Structural and functional differences in auto-antibody positive compared to auto-antibody negative hypothyroid patients with chronic thyroiditis.

Most primary hypothyroidism in adults is caused by chronic thyroiditis. Autoantibodies such as anti-thyroglobulin antibody (TgAb) and anti-thyroid peroxidase antibody (TPOAb) are involved in the pathogenesis of chronic thyroiditis. On the other hand, the clinical features of antibody-negative hypothyroidism are not clear. In this study, we aimed to determine the prevalence of thyroid-related autoantibodies in patients with primary hypothyroidism and to evaluate the differences in thyroid structure between antibody-positive and antibody-negative hypothyroidism. Among 804 patients who attended Kawasaki Medical School Hospital for thyroid hormone abnormalities or thyroid gland enlargement between January 1, 2010 and December 31, 2021, 237 patients with primary hypothyroidism who underwent thyroid antibody measurement and thyroid ultrasound examination were included. Participants were divided into groups according to antibody positivity/negativity, and differences in antibody positivity and thyroid structure were evaluated. In this study, 34.6% of patients had antibody-negative hypothyroidism. The positive rate of each antibody was 62.0% for TgAb and 49.4% for TPOAb. The participants with antibody-positive hypothyroidism had significantly larger thyroid gland on thyroid ultrasound examination (p < 0.05). Thyroid-stimulating hormone was significantly higher in participants with antibody-positive compared to antibody-negative hypothyroidism. The present study reveals a positive rate of thyroid-related autoantibodies in patients with hypothyroidism and the differences in thyroid structure between patients with and without antibodies. This study clearly show that the prevalence of antibody-negative chronic thyroiditis is quite high among hypothyroid patients, although this point needs confirmation by further investigations. The data in this study would be useful for the treatment of antibody-negative hypothyroid patients.

Correlation of Baba's diabetic neuropathy classification with various diabetes-related complications.

It is known that Baba's diabetic neuropathy classification (BDC) is useful in quantitative evaluation of Diabetic polyneuropathy (DPN). In this study, we aimed to investigate the possible association between BDC and various diabetic microvascular and macrovascular complications in patients whose neuropathy was evaluated with BDC. As the results, BDC was significantly correlated with the severity of diabetic retinopathy and nephropathy. BDC was also significantly correlated with history of myocardial infarction or cerebral infarction, carotid IMT, and ABI. These data suggest that BDC may be useful in predicting the presence of various diabetic microvascular and macrovascular complications. The data also support the idea that we should perform further investigation of other diabetes-related complications in patients with severe DPN.

Association between changes in pancreatic morphology and vascular complications in subjects with type 2 diabetes mellitus: a retrospective study.

Decreased pancreatic volume, increased pancreatic fat mass, and serrated pancreatic margins are characteristic morphological changes of the pancreas in subjects with type 2 diabetes mellitus. This retrospective study aimed to clarify the clinical significance of pancreatic morphological changes in subjects with type 2 diabetes mellitus who underwent abdominal magnetic resonance imaging. The mean age and HbA1c value were 59.1 ± 16.3 years old and 8.9 ± 2.3%, respectively. Pancreatic body mass corrected for body surface area (BSA) in subjects with diabetes mellitus was lower compared to those in normal glucose tolerance (49.4 ± 15.3 cm3 vs. 60.9 ± 7.8 cm3), although it did not reach a statistic significance. There was a negative correlation between BSA-corrected pancreatic volume and age, duration of diabetes, glycoalbumin, mean and max IMT, and there was a positive correlation between BSA-corrected pancreatic volume and HOMA2-ß. Serration of the pancreatic limbus was more often observed in subjects with diabetes mellitus compared to those in normal glucose tolerance (74.1% vs. 14.3%). Subjects with serrated changes were older and had higher HbA1c, and visceral fat area was significantly larger in subjects with serrated changes. BSA-corrected pancreatic volume in subjects with serrated changes was significantly smaller, and mean IMT was significantly thicker in subjects with serrulation. Furthermore, advanced diabetic retinopathy and diabetic nephropathy were more often observed in subjects with serrated changes. Taken together, decreased BSA-corrected pancreatic volume and serrated changes were associated with the progression of vascular complications in subjects with type 2 diabetes mellitus.

Usefulness of cortisol/ACTH ratio (CAR) for diagnosis of cushing's syndrome: comparison of CAR with findings in dexamethasone suppression test.

Cushing's syndrome and subclinical Cushing's syndrome (SCS) are conditions of increased cortisol secretion from the adrenal glands. Cushing's syndrome includes adrenocorticotropic hormone (ACTH)-dependent Cushing's syndrome (Cushing's disease) and ACTH-independent Cushing's syndrome (AICS). The purpose of this study was to investigate the diagnostic potential of the cortisol / adrenocorticotropic hormone (ACTH) ratio (CAR) for diagnosis of Cushing's syndrome or SCS in adult subjects. This was a single-center, retrospective, observational study. This study enrolled 44 subjects with SCS, 14 AICS, 10 CD, and 248 non-Cushing's syndrome subjects who had undergone a 1 mg dexamethasone suppression test (1 mg DST). Definition of SCS was as follows: no physical signs characteristic of Cushing syndrome and cortisol was ≥ 83 nmol/L in 1 mg DST. The diagnostic potential of CAR for diagnosis of Cushing's syndrome was evaluated by comparing the correlation between CAR and after-load cortisol level in 1 mg DST. As the results, there was a strong positive correlation between CAR and after-load cortisol level in subjects with AICS (r = 0.800, p < 0.005). CAR was 10,040 ± 4170 nmol/pmol in subjects with NCS, 17,535 ± 10,246 nmol/pmol in SCS, 101,221 ± 18,009 nmol/pmol in AICS, and 4324 ± 2051 nmol/pmol in CD, all of which were significantly higher compared to those with AICS (p < 0.0005). The cutoff values of CAR for screening at our institution were 11,849.6 nmol/pmol for AICS (AUC 0.935, p < 0.005, sensitivity 92.3%, specificity 83.5%) and 7006.1 nmol/pmol for CD (AUC 0.714, p < 0.05, sensitivity 100.0%, specificity 46.8%). There was a positive correlation between CAR and adrenal adenoma diameter in subjects with AICS (r = 0.508, p < 0.05), but there was no correlation between tumor diameter and CAR in subjects with SCS and CD. In conclusion, high CAR indicates increased cortisol secretion from the adrenal glands. Since CAR is a simple indicator that can be easily evaluated by general practitioners as well as endocrinologists, we think CAR would be useful for the early detection of Cushing's syndrome.

