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Tzy Harn Chua Department of Endocrinology, Changi General Hospital, Singapore

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Wann Jia Loh Department of Endocrinology, Changi General Hospital, Singapore

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Summary

Severe hyponatremia and osmotic demyelination syndrome (ODS) are opposite ends of a spectrum of emergency disorders related to sodium concentrations. Management of severe hyponatremia is challenging because of the difficulty in balancing the risk of overcorrection leading to ODS as well as under-correction causing cerebral oedema, particularly in a patient with chronic hypocortisolism and hypothyroidism. We report a case of a patient with Noonan syndrome and untreated anterior hypopituitarism who presented with symptomatic hyponatremia and developed transient ODS.

Learning points:

  • Patients with severe anterior hypopituitarism with severe hyponatremia are susceptible to the rapid rise of sodium level with a small amount of fluid and hydrocortisone.

  • These patients with chronic anterior hypopituitarism are at high risk of developing ODS and therefore, care should be taken to avoid a rise of more than 4–6 mmol/L per day.

  • Early recognition and rescue desmopressin and i.v. dextrose 5% fluids to reduce serum sodium concentration may be helpful in treating acute ODS.

Open access
Mawson Wang Department of Endocrinology and Diabetes, Blacktown Hospital, Sydney, Australia
Blacktown Clinical School, School of Medicine, Western Sydney University, Sydney, Australia

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Benjamin Jonker Department of Neurosurgery, St. Vincent’s Hospital, Sydney, Australia

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Louise Killen Department of Pathology, St. Vincent’s Hospital, Sydney, Australia

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Yvonne Bogum NSW Health Pathology East, Prince of Wales Hospital, Sydney, Australia

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Ann McCormack Department of Endocrinology, St. Vincent’s Hospital, Sydney, Australia
Garvan Institute of Medical Research, Sydney, Australia
St. Vincent’s Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, Australia

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Ramy H Bishay Department of Endocrinology and Diabetes, Blacktown Hospital, Sydney, Australia
Blacktown Clinical School, School of Medicine, Western Sydney University, Sydney, Australia

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Summary

Cushing’s disease is a rare disorder characterised by excessive cortisol production as a consequence of a corticotroph pituitary tumour. While the primary treatment is surgical resection, post-operative radiation therapy may be used in cases of ongoing inadequate hormonal control or residual or progressive structural disease. Despite improved outcomes, radiotherapy for pituitary tumours is associated with hypopituitarism, visual deficits and, rarely, secondary malignancies. We describe an unusual case of a 67-year-old female with presumed Cushing’s disease diagnosed at the age of 37, treated with transsphenoidal resection of a pituitary tumour with post-operative external beam radiotherapy (EBRT), ketoconazole for steroidogenesis inhibition, and finally bilateral adrenalectomy for refractory disease. She presented 30 years after her treatment with a witnessed generalised tonic-clonic seizure. Radiological investigations confirmed an extracranial mass infiltrating through the temporal bone and into brain parenchyma. Due to recurrent generalised seizures, the patient was intubated and commenced on dexamethasone and anti-epileptic therapy. Resection of the tumour revealed a high-grade osteoblastic osteosarcoma. Unfortunately, the patient deteriorated in intensive care and suffered a fatal cardiac arrest following a likely aspiration event. We describe the risk factors, prevalence and treatment of radiation-induced osteosarcoma, an exceedingly rare and late complication of pituitary irradiation. To our knowledge, this is the longest reported latency period between pituitary irradiation and the development of an osteosarcoma of the skull.

Learning points:

  • Cushing’s disease is treated with transsphenoidal resection as first-line therapy, with radiotherapy used in cases of incomplete resection, disease recurrence or persistent hypercortisolism.

  • The most common long-term adverse outcome of pituitary tumour irradiation is hypopituitarism occurring in 30–60% of patients at 10 years, and less commonly, vision loss and oculomotor nerve palsies, radiation-induced brain tumours and sarcomas.

  • Currently proposed characteristics of radiation-induced osteosarcomas include: the finding of a different histological type to the primary tumour, has developed within or adjacent to the path of the radiation beam, and a latency period of at least 3 years.

  • Treatment of osteosarcoma of the skull include complete surgical excision, followed by systemic chemotherapy and/or radiotherapy.

  • Overall prognosis in radiation-induced sarcoma of bone is poor.

  • Newer techniques such as stereotactic radiosurgery may reduce the incidence of radiation-induced malignancies.

