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Hughes AE, Houghton JAL, Bunce B, Chakera AJ, Spyer G, Shepherd MH, Flanagan SE, Hattersley AT. Bringing precision medicine to the management of pregnancy in women with glucokinase-MODY: a study of diagnostic accuracy and feasibility of non-invasive prenatal testing. Diabetologia 2023; 66:1997-2006. [PMID: 37653058 PMCID: PMC10542291 DOI: 10.1007/s00125-023-05982-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 06/08/2023] [Indexed: 09/02/2023]
Abstract
AIMS/HYPOTHESIS In pregnancies where the mother has glucokinase-MODY (GCK-MODY), fetal growth is determined by fetal genotype. When the fetus inherits a maternal pathogenic GCK variant, normal fetal growth is anticipated, and insulin treatment of maternal hyperglycaemia is not recommended. At present, fetal genotype is estimated from measurement of fetal abdominal circumference on ultrasound. Non-invasive prenatal testing of fetal GCK genotype (NIPT-GCK) using cell-free DNA in maternal blood has recently been developed. We aimed to compare the diagnostic accuracy of NIPT-GCK with that of ultrasound, and determine the feasibility of using NIPT-GCK to guide pregnancy management. METHODS We studied an international cohort of pregnant women with hyperglycaemia due to GCK-MODY. We compared the diagnostic accuracy of NIPT-GCK with that of measurement of fetal abdominal circumference at 28 weeks' gestation (n=38) using a directly genotyped offspring sample as the reference standard. In a feasibility study, we assessed the time to result given to clinicians in 43 consecutive pregnancies affected by GCK-MODY between July 2019 and September 2021. RESULTS In terms of diagnostic accuracy, NIPT-GCK was more sensitive and specific than ultrasound in predicting fetal genotype (sensitivity 100% and specificity 96% for NIPT-GCK vs sensitivity 53% and specificity 61% for fetal abdominal circumference 75th percentile). In terms of feasibility, a valid NIPT-GCK fetal genotype (≥95% probability) was reported in all 38 pregnancies with an amenable variant and repeated samples when needed. The median time to report was 5 weeks (IQR 3-8 weeks). For the 25 samples received before 20 weeks' gestation, results were reported at a median gestational age of 20 weeks (IQR 18-24), with 23/25 (92%) reported before 28 weeks. CONCLUSIONS/INTERPRETATION Non-invasive prenatal testing of fetal genotype in GCK-MODY pregnancies is highly accurate and is capable of providing a result before the last trimester for most patients. This means that non-invasive prenatal testing of fetal genotype is the optimal approach to management of GCK-MODY pregnancies.
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Affiliation(s)
- Alice E Hughes
- Faculty of Health and Life Sciences, University of Exeter Medical School, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Jayne A L Houghton
- Exeter Genomics Laboratory, Royal Devon University Healthcare NHS Foundation Trust, Exeter, UK
| | - Benjamin Bunce
- Exeter Genomics Laboratory, Royal Devon University Healthcare NHS Foundation Trust, Exeter, UK
| | - Ali J Chakera
- Faculty of Health and Life Sciences, University of Exeter Medical School, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
- Department of Diabetes and Endocrinology, Royal Sussex County Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton, UK
| | - Gill Spyer
- Faculty of Health and Life Sciences, University of Exeter Medical School, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
- Department of Diabetes and Endocrinology, Torbay Hospital, Torbay and South Devon NHS Foundation Trust, Torquay, UK
| | - Maggie H Shepherd
- Faculty of Health and Life Sciences, University of Exeter Medical School, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
- National Institute for Health and Care Research, Exeter Clinical Research Facility, Royal Devon University Healthcare NHS Foundation Trust, Exeter, UK
| | - Sarah E Flanagan
- Faculty of Health and Life Sciences, University of Exeter Medical School, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Andrew T Hattersley
- Faculty of Health and Life Sciences, University of Exeter Medical School, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK.
- National Institute for Health and Care Research, Exeter Clinical Research Facility, Royal Devon University Healthcare NHS Foundation Trust, Exeter, UK.
