Recent reports on Hashimoto’s thyroiditis (HT) with increased numbers of IgG4-positive plasma cells suggest that this type of HT may have a close relationship to IgG4-related disease (IgG4-RD). This unique subgroup of HT is termed as IgG4 thyroiditis and reveals distinct clinical, serological, and sonographic features from the non-IgG4 thyroiditis group. On the basis of immunostaining for IgG4, HT was divided into an IgG4 thyroiditis group and a non-IgG4 thyroiditis group. Clinically, IgG4 thyroiditis was associated with younger age group, lower female-male ratio, higher levels of thyroid autoantibodies, diffuse low echogenicity, more rapid progress requiring surgical treatment and more subclinical hypothyroidism. Serum IgG4 concentrations elevated in IgG4 thyroiditis and decreased significantly after a thyroidectomy. Histopathologically, IgG4 thyroiditis showed a higher grade of stromal fibrosis, lymphoplasmacytic infiltration, and follicular cell degeneration than non-IgG4 thyroiditis. IgG4 thyroiditis may represent IgG4-RD of thyroid gland, because it shares common histopathological characteristics with IgG4-RD in other organs. The identification of IgG4-RD of the thyroid gland opens new insights not only for patient’s treatment with HT but also for the development of new therapeutic approaches for this rapidly progressive destructive subtype of HT. This article mainly focuses on reviewing the unique histopathological, clinical, and serological features of IgG4 thyroiditis group of HT. The etiology and genetic changes of HT are also discussed.

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Late-night salivary cortisol (NSC) has been recognized as a sensitive and easy-to-perform screening test for the diagnosis of overt Cushing’s syndrome (CS). However, there have been few reports on the diagnostic utility of salivary cortisol (SC) measurement in the diagnosis of subclinical Cushing’s syndrome (SCS). Therefore, the present study was designed to evaluate the usefulness of SC measurements at late-night and after overnight 1 mg dexamethasone suppression test (DST) for the diagnosis of SCS in 42 patients with adrenal incidentaloma. We evaluated 16 patients with SCS, 12 with nonfunctioning adenoma (NFA), 8 with primary aldosteronism (PA), and 6 with pheochromocytoma (Pheo). NSC levels in SCS patients (0.238 ± 0.106 μg/dL) were significantly (P < 0.05) higher than those in NFA patients (0.154 ± 0.104 μg/dL); the cutoff value (0.11 μg/dL) by ROC analysis gave high sensitivity (100%) with low specificity (50%). Post DST SC levels in SCS patients (0.238 ± 0.116 μg/dL) were significantly (P = 0.0081) higher than those in NFA patients (0.136 ± 0.110 μg/dL); the cutoff value (0.12 μg/dL) by ROC analysis gave high sensitivity (93.8%) with somewhat improved specificity (58.3%). Both NSC and post DST SC levels were comparable between NFA, PA, and Pheo patients. In conclusion, our study revealed that measurements of NSC and/or post DST SC among patients with adrenal incidentaloma prove to have high sensitivities, but low specificities for the diagnosis of SCS from NFA, suggesting its possible alternative option before the screening tests for SCS currently employed in Japan.

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Hirsutism is characterized by excessive growth of terminal hair in a male pattern. Idiopathic hirsutism (IH) is a common cause of hirsutism. Since there are few data demonstrating IH is associated with insulin resistance, we tried to assess various insulin sensitivity indices in lean IH and compare with healthy subjects. A cross-sectional study was performed in 71 lean (BMI between 20-25 kg/m²) women (17-39 years old), 31 with IH and 40 healthy individuals. Blood glucose, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), hepatic insulin sensitivity (ISI _HOMA), Quicky index, reciprocal fasting insulin resistance index, fasting Belfiore index, and fasting glucose/insulin ration (GIR) were estimated using a single fasting sample of glucose and insulin levels. Raynaud indices calculated using the mathematical estimation in a single fasting sample of insulin levels were determined and compared in two groups. Fasting insulin, Raynaud index, HOMA-IR and Fasting insulin resistance index (FIRI) results were higher in IH group than in controls (p<0.01, for all). Fasting Belfiore index, QUICKI index, ISI _HOMA and FIRI^-1 results were lower in IH group than in controls (p<0.01, for all). Our study showed that lean IH patients were more insulin resistant than healthy subjects. We propose that insulin sensitivity indices are useful methods for measuring insulin resistance in IH.

