore, we evaluated the relationship between quantitative 131I-6ß-iodomethyl-norcholesterol (131I-NP-59) uptake in both adrenal glands and parameters of autonomic cortisol secretion and attempted to set a cut off for SCS detection. The study included 90 patients with unilateral adrenal adenoma who fulfilled strict criteria. The diagnosis of SCS was based on serum cortisol ≥3.0 µg/dL after 1-mg dexamethasone suppression test (DST) with at least 1 other hypothalamus-pituitary-adrenal axis function abnormality. Twenty-two (27.7%) subjects were diagnosed with SCS. The uptake rate on the affected side in the SCS group was comparable to that in the non-functioning adenoma group. In contrast, the uptake rate on the contralateral side was lower and the laterality ratio significantly higher in the SCS group. The two ACS indices were correlated with serum cortisol levels after a 1-mg DST, but uptake on the tumor side was not. Tumor size was also important for the functional statuses of adrenal tumors and NP-59 imaging patterns. The best cut-off point for the laterality ratio to detect SCS was 3.07. These results clearly indicate that contralateral adrenal suppression in ACS is good evidence showing subclinical cortisol overproduction.

Primary malignant hepatic glucagonoma: an autopsy case.

A 73-year-old woman was admitted to our department for treatment of diabetes (plasma glucose 289 mg/dl, HbA(1C) 7.1%, and glycated albumin 34.9%). She displayed the signs and symptoms of glucagonoma syndrome, including necrolytic migratory erythema (NME), low aminoacidemia, and a marked increase of the serum glucagon level (4,940 pg/ ml). Thus, we suspected a glucagonoma causing secondary diabetes. However, we could not detect any mass in the pancreas or the gastrointestinal tract, and only found a liver lesion resembling a hemangioma. Her NME improved markedly after intravenous infusion of amino acids, and her plasma glucose was controlled reasonably well by intensive insulin therapy. However, her general condition deteriorated and she died on day 57 after hospitalization. At autopsy, the only tumor detected was the liver mass. This was a large solid tumor (8 x 6 x 5 cm) with a pattern of white and dark brown stripes located in the left lobe, while two white nodules were also found in the right lobe. Based on the histopathological and immunohistochemical findings, the liver lesion was shown to be a malignant glucagonoma with intrahepatic metastases. Since primary malignant hepatic glucagonoma has not been reported before, we present this extremely rare case of primary malignant glucagonoma of the liver.

No ghrelin response to oral glucose in diabetes mellitus with gastroparesis.

To investigate the role of ghrelin, an endogenous ligand of the growth hormone secretagogue receptor, in diabetic gastroparesis, we evaluated the plasma ghrelin profile during the oral glucose tolerance test in 55 patients with diabetes (men/women: 36/19, mean +/- SE of age: 55.1 +/- 1.7 years) with or without gastroparesis (diagnosed by the (13)C-acetate breath test). We also further examined cardiac autonomic neuropathy by assessing 24-hour variation of the R-R interval in randomly selected 32 patients with diabetes (men/women: 23/9, mean +/- SE of age: 54.2 +/- 2.5 years), and evaluated the influence of autonomic neuropathy on ghrelin. The fasting plasma ghrelin level was significantly lower in diabetes mellitus with gastroparesis than in healthy controls (7.9 +/- 0.7 fmol/ml versus 16.6 +/- 5.3 fmol/ml, p = 0.006). Patients with diabetes with gastroparesis showed no decrease of plasma ghrelin after glucose loading, unlike patients without gastroparesis or healthy controls. Diabetes mellitus with autonomic neuropathy, but not those without it, also showed no decrease of plasma ghrelin after glucose loading. Diabetic gastroparesis may be related to ghrelin-associated neurohormonal abnormalities, but the pathophysiological meaning of this abnormal ghrelin response needs further clarification.

Penile necrosis by calciphylaxis in a diabetic patient with chronic renal failure.

The patient was a 41-year-old man who had suffered from diabetes for 24 years and had been on insulin therapy for 17 years. The patient had commenced hemodialysis in 1999. Some of his toes on both feet had been amputated in 2000 due to diabetic gangrene. The patient was admitted to our hospital in early March 2005 complaining of a painful ulcer on the tip of the penis. At the time of admission, multiple ulcers and necrosis were observed on the prepuce and penis, as well as an ulcer on the left foot and gangrene of the left great toe. Imaging studies demonstrated severe arteriosclerosis with calcification of both large and small arteries. After penile amputation was performed because of severe pain, the wound became ulcerated, and a rectal ulcer as well as skin ulcers also developed in the bilateral inguinal regions. The penile necrosis, skin ulcers, and rectal ulcer were thought to have been caused by calciphylaxis. Calciphylaxis is a disorder in which necrosis occurs at sites of arterial obstruction and calcification, and the prognosis is poor. Seventeen patients with penile necrosis due to calciphyalxis, including our patient, have been reported in Japan. They all had a long history of diabetes, and 15 of the 17 patients were on dialysis.

Discrepancies in results of low-and high-dose dexamethasone suppression tests for diagnosing preclinical Cushing's syndrome.

According to the diagnostic criteria for adrenal preclinical Cushing's syndrome (PreCS) established by a group headed by the Ministry of Health, Labor and Welfare (MHLW), low- and high-dose dexamethasone suppression tests (DSTs) must be performed to prove autonomous cortisol secretion, i.e., > or =3 microg/dL serum cortisol following 1-mg DST administration, and > or =1 microg/dL serum cortisol following 8-mg DST administration. However, discrepancies have been documented in the results of low-and high-dose DSTs. We therefore investigated the validity of the DST for diagnosing PreCS by performing 1-mg and 8-mg DSTs in 39 patients with adrenal incidentaloma, but no characteristic Cushingoid symptoms. In about half of these patients (20/39, 51.3%), high-dose DST was positive but low-dose was negative, and one or more of the other abnormalities of hypothalamus-pituitary-adrenal axis dysfunction was seen in 75% of these patients. Furthermore, no significant difference in incidence of glucose intolerance and hypertension was noted in patients with positive high-dose DST and negative low-dose DST compared with patients with positive low- and high-dose DST. Under the current MHLW diagnostic criteria, patients with positive high-dose DST and negative low-dose DST are not diagnosed with PreCS, but some of these patients should be. Discrepancies in the results of low- and high-dose DSTs appear attributable to the current cutoff values, and further investigations are necessary to resolve these discrepancies.