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Chakera AJ, Hurst PS, Spyer G, Ogunnowo-Bada EO, Marsh WJ, Riches CH, Yueh CY, Markkula SP, Dalley JW, Cox RD, Macdonald IA, Amiel SA, MacLeod KM, Heisler LK, Hattersley AT, Evans ML. Molecular reductions in glucokinase activity increase counter-regulatory responses to hypoglycemia in mice and humans with diabetes. Mol Metab 2018; 17:17-27. [PMID: 30146176 PMCID: PMC6197723 DOI: 10.1016/j.molmet.2018.08.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 08/02/2018] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE Appropriate glucose levels are essential for survival; thus, the detection and correction of low blood glucose is of paramount importance. Hypoglycemia prompts an integrated response involving reduction in insulin release and secretion of key counter-regulatory hormones glucagon and epinephrine that together promote endogenous glucose production to restore normoglycemia. However, specifically how this response is orchestrated remains to be fully clarified. The low affinity hexokinase glucokinase is found in glucose-sensing cells involved in glucose homeostasis including pancreatic β-cells and in certain brain areas. Here, we aimed to examine the role of glucokinase in triggering counter-regulatory hormonal responses to hypoglycemia, hypothesizing that reduced glucokinase activity would lead to increased and/or earlier triggering of responses. METHODS Hyperinsulinemic glucose clamps were performed to examine counter-regulatory responses to controlled hypoglycemic challenges created in humans with monogenic diabetes resulting from heterozygous glucokinase mutations (GCK-MODY). To examine the relative importance of glucokinase in different sensing areas, we then examined responses to clamped hypoglycemia in mice with molecularly defined disruption of whole body and/or brain glucokinase. RESULTS GCK-MODY patients displayed increased and earlier glucagon responses during hypoglycemia compared with a group of glycemia-matched patients with type 2 diabetes. Consistent with this, glucagon responses to hypoglycemia were also increased in I366F mice with mutated glucokinase and in streptozotocin-treated β-cell ablated diabetic I366F mice. Glucagon responses were normal in conditional brain glucokinase-knockout mice, suggesting that glucagon release during hypoglycemia is controlled by glucokinase-mediated glucose sensing outside the brain but not in β-cells. For epinephrine, we found increased responses in GCK-MODY patients, in β-cell ablated diabetic I366F mice and in conditional (nestin lineage) brain glucokinase-knockout mice, supporting a role for brain glucokinase in triggering epinephrine release. CONCLUSIONS Our data suggest that glucokinase in brain and other non β-cell peripheral hypoglycemia sensors is important in glucose homeostasis, allowing the body to detect and respond to a falling blood glucose.
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Affiliation(s)
- Ali J Chakera
- Institute of Clinical and Biomedical Sciences, University of Exeter, United Kingdom
| | - Paul S Hurst
- Wellcome Trust/ MRC Institute of Metabolic Science and Department of Medicine, University of Cambridge, United Kingdom
| | - Gill Spyer
- Institute of Clinical and Biomedical Sciences, University of Exeter, United Kingdom
| | - Emmanuel O Ogunnowo-Bada
- Wellcome Trust/ MRC Institute of Metabolic Science and Department of Medicine, University of Cambridge, United Kingdom
| | - William J Marsh
- Wellcome Trust/ MRC Institute of Metabolic Science and Department of Medicine, University of Cambridge, United Kingdom
| | - Christine H Riches
- Wellcome Trust/ MRC Institute of Metabolic Science and Department of Medicine, University of Cambridge, United Kingdom
| | - Chen-Yu Yueh
- Wellcome Trust/ MRC Institute of Metabolic Science and Department of Medicine, University of Cambridge, United Kingdom
| | - S Pauliina Markkula
- Wellcome Trust/ MRC Institute of Metabolic Science and Department of Medicine, University of Cambridge, United Kingdom
| | - Jeffrey W Dalley
- Behavioural and Clinical Neuroscience Institute and Departments of Psychology and Psychiatry, University of Cambridge, United Kingdom
| | - Roger D Cox
- MRC Harwell Institute, Mammalian Genetics Unit, Harwell Oxford, United Kingdom
| | - Ian A Macdonald
- MRC-ARUK Centre for Musculoskeletal Ageing and NIHR Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust/ University of Nottingham, Nottingham, United Kingdom
| | - Stephanie A Amiel
- Division of Diabetes and Nutritional Sciences, King's College London, United Kingdom
| | - Kenneth M MacLeod
- Institute of Clinical and Biomedical Sciences, University of Exeter, United Kingdom
| | - Lora K Heisler
- Rowett Institute, University of Aberdeen, United Kingdom
| | - Andrew T Hattersley
- Institute of Clinical and Biomedical Sciences, University of Exeter, United Kingdom.
| | - Mark L Evans
- Wellcome Trust/ MRC Institute of Metabolic Science and Department of Medicine, University of Cambridge, United Kingdom.