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We prospectively examined the additional effects of highly purified eicosapentaenoic acid (EPA) particularly on the vascular function of diabetic patients with hypercholesterolemia receiving statin therapy. We enrolled 28 patients with type 2 diabetes complicated by dyslipidemia who had been treated with statins for at least one year. The patients were randomly assigned to 2 groups: administration of statin alone (group S: n = 13) and addition of EPA to the current statin therapy (group SE: n = 15). The highly purified EPA was administered at a dose of 1,800 mg/day for 6 months. To evaluate vascular function, the duration of reactive hyperemia (DRH), which is the time required for forearm blood flow to return to the basal level after inducing reactive hyperemia, was measured using strain gauge plethysmography. There were no significant differences in the clinical background factors between the 2 groups. Low-density lipoprotein cholesterol (LDL-C), and non-high-density lipoprotein cholesterol levels significantly decreased after 6 months only in group SE. Compared with the baseline data, no significant change in DRH was observed after 6 months in group S. By contrast, DRH was significantly prolonged after 6 months in group SE, indicating that the addition of highly purified EPA improved vascular function. Our results showed that in patients with type 2 diabetes and receiving statin therapy whose LDL-C level was less than 100 mg/dL, the addition of highly purified EPA for 6 months significantly improved vascular function.

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Central compartment lymph node (CCLN) management in patients without clinical or radiologic evidence of CCLN metastasis is debatable. The aim of the present study was to evaluate outcomes of surgery for papillary thyroid microcarcinoma (PTMC) with prophylactic ipsilateral CCLN dissection (PI-CCND) in a large cohort of patients treated at one single institution in a 5-year follow-up. Between January 2000 and December 2005, 2192 patients with papillary thyroid carcinoma underwent thyroid surgery. Inclusion criteria were patients with PTMC, absence of clinical or radiologic evidence of CCLN metastasis, and a follow-up for a period ≥60 months. Data from 842 patients were retrieved in the current retrospective cohort study. PI-CCND was routinely performed in addition to thyroid surgery in all cases. Ipsilateral CCLN metastasis was found in 218 patients (25.9%). Postoperative complications included 76 cases of transient hypoparathyroidism (9%), 11 cases of permanent hypoparathyroidism (2.6%), four cases of vocal cord palsy (0.5%), and one case of bleeding (0.1%). Univariate analysis and multivariate logistic regression analysis revealed that CCLN metastasis was statistically significantly correlated with tumor size and extracapsular invasion. Recurrence has been observed to date in 19 patients (2.26%). No CCLN site recurrence occured in patients who underwent PI-CCND. This study demonstrates the technical feasibility and safety of PI- CCND, which is a better way to determine lymph node status for a more accurate staging of disease and risk stratification. PI-CCND should be considered even if clinical or radiological exams are negative for CCLN metastasis.

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Pregnancy in acromegalic patients is a rare event, but is usually uneventful, with stable GH and IGF-I levels and no tumor enlargement. Medical treatment can usually be withdrawn without problems and although no major adverse event has been reported, the suspension of drug treatments is generally recommended. No case report exists in the literature regarding evolution of a somatotropinoma with invasiveness markers throughout pregnancy. We report a case of an acromegalic patient who was submitted to surgery and treated with octreotide LAR maintaining a stable residual tumor and an IGF-I close to the normal levels. Her tumor presented with a high Ki-67 (11.6%) and a low aryl hydrocarbon receptor-interacting protein (AIP) expression. When she became pregnant, octreotide LAR was withdrawn, and despite remaining asymptomatic during pregnancy, tumor growth occurred with compression of surrounding structures. In conclusion, pregnancy in acromegalic patients has usually a favorable prognosis with no tumor growth. However, in the presence of high Ki-67 labeling index and low AIP expression, tumor enlargement may occur and somatostatin analogue treatment throughout the pregnancy should be considered.

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Hypogonadism is a clinical condition that occurs due to infrequent abnormalities in the hypothalamic-pituitary-gonadal (HPG) axis in adolescence. Symptoms include weakening of muscle and bone strength. 30 young male patients with congenital hypogonadotropic hypogonadism (CHH) and 20 healthy young males were included in the present study. Quadriceps and hamstring muscle strength, balance and anaerobic performance capacities of the study group were measured both before and six months after Testosterone replacement therapy (TRT). The strength of the extensor and flexor muscles of both legs showed a statistically significant increase in the isokinetic test values at 60⁰/sec and 180⁰/sec angular velocity (p < 0.05). When the parameters related to balance were investigated, a statistically significant difference was found for stability indices of left and right between pre-TRT and post-TRT (p = 0.001 for both comparisons). According to the patients’ anaerobic performance measurement results, a statistically significant improvement (p < 0.001) was also found between pre-TRT and post-TRT values for each parameter. It was shown that TRT significantly increases muscle strength, balance, and anaerobic performance of patients with male CHH. As a result, we absolutely recommend the use of TRT in patients with male CHH.