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Yuri Tanaka Division of Neurology, Respirology, Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan

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Taisuke Uchida Division of Neurology, Respirology, Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan

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Hideki Yamaguchi Division of Neurology, Respirology, Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan

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Yohei Kudo Division of Neurology, Respirology, Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan

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Tadato Yonekawa Division of Neurology, Respirology, Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan

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Masamitsu Nakazato Division of Neurology, Respirology, Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan

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Summary

We report the case of a 48-year-old man with thyroid storm associated with fulminant hepatitis and elevated levels of soluble interleukin-2 receptor (sIL-2R). Fatigue, low-grade fever, shortness of breath, and weight loss developed over several months. The patient was admitted to the hospital because of tachycardia-induced heart failure and liver dysfunction. Graves’ disease with heart failure was diagnosed. He was treated with methimazole, inorganic iodide, and a β-blocker. On the day after admission, he became unconscious with a high fever and was transferred to the intensive care unit. Cardiogenic shock with atrial flutter was treated with intra-aortic balloon pumping and cardioversion. Hyperthyroidism decreased over 10 days, but hepatic failure developed. He was diagnosed with thyroid storm accompanied by fulminant hepatitis. Laboratory investigations revealed elevated levels of sIL-2R (9770 U/mL). The fulminant hepatitis was refractory to plasma exchange and plasma filtration with dialysis, and no donors for liver transplantation were available. He died of hemoperitoneum and gastrointestinal hemorrhage due to fulminant hepatitis 62 days after admission. Elevated circulating levels of sIL-2R might be a marker of poor prognosis in thyroid storm with fulminant hepatitis.

Learning points:

  • The prognosis of thyroid storm when fulminant hepatitis occurs is poor.

  • Liver transplantation is the preferred treatment for fulminant hepatitis induced by thyroid storm refractory to plasma exchange.

  • Elevated levels of soluble interleukin-2 receptor might be a marker of poor prognosis in patients with thyroid storm.

Open access
Mohammed Faraz Rafey Galway University Hospitals, Galway, Ireland
HRB Clinical Research Facility, National University of Ireland Galway, Galway, Ireland

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Arslan Butt Galway University Hospitals, Galway, Ireland

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Barry Coffey Galway University Hospitals, Galway, Ireland

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Lisa Reddington Galway University Hospitals, Galway, Ireland

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Aiden Devitt Galway University Hospitals, Galway, Ireland

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David Lappin Galway University Hospitals, Galway, Ireland

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Francis M Finucane Galway University Hospitals, Galway, Ireland
HRB Clinical Research Facility, National University of Ireland Galway, Galway, Ireland

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Summary

We describe two cases of SGLT2i-induced euglycaemic diabetic ketoacidosis, which took longer than we anticipated to treat despite initiation of our DKA protocol. Both patients had an unequivocal diagnosis of type 2 diabetes, had poor glycaemic control with a history of metformin intolerance and presented with relatively vague symptoms post-operatively. Neither patient had stopped their SGLT2i pre-operatively, but ought to have by current treatment guidelines.

Learning points:

  • SGLT2i-induced EDKA is a more protracted and prolonged metabolic derangement and takes approximately twice as long to treat as hyperglycaemic ketoacidosis.

  • Surgical patients ought to stop SGLT2i medications routinely pre-operatively and only resume them after they have made a full recovery from the operation.

  • While the mechanistic basis for EDKA remains unclear, our observation of marked ketonuria in both patients suggests that impaired ketone excretion may not be the predominant metabolic lesion in every case.

  • Measurement of insulin, C-Peptide, blood and urine ketones as well as glucagon and renal function at the time of initial presentation with EDKA may help to establish why this problem occurs in specific patients.

Open access
Sarah W Y Poon Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong

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Karen K Y Leung Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong

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Joanna Y L Tung Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong

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Summary

Severe hypertriglyceridemia is an endocrine emergency and is associated with acute pancreatitis and hyperviscosity syndrome. We describe an infant with lipoprotein lipase deficiency with severe hypertriglyceridemia who presented with acute pancreatitis. She was managed acutely with fasting and intravenous insulin infusion, followed by low-fat diet with no pharmacological agent. Subsequent follow-up until the age of 5 years showed satisfactory lipid profile and she has normal growth and development.

Learning points:

  • Hypertriglyceridemia-induced acute pancreatitis has significant morbidity and mortality, and prompt treatment is imperative.