Effect of Hyperglycemia-Related Acute Metabolic Disturbance on Thyroid Function Parameters in Adults.

Non-thyroidal illness (NTI) is a condition in which the hypothalamic-pituitary-thyroid system and thyroid hormone metabolism are abnormal due to non-thyroidal diseases. Although NTI has been reported to occur in hyperglycemic emergencies in children, there have been few studies in adult cases. In this study, we examined adult patients with hyperglycemia regarding the frequency of NTI and its triggers. Adult diabetic patients who were hospitalized for diabetic ketosis (DK), diabetic ketoacidosis (DKA), or hyperglycemic hyperosmolarity syndrome (HHS) were included in the study. Compared with the DK group, the DKA and HHS groups had higher admission blood glucose, Anion Gap, serum osmolality, creatinine, and urea nitrogen, and lower pH and eGFR. The frequency of NTI in the DKA, HHS, and DK groups was 80%, 70%, and 50%, respectively, and thyroid stimulating hormone (TSH) and free thyroxine 3 (FT3) were significantly improved after treatment for hyperglycemia. Multiple regression analysis showed a significant correlation between the decrease in FT3 level and 3-hydroxybutyrate and albumin. Acute metabolic failure associated with hyperglycemia tends to be associated with a high rate of NTI and low FT3 levels at the start of treatment. The data in this study clearly shows that transient NTI is frequently observed in subjects with acute metabolic disorders such as DKA, HHS and DK. In addition, we should bear in mind that thyroid hormone replacement therapy is not necessary in subjects with NTI due to DKA, HHS and DK, especially when overt symptoms of hypothyroidism are not observed.

Central Diabetes Insipidus Due to IgG4-related Hypophysitis That Required over One Year to Reach the Final Diagnosis Due to Symptoms Being Masked by Sialadenitis.

Pituitary inflammation due to IgG4-related disease is a rare condition and is sometimes accompanied by central diabetes insipidus. Central diabetes insipidus produces a strong thirst sensation, which may be difficult to distinguish when complicated by salivary insufficiency. A 45-year-old man was admitted to our department for a thorough examination of his thirst and polyuria. He had suddenly developed these symptoms more than one year earlier and visited an oral surgeon. Swelling of the left submandibular gland, right parotid gland, and cervical lymph nodes had been observed. Since his IgG4 level was relatively high at 792 mg/dL and a lip biopsy showed high plasmacytoid infiltration around the gland ducts, he had been diagnosed with IgG4-related disease. He had started taking 0.4 mg/kg/day of prednisolone, and his chief complaint temporarily improved. However, since the symptom recurred, he was referred to our institution. After admission, to examine the cause of his thirst and polyuria, we performed a water restriction test, vasopressin loading test, hypertonic saline loading test and pituitary magnetic resonance imaging. Based on the findings, we diagnosed him with central diabetes insipidus due to IgG4-related hypophysitis. We increased the dose of prednisolone to 0.6 mg/kg/day and started 10 µg/day of intranasal desmopressin. His symptoms were subsequently alleviated, and his serum IgG4 level finally normalized. We should remember that IgG4-related disease can be accompanied by hypophysitis and that central diabetes insipidus is brought about by IgG4-related hypophysitis. This case report should remind physicians of the fact that pituitary inflammation due to IgG4-related disease is very rare and can be masked by symptoms due to salivary gland inflammation, which can lead to pitfalls in the diagnosis in clinical practice.

Glucagon Test Is a Useful Predictor of Withdrawal From Insulin Therapy in Subjects With Type 2 Diabetes Mellitus.

There are many tests for evaluating endogenous insulin secretory capacity. However, there are only a limited number of studies that have examined in detail in clinical practice which method most accurately reflects the ability to secrete endogenous insulin especially in hyperglycemic state. The purpose of this study was to find the endogenous insulin secretory capacity and a possible predictor of insulin withdrawal in subjects with type 2 diabetes requiring hospitalization due to hyperglycemia. In the endogenous insulin secretory test during hospitalization, CPR, CPR index, and ΔCPR after glucagon loading were all significantly higher in the insulin withdrawal group. On the other hand, there were no difference in fasting CPR index, HOMA-ß, SUIT, and 24-hour urinary CPR excretion between the two groups. In the glucagon test of the insulin withdrawal group, the cutoff value of ΔCPR was 1.0 ng/mL, the withdrawal rate of ΔCPR of 1.0 ng/mL or more was 69.2%, and the withdrawal rate of less than 1.0 ng/mL was 25.0%. In conclusion, it is likely that glucagon test is the most powerful tool for predicting the possibility of insulin withdrawal as well as for evaluating endogenous insulin secretory capacity in subjects with type 2 diabetes requiring hospitalization due to hyperglycemia.