Aims/hypothesis: The prevalence and mechanisms of diabetes in hereditary haemochromatosis are not known. We therefore measured glucose tolerance, insulin secretory capacity and insulin sensitivity in adults with haemochromatosis.Subjects and methods: Subjects recruited from referrals to a haemochromatosis clinic underwent OGTT and frequently sampled IVGTT. A chart review of former clinic patients was also performed. Results: The prevalence of diabetes (23%) and IGT (30%) was increased in haemochromatosis compared with matched control subjects (0% diabetes and 14% IGT). Subjects with haemochromatosis and diabetes were overweight (14%) or obese (86%). The prevalence of diabetes, as determined by chart review of fasting glucose values, in subjects who had haemochromatosis and were in the 40-79 years age range was 26%. Overall, patients with haemochromatosis and control subjects had similar values for acute insulin response to glucose and insulin sensitivity. However, patients with haemochromatosis and IGT had a 68% decrease in acute insulin response to glucose (p<0.02) compared with those with NGT. They were not insulin-resistant, exhibiting instead a 62% increase in insulin sensitivity (NS). Haemochromatosis subjects with diabetes exhibited further declines in acute insulin response to glucose, insulin resistance, or both.Conclusions/interpretation: Diabetes and IGT are common in haemochromatosis, justifying screening for diabetes and therapeutic phlebotomy. The major abnormality associated with IGT is decreased insulin secretory capacity. Diabetes is usually associated with obesity and concomitant insulin resistance.
Aims/hypothesis We recently demonstrated that humans with hereditary haemochromatosis have decreased insulin secretory capacity with a compensatory increase in insulin sensitivity. We therefore determined how these measures change after correction of tissue iron overload. Subjects and methods Five non-diabetic subjects who had been studied previously at the time of initial diagnosis by means of the OGTT and frequently sampled intravenous glucose tolerance tests (FSIVGTT) underwent phlebotomy to normalise their serum ferritin. After normalisation of ferritin they were studied again (33±4 months after the initial studies) by OGTT and FSIVGTT. Results Normalisation of tissue iron stores resulted in an average 1.8-fold increase in the integrated area under the insulin curve during OGTT (p<0.0001), but no significant change in the area under the glucose curve (10% decrease, p=0.32). After phlebotomy, there was a 2.2-fold increase in insulin secretory capacity as determined by FSIVGTT (acute insulin response to glucose [AIRg], p<0.02) but a concomitant 70% fall in insulin sensitivity (Si, p<0.05).The disposition index (AIRg×Si) was unchanged (5% increase, p=0.90). BMI and fasting glucose were unchanged. At the time of diagnosis of haemochromatosis, four of the subjects had IGT. After normalisation of ferritin, two achieved NGT and two remained with IGT, despite 2.5-and 3.7-fold increases in insulin secretory capacity. Conclusions/interpretation Insulin secretory capacity improves after normalisation of iron stores in subjects with hereditary haemochromatosis. Glucose tolerance status improves incompletely because of decreased insulin sensitivity after phlebotomy. We conclude that tissue iron levels are an important determinant of insulin secretion and insulin action.
Letters to the Editor Cerebellar ataxia in coeliac disease-no evidence of a humoral aetiology Sir, Many patients with dermatitis herpetiformis also have a small bowel enteropathy which responds to withdrawal of gluten from the diet. However, in this setting, coeliac disease is usually mild and rarely results in clinical malabsorption. Both disorders have a high association with HLA, B8 and DR3 antigens and are suspected to have, at least in part, an immune pathogenesis. Some 1000 of patients
A decrease in blood androgen levels is well documented in women who experience natural or surgical menopause. This change may be associated with various negative effects on bone metabolism in addition to psychosocial and sexuality aspects of life. A review of published information on androgen replacement therapy shows that major benefits may be achieved; unfortunately, only minimal quality information is available to help clinicians make decisions about this type of therapy. In this review, we point out the potential benefits and risks to bone, lipid and carbohydrate metabolism, and sexuality; in addition, we discuss potential risks of neoplasms and virilizing somatic changes. Long-term, physiologic, and well-designed androgen replacement studies should be performed to obtain the knowledge needed to guide therapy in this important area.
Context
Comprehensive genomic analysis of thyroid nodules for multiple classes of molecular alterations detected in a large series of fine-needle aspiration (FNA) samples has not been reported.
Objective
To determine the prevalence of clinically relevant molecular alterations in Bethesda categories III-VI (BCIII-VI) thyroid nodules.
Design
Retrospective analysis of FNA samples tested by ThyroSeq v3 using Genomic Classifier and Cancer Risk Classifier.
Setting
UPMC MGP laboratory.
Participants
A total of 50,734 BCIII-VI nodules from 48,225 patients.
Intervention
None
Main Outcome Measures
Prevalence of diagnostic, prognostic, and targetable genetic alterations.
Results
Among 50,734 informative FNA samples, 65.3% were test-negative, 33.9% positive, 0.2% positive for medullary carcinoma, and 0.6% positive for parathyroid. The benign call rate in BCIII-IV nodules was 68%. Among test-positive samples, 73.3% had mutations, 11.3% gene fusions, and 10.8% isolated copy number alteration. Comparing BCIII-IV nodules with BCV-VI nodules revealed a shift from predominantly RAS-like alterations to BRAF V600E-like alterations and fusions involving receptor tyrosine kinases (RTK). Using ThyroSeq Cancer Risk Classifier, a high-risk profile, which typically included TERT or TP53 mutations, was found in 6% of samples, more frequently BCV-VI. RNA-Seq confirmed ThyroSeq detection of novel RTK fusions in 98.2% of cases.
Conclusions
In this series, 68% of BCIII-IV nodules were classified as negative by ThyroSeq, potentially preventing diagnostic surgery in this subset of patients. Specific genetic alterations were detected in most BCV-VI nodules, with a higher prevalence of BRAF and TERT mutations
and targetable gene fusions compared to BCIII-IV nodules, offering prognostic and therapeutic information for patient management.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.