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Chakera AJ, Spyer G, Vincent N, Ellard S, Hattersley AT, Dunne FP. The 0.1% of the population with glucokinase monogenic diabetes can be recognized by clinical characteristics in pregnancy: the Atlantic Diabetes in Pregnancy cohort. Diabetes Care 2014; 37:1230-6. [PMID: 24550216 DOI: 10.2337/dc13-2248] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Identifying glucokinase monogenic diabetes (GCK-MODY) in pregnancy is important, as management is different from management for other forms of gestational diabetes mellitus (GDM) and there is no increased maternal risk of type 2 diabetes. We calculated the population prevalence of GCK-MODY in pregnancy and determined the clinical characteristics that differentiate pregnant women with GCK-MODY from those with GDM. RESEARCH DESIGN AND METHODS We calculated the population prevalence of GCK-MODY in pregnancy by testing a subset of patients from the population-based Atlantic Diabetes in Pregnancy (Atlantic DIP) study (n = 5,500). We sequenced for GCK mutations in 247 women with a fasting glucose ≥5.1 mmol/L and 109 randomly selected control subjects with normal fasting glucose. Using data from the cases found and 40 previously identified GCK-MODY pregnancies, we analyzed whether clinical criteria could be used to differentiate GCK-MODY from GDM. RESULTS Four women with fasting glucose ≥5.1 mmol/L were diagnosed with GCK-MODY. No cases were identified with normal fasting glucose. The population prevalence of GCK-MODY is 1.1 in 1,000 (95% CI 0.3-2.9 in 1,000) and prevalence in GDM is 0.9% (95% CI 0.3-2.3). Fasting glucose and BMI significantly differentiate GCK-MODY from GDM (P < 0.0001). Combined criteria of BMI <25 kg/m(2) and fasting glucose ≥5.5 mmol/L has a sensitivity 68%, specificity 96%, and number needed to test of 2.7 women with GDM to find one case of GCK-MODY. CONCLUSIONS Our large population cohort of pregnant women tested estimates the population prevalence of GCK-MODY of 1.1 in 1,000. We have shown routine clinical criteria that can identify which women should be tested for GCK-MODY in pregnancy.
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Abstract
AIM To assess determinants of fetal growth in the offspring of pregnant women with hyperglycaemia due to a heterozygous glucokinase (GCK) gene mutation. METHODS Details of gestational age at delivery, fetal birth weight and maternal antenatal treatment were collected from patients and retrospective case note review of 82 offspring born to 42 women with GCK gene mutations and 31 offspring born to 13 unaffected normoglycaemic women with an affected partner. Fetal genotype was determined using direct sequencing from either a mouth swab or a blood sample. RESULTS In mothers with GCK mutations, non-mutation-carrying offspring were heavier than mutation-carrying offspring (corrected birth weight 3.9 +/- 0.6 vs. 3.2 +/- 0.8 kg; P < 0.001) and more likely to be macrosomic (> 4.0 kg; 39% vs. 7%, P = 0.001). There was no difference in corrected birth weight between offspring of insulin- and diet-treated women (3.7 +/- 0.7 vs. 3.8 +/- 0.6 kg; P = 0.1), although insulin-treated mothers delivered earlier (37.5 +/- 1.7 vs. 38.9 +/- 2.3 weeks; P < 0.001) due to increased obstetric intervention. CONCLUSIONS Offspring of women with GCK mutations are at increased risk of macrosomia and its obstetric consequences. Fetal birth weight is predominantly altered by fetal genotype and not treatment of maternal hyperglycaemia with insulin. This probably reflects the large effect of a fetal GCK mutation on fetal insulin secretion and the difficulty in reducing the regulated maternal glycaemia caused by a glucose sensing defect in people with GCK mutations.
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Affiliation(s)
- G Spyer
- Institute of Biomedical Sciences, Peninsula Medical School, Exeter, UK.