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Dipeptidyl peptidase-4 (DPP-4) inhibitors are a newer class of oral hypoglycemic agents for the management of diabetes that elevate the plasma concentration of active glucagon-like peptide-1 via inhibition of DPP-4. They effectively lower not only glycosylated hemoglobin levels, but also fasting and postprandial plasma glucose levels. Patients with diabetes occasionally consume an overdose of oral hypoglycemic agents in suicide attempts: the prevalence of depression is high in patients with diabetes, and depression is a strong risk factor for suicide. We encountered an 86-year-old woman with type 2 diabetes and depression, who was transferred to the emergency room 4h after ingestion of 1,700 mg of the DPP-4 inhibitor sitagliptin (1,700 mg is 17 times greater than the approved maximum dose). Upon arrival, she was fully conscious, plasma glucose was 124 mg/dL, and serum immunoreactive insulin level was 5.81 μU/mL. Thereafter, the plasma concentration of sitagliptin rose to 3,793 nM, which is 4.5 times higher than the value found under regular treatment with the maximum dose. The patient did not suffer from hypoglycemia, suggesting that a single oral overdose of sitagliptin is unlikely to cause hypoglycemia. A literature review of oral anti-diabetic agents revealed that overdose of biguanides is occasionally fatal when immediate intensive care is not provided. In summary, sitagliptin is a good treatment option for diabetic elderly patients or patients with psychiatric disorders who are suicidal and do not require insulin.

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Emerging evidence has indicated that insulin-like growth factor binding protein-2 (IGFBP-2) may be involved in the development of obesity and insulin resistance like IGFBP-1. The aim of this study was to measure serum IGFBP-2 levels in overweight and obese children and to compare these levels with those of controls. We also analyzed the associations between IGFBP-2 and insulin sensitivity indices and cardiovascular risk factors. 134 Korean children including 55 overweight and 59 obese subjects were enrolled. We measured anthropometric values and determined fasting serum levels of IGFBP-2, glucose, insulin, lipid profiles, and insulin sensitivity indices including the homeostatic model assessment of insulin resistance (HOMA-IR) and the Quantitative Insulin Sensitivity Check Index (QUICKI). The subjects were subgrouped based on body mass index (BMI) and pubertal stage, and association analyses between IGFBP-2 levels and measured factors were performed in each group. Serum IGFBP-2 levels in overweight or obese children were significantly lower than those of controls regardless of pubertal development. Serum IGFBP-2 levels were negatively correlated with weight, BMI, waist circumference, fasting insulin levels, and HOMA-IR but were positively correlated with QUICKI. The associations were stronger in pubertal children than those in prepubertal children. However, no association was observed between serum IGFBP-2 levels and auxological or metabolic parameters in children with normal BMIs. These results suggested that IGFBP-2 might be a promising marker for early recognition of insulin resistance, particularly in overweight or obese children, regardless of pubertal stage.

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Strict postprandial glycemic control may have a preventive effect on atherogenesis in patients with type 2 diabetes. The α-glucosidase inhibitor (α-GI) miglitol is useful for controlling the early postprandial increase of glucose, but the combined effect of miglitol and multiple daily insulin injections (MDI) on glucose excursion has not been evaluated. First, we retrospectively compared the daily glucose profile, evaluated by self-monitoring of blood glucose (SMBG) at nine times on the day before discharge from hospital, between type 2 diabetic patients receiving MDI (n=81) or MDI plus miglitol at 150 mg daily (n=24). Second, we prospectively examined the effect of adding miglitol to MDI on the daily glucose profile (SMBG) in 19 other type 2 diabetic patients. Although the daily insulin dosage and the glucose level before meals did not differ between the two groups, the 1-h postprandial glucose level after each meal, 2-h glucose level after lunch and dinner, mean and standard deviation of glucose, and amplitude of glucose excursion were significantly lower or smaller in the MDI plus miglitol group than in the MDI group. All of these glucose parameters were significantly improved by adding miglitol to MDI in the prospective cohort of 19 patients. In conclusion, adding miglitol to MDI reduces postprandial glucose levels and attenuates daily glucose fluctuation in type 2 diabetic patients. This trial was registered with UMIN (no. UMIN000005383).

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Glucose-dependent insulinotropic polypeptide (GIP) secretion in diabetic Europeans with type 1 (T1DM) and type 2 (T2DM) following test meal (TM) has been shown to be normal. In Japanese patients with T2DM, GIP secretion was also normal. We determined whether GIP secretin is influenced by various factors. Plasma glucose (PG), serum insulin (s-IRI), serum C-peptide (s-CPR), and plasma total GIP (p-total GIP) levels were measured at 0, 30, and 60 minutes after TM (560 kcal) in patients with T1DM (n = 15, group 1) and T2DM (n = 29, group 2) treated with various medications. HbA1c was also measured. At baseline, means of age, BMI, HbA1c, PG, s-CPR, SUIT (secretory unit in transplantation) and p-total GIP were significantly lower in group 1 than in group 2. Each mean of postprandial p-total GIP levels after TM in all patients was more dramatically increased than other factors. The area under the curve (AUC) of p-total GIP levels in early-phase (0 to 30 min) was significantly positively correlated with BMI in group 2 but not in group 1, and not with other factors. These results indicate that the GIP secretion after TM in diabetic Japanese patients was dramatically increased, and the AUC of GIP secretion in early-phase was positively correlated with BMI in non-obese and obese patients with T2DM, but not with T1DM. The increase was not influenced by gender, age, glycemic control, duration of disease, micro- or macro-vascular disturbances, or oral drugs.

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