  • When no secondary causes are readily identified, genetic evaluation should be pursued in hypertriglyceridemia in children.

  • Intravenous insulin is a safe and effective acute treatment for hypertriglyceridemia in children, even in infants.

  • Long-term management with dietary modifications alone could be effective for primary hypertriglyceridemia due to lipoprotein lipase deficiency, at least in early childhood phase.

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Daphne Yau Departments of Paediatric Endocrinology, Royal Manchester Children’s Hospital, Manchester, UK

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Maria Salomon-Estebanez Departments of Paediatric Endocrinology, Royal Manchester Children’s Hospital, Manchester, UK

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Amish Chinoy Departments of Paediatric Endocrinology, Royal Manchester Children’s Hospital, Manchester, UK

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John Grainger Departments of Paediatric Haematology, Royal Manchester Children’s Hospital, Manchester, UK

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Ross J Craigie Departments of Paediatric Surgery, Royal Manchester Children’s Hospital, Manchester, UK

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Raja Padidela Departments of Paediatric Endocrinology, Royal Manchester Children’s Hospital, Manchester, UK

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Mars Skae Departments of Paediatric Endocrinology, Royal Manchester Children’s Hospital, Manchester, UK

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Mark J Dunne Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK

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Philip G Murray Departments of Paediatric Endocrinology, Royal Manchester Children’s Hospital, Manchester, UK

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Indraneel Banerjee Departments of Paediatric Endocrinology, Royal Manchester Children’s Hospital, Manchester, UK

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Summary

Congenital hyperinsulinism (CHI) is an important cause of severe hypoglycaemia in infancy. To correct hypoglycaemia, high concentrations of dextrose are often required through a central venous catheter (CVC) with consequent risk of thrombosis. We describe a series of six cases of CHI due to varying aetiologies from our centre requiring CVC for the management of hypoglycaemia, who developed thrombosis in association with CVC. We subsequently analysed the incidence and risk factors for CVC-associated thrombosis, as well as the outcomes of enoxaparin prophylaxis. The six cases occurred over a 3-year period; we identified an additional 27 patients with CHI who required CVC insertion during this period (n = 33 total), and a separate cohort of patients with CHI and CVC who received enoxaparin prophylaxis (n = 7). The incidence of CVC-associated thrombosis was 18% (6/33) over the 3 years, a rate of 4.2 thromboses/1000 CVC days. There was no difference in the frequency of genetic mutations or focal CHI in those that developed thromboses. However, compound heterozygous/homozygous potassium ATP channel mutations correlated with thrombosis (R 2 = 0.40, P = 0.001). No difference was observed in CVC duration, high concentration dextrose or glucagon infused through the CVC. In patients receiving enoxaparin prophylaxis, none developed thrombosis or bleeding complications. The characteristics of these patients did not differ significantly from those with thrombosis not on prophylaxis. We therefore conclude that CVC-associated thrombosis can occur in a significant proportion (18%) of patients with CHI, particularly in severe CHI, for which anticoagulant prophylaxis may be indicated.

Learning points:

  • CVC insertion is one of the most significant risk factors for thrombosis in the paediatric population.

  • Risk factors for CVC-associated thrombosis include increased duration of CVC placement, malpositioning and infusion of blood products.

  • To our knowledge, this is the first study to evaluate CVC-associated thrombosis in patients with congenital hyperinsulinism (CHI).

  • The incidence of CVC-associated thrombosis development is significant (18%) in CHI patients and higher compared to other neonates with CVC. CHI severity may be a risk factor for thrombosis development.

  • Although effective prophylaxis for CVC-associated thrombosis in infancy is yet to be established, our preliminary experience suggests the safety and efficacy of enoxoaparin prophylaxis in this population and requires on-going evaluation.

Open access
Ved Bhushan Arya Department of Paediatric Endocrinology, Variety Club Children’s Hospital, King’s College Hospital NHS Foundation Trust, London, UK

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Jennifer Kalitsi Department of Paediatric Endocrinology, Variety Club Children’s Hospital, King’s College Hospital NHS Foundation Trust, London, UK

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Ann Hickey Department of Neonatology, King’s College Hospital NHS Foundation Trust, London, UK

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Sarah E Flanagan Institute of Biomedical and Clinical Science, University of Exeter, Exeter, UK

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Ritika R Kapoor Department of Paediatric Endocrinology, Variety Club Children’s Hospital, King’s College Hospital NHS Foundation Trust, London, UK