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Shields BM, Spyer G, Slingerland AS, Knight BA, Ellard S, Clark PM, Hauguel-de Mouzon S, Hattersley AT. Mutations in the glucokinase gene of the fetus result in reduced placental weight. Diabetes Care 2008; 31:753-7. [PMID: 18184897 DOI: 10.2337/dc07-1750] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE In human pregnancy, placental weight is strongly associated with birth weight. It is uncertain whether there is regulation of the placenta by the fetus or vice versa. We aimed to test the hypothesis that placental growth is mediated, either directly or indirectly, by fetal insulin. RESEARCH DESIGN AND METHODS Birth weight and placental weight were measured in 43 offspring of 21 parents with mutations in the glucokinase (GCK) gene (25 had inherited the mutation and 18 had not), which results in reduced fetal insulin secretion. Birth weight, placental weight, umbilical cord insulin, and maternal glucose and insulin concentrations were measured in 573 nondiabetic, healthy, term pregnancies. RESULTS GCK mutation carriers were lighter and also had smaller placentas (610 vs. 720 g, P = 0.042). This difference was also seen in 17 discordant sibling pairs (600 vs. 720 g, P = 0.003). GCK mRNA was not detected in the placenta by RT-PCR. In the normal pregnancies, placental weight was strongly correlated with birth weight (r = 0.61, P < 0.001). Cord insulin concentrations were directly related to placental weight (r = 0.28) and birth weight (r = 0.36) (P < 0.001 for both). CONCLUSIONS These results suggest that insulin, directly or indirectly, plays a role in placental growth, especially as a mutation in the GCK gene, which is known to only alter fetal insulin secretion, results in altered placental weight. This finding is consistent with the preferential localization of the insulin receptors in the fetal endothelium of the placenta in the last trimester of pregnancy.
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Affiliation(s)
- Beverley M Shields
- Diabetes Research, Peninsula Medical School, Barrack Road, Exeter, EX2 5DW, UK
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Spyer G, Ellard S, Turnpenny PD, Hattersley AT, Vaidya B. Phenotypic multiple endocrine neoplasia type 2B, without endocrinopathy or RET gene mutation: implications for management. Thyroid 2006; 16:605-8. [PMID: 16839263 DOI: 10.1089/thy.2006.16.605] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The multiple endocrine neoplasia (MEN) type 2B is an autosomal dominant condition characterized by aggressive medullary C-cell tumors, pheochromocytoma, and a discrete physical appearance (marfanoid habitus, prominent corneal nerve fibers, thick lips, and mucosal and intestinal neuromas). A specific point mutation in the RET proto-oncogene is present in 95% cases. Occasionally cases present with the characteristic physical appearance of MEN 2B but no identifiable germline mutation or endocrinopathy, and it has been suggested that these patients may represent a discrete subgroup termed pure mucosal neuroma syndrome (MNS). We present a patient with MNS, who had a thyroidectomy at age 14.5 years with normal thyroid histology. Direct sequencing of all 20 exons of the RET gene showed no mutation. This case supports the suggestion that pure MNS can exist in the absence of an identifiable RET gene mutation. We suggest that prophylactic thyroidectomy is unnecessary in these patients although they should still be screened for endocrinopathy on a regular basis.
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Affiliation(s)
- Gill Spyer
- Department of Endocrinology, Royal Devon & Exeter Hospital NHS Foundation Trust, Exeter, United Kingdom
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Gooding KM, MacLeod KM, Spyer G, Ewings P, Tooke JE, Shore AC. Impact of hormone replacement therapy on microvascular function in healthy and Type 2 diabetic postmenopausal women. Diabet Med 2005; 22:536-42. [PMID: 15842506 DOI: 10.1111/j.1464-5491.2005.01456.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS Hormone replacement therapy (HRT) has been previously reported to modulate vascular function and cardiovascular risk. Its impact on the macrocirculation has previously been explored, however, little data is available on its impact on the microcirculation. This study aimed to determine the impact of HRT on microvascular function in healthy and Type 2 diabetic postmenopausal women (n=20 and 17, respectively). METHODS Microvascular function was assessed by skin maximum hyperaemia, skin hyperaemic response to iontophoretically applied acetylcholine (endothelial-dependent vasodilator) and sodium nitroprusside (endothelial-independent vasodilator), capillary pressure and the microvascular filtration capacity. Microvascular assessments were carried out at baseline and repeated following 6 months' oral hormone replacement therapy (1 mg oestradiol/0.5 mg norethisterone or 1 mg unopposed oestradiol for hysterectomized women). RESULTS Following 6 months' therapy there were no significant changes in microvascular assessments in the healthy women. In the diabetic women there was a reduction in the skin hyperaemic response to acetylcholine [median pretreatment peak response: 1.95 (25th, 75th centiles: 1.54, 2.30) V vs. post-treatment peak response: 1.53 (1.30, 1.91) V (P=0.011, Wilcoxon's signed rank test)] and sodium nitroprusside [median peak response 1.59 (1.37, 1.99) vs. 1.35 (0.92, 1.63) V (P=0.011)] with HRT, but no other changes. CONCLUSION These data suggests that HRT does not affect microvascular function in healthy women, but adversely affects it in diabetic women. These findings may help to explain why HRT fails to provide the predicted cardiovascular protection, and raises the possibility that HRT influences microangiopathy progression in diabetic women.
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Affiliation(s)
- K M Gooding
- Institute of Biomedical and Clinical Science, Peninsula Medical School, Exeter, UK.
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Sagen JV, Pearson ER, Johansen A, Spyer G, Søvik O, Pedersen O, Njølstad PR, Hattersley AT, Hansen T. Preserved insulin response to tolbutamide in hepatocyte nuclear factor-1alpha mutation carriers. Diabet Med 2005; 22:406-9. [PMID: 15787664 DOI: 10.1111/j.1464-5491.2005.01439.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS Diabetic subjects with mutations in the gene encoding hepatocyte nuclear factor (HNF)-1alpha (MODY3) are prone to develop hypoglycaemia at low doses of glibenclamide, interpreted as sulphonylurea hypersensitivity. The present study was undertaken to compare the plasma insulin responses to glucose and tolbutamide in HNF-1alpha mutation carriers with those of healthy control subjects. METHODS Seven mutation carriers; three normoglycaemic, two with impaired glucose tolerance, and two with newly detected diabetes, underwent an oral glucose tolerance test and a tolbutamide-modified intravenous glucose tolerance test with measurements of plasma insulin. Twenty-two healthy subjects served as controls. RESULTS The plasma insulin response to intravenous glucose was reduced in the HNF-1alpha mutation carriers compared to the control subjects, with an area under the curve (median (interquartile range)) of 812 min pmol/l (421, 1647) and 1933 min pmol/l (1521, 2908), respectively (P = 0.03). In striking contrast, the plasma insulin response to tolbutamide was preserved, with an area under the curve of 2109 min pmol/l (1126, 3172) and 2250 min pmol/l (1614, 3276) in the mutation carriers and control subjects, respectively. CONCLUSIONS HNF-1alpha mutation carriers are characterized by preserved tolbutamide-induced insulin secretion. Compared to healthy subjects, our MODY3 individuals did not show any increased serum insulin response to tolbutamide, suggesting that HNF-1alpha mutation carriers are not characterized by sulphonylurea hypersensitivity.
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Affiliation(s)
- J V Sagen
- Section of Paediatrics, Institute of Clinical Medicine, University of Bergen, Bergen, Norway.
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Vaidya B, Campbell V, Tripp JH, Spyer G, Hattersley AT, Ellard S. Premature birth and low birth weight associated with nonautoimmune hyperthyroidism due to an activating thyrotropin receptor gene mutation. Clin Endocrinol (Oxf) 2004; 60:711-8. [PMID: 15163335 DOI: 10.1111/j.1365-2265.2004.02040.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Nonautoimmune hyperthyroidism (NAH), a rare autosomal dominantly inherited condition characterized by nonremitting thyrotoxicosis and the absence of features of autoimmune thyrotoxicosis, can result from activating germline mutations in the thyrotropin receptor (TSHR) gene. We report clinical and genetic features of a new family with NAH, and highlight that premature delivery and low birth weight are important characteristics of this condition. PATIENTS AND METHODS Thyrotoxicosis was diagnosed in two children at the ages 20 months and 4 years and in their father at the age of 9 years. Both children were born prematurely by Caesarian section at 33 and 30 weeks following early rupture of the membranes. Their birth weights were 1750 g (27th centile) and 790 g (< 3rd centile), respectively. Mutation analysis of the TSHR gene was performed in both children and their parents by direct DNA sequencing. RESULTS A heterozygous germline mutation of the TSHR gene resulting in the substitution of serine (AGC) by asparagine (AAC) at codon 505 (S505N) was found, which co-segregated with thyrotoxicosis in the family. A review of all previously reported cases of NAH due to an activating TSHR germline mutation showed that the mean duration of gestation in these patients was significantly lower than in patients with inactivating TSHR mutations causing congenital hypothyroidism (35.8 weeks vs. 39.4 weeks, P = 0.003). In addition, the mean birth weight in patients with activating TSHR mutations was lower than in patients with inactivating TSHR mutations (2338 g vs. 3470 g, P = 0.004). CONCLUSIONS Premature delivery and low birth weight are consistent features of NAH due to activating TSHR germline mutations. This suggests a possible role for the fetal thyroid axis in the regulation of the timing of delivery and possibly fetal growth.
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Affiliation(s)
- Bijay Vaidya
- Institute of Biomedical and Clinical Science, Peninsula Medical School, Exeter, UK.
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Abstract
We report 2 insulin-treated pregnancies in a mother with hyperglycemia resulting from a glucokinase gene mutation. The inheritance of a glucokinase mutation in 1 child reduced his intrauterine growth (birth weight less than first percentile) by reducing fetal insulin secretion. We discuss the implications for obstetric management of patients with glucokinase mutations.
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Affiliation(s)
- G Spyer
- Department of Diabetes and Vascular Medicine, School of Postgraduate Medicine, Royal Devon and Exeter Hospital, Barrack Road, Exeter, UK
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Spyer G, Hattersley AT, MacDonald IA, Amiel S, MacLeod KM. Hypoglycaemic counter-regulation at normal blood glucose concentrations in patients with well controlled type-2 diabetes. Lancet 2000; 356:1970-4. [PMID: 11130525 DOI: 10.1016/s0140-6736(00)03322-5] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND Intensive treatment to achieve good glycaemic control in diabetic patients is limited by a high frequency of hypoglycaemia. The glucose concentrations at which symptoms and release of counter-regulatory hormones takes place have not been studied in patients with well controlled type-2 diabetes. METHODS We studied seven well controlled, non-insulin treated, type-2 diabetic patients (mean HbA1c [corrected according to Diabetes Control and Complications Trial] 7.4%, SD 1.0) and seven healthy controls matched for age, sex, and body mass index with a stepped hyperinsulinaemic hypoglycaemic glucose clamp. Symptoms, cognitive function, and counter-regulatory hormone concentrations were measured at each glucose plateau, and the glucose value at which there was a significant change from baseline was calculated. FINDINGS Symptom response took place at higher whole-blood glucose concentrations in diabetic patients than in controls. Counter-regulatory release of epinephrine, norepinephrine, growth hormone, and cortisol showed a similar pattern--eg, at blood glucose concentrations of 3.8 mmol/L [SD 0.4] vs 2.6 [0.3] for epinephrine. INTERPRETATION Glucose thresholds for counter-regulatory hormone secretion are altered in well controlled type-2 diabetic patients, so that both symptoms and counter-regulatory hormone release can take place at normal glucose values. This effect might protect type-2 diabetic patients against episodes of profound hypoglycaemia and make the achievement of normoglycaemia more challenging in clinical practice.
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Affiliation(s)
- G Spyer
- Department of Vascular Medicine and Diabetes Research, School of Postgraduate Medicine and Health Sciences, Exeter, Devon, UK
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Abstract
OBJECTIVE To assess complications of diagnostic cardiac catheterisation in a non-surgical centre by review of the first three years' experience and audit of 2804 diagnostic left heart procedures. DESIGN Analysis of a prospective database of cardiac catheter procedures. SETTING District general hospital without available on site cardiac surgery. RESULTS The rate of major complications of cardiac catheterisation was 0.07%. Mortality was 0. 07%, and the rate of arterial complications (requiring surgical repair) was 0.24% for brachial arteries and 0.17% for femoral. These results are comparable to those reported from national and international surgical centres. CONCLUSION A diagnostic cardiac catheterisation service can be offered in non-surgical hospitals without an increased risk to patients. It highlights the relevance of training in angioplasty and questions the appropriateness of starting preliminary invasive cardiology training of specialist registrars in district general hospitals.
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Affiliation(s)
- L D Smith
- Department of Cardiology, Royal Devon and Exeter Hospital, Barrack Road, Exeter EX2 5DW, UK
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