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Summary

Diazoxide is the first-line treatment for patients with hyperinsulinaemic hypoglycaemia (HH). Approximately 50% of patients with HH are diazoxide resistant. However, marked diazoxide sensitivity resulting in severe hyperglycaemia is extremely uncommon and not reported previously in the context of HH due to HNF4A mutation. We report a novel observation of exceptional diazoxide sensitivity in a patient with HH due to HNF4A mutation. A female infant presented with severe persistent neonatal hypoglycaemia and was diagnosed with HH. Standard doses of diazoxide (5 mg/kg/day) resulted in marked hyperglycaemia (maximum blood glucose 21.6 mmol/L) necessitating discontinuation of diazoxide. Lower dose of diazoxide (1.5 mg/kg/day) successfully controlled HH in the proband, which was subsequently confirmed to be due to a novel HNF4A mutation. At 3 years of age, the patient maintains age appropriate fasting tolerance on low dose diazoxide (1.8 mg/kg/day) and has normal development. Diagnosis in proband’s mother and maternal aunt, both of whom carried HNF4A mutation and had been diagnosed with presumed type 1 and type 2 diabetes mellitus, respectively, was revised to maturity-onset diabetes of young (MODY). Proband’s 5-year-old maternal cousin, also carrier of HNF4A mutation, had transient neonatal hypoglycaemia. To conclude, patients with HH due to HNF4A mutation may require lower diazoxide than other group of patients with HH. Educating the families about the risk of marked hyperglycaemia with diazoxide is essential. The clinical phenotype of HNF4A mutation can be extremely variable.

Learning points:

  • Awareness of risk of severe hyperglycaemia with diazoxide is important and patients/families should be accordingly educated.

  • Some patients with HH due to HNF4A mutations may require lower than standard doses of diazoxide.

  • The clinical phenotype of HNF4A mutation can be extremely variable.

Open access
Saurabh Uppal Departments of Paediatric Endocrinology, Alder Hey Children’s NHS Foundation Trust, Liverpool, UK

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James Blackburn Departments of Paediatric Endocrinology, Alder Hey Children’s NHS Foundation Trust, Liverpool, UK

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Mohammed Didi Departments of Paediatric Endocrinology, Alder Hey Children’s NHS Foundation Trust, Liverpool, UK

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Rajeev Shukla Departments of Pathology, Alder Hey Children’s NHS Foundation Trust, Liverpool, UK

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James Hayden Departments of Oncology, Alder Hey Children’s NHS Foundation Trust, Liverpool, UK

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Senthil Senniappan Departments of Paediatric Endocrinology, Alder Hey Children’s NHS Foundation Trust, Liverpool, UK
Institute of Child Health, University of Liverpool, Liverpool, UK

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Summary

Beckwith–Wiedemann syndrome (BWS) can be associated with embryonal tumours and congenital hyperinsulinism (CHI). We present an infant with BWS who developed congenital hepatoblastoma and Wilms’ tumour during infancy. The infant presented with recurrent hypoglycaemia requiring high intravenous glucose infusion and was biochemically confirmed to have CHI. He was resistant to diazoxide but responded well to octreotide and was switched to Lanreotide at 1 year of age. Genetic analysis for mutations of ABCC8 and KCNJ11 were negative. He had clinical features suggestive of BWS. Methylation-sensitive multiplex ligation-dependent probe amplification revealed hypomethylation at KCNQ1OT1:TSS-DMR and hypermethylation at H19 /IGF2:IG-DMR consistent with mosaic UPD(11p15). Hepatoblastoma was detected on day 4 of life, which was resistant to chemotherapy, requiring surgical resection. He developed Wilms’ tumour at 3 months of age, which also showed poor response to induction chemotherapy with vincristine and actinomycin D. Surgical resection of Wilms’ tumour was followed by post-operative chemotherapy intensified with cycles containing cyclophosphamide, doxorubicin, carboplatin and etoposide, in addition to receiving flank radiotherapy. We report, for the first time, an uncommon association of hepatoblastoma and Wilms’ tumour in BWS in early infancy. Early onset tumours may show resistance to chemotherapy. UPD(11p15) is likely associated with persistent CHI in BWS.

Learning points:

  • Long-acting somatostatin analogues are effective in managing persistent CHI in BWS.

  • UPD(11)pat genotype may be a pointer to persistent and severe CHI.

  • Hepatoblastoma and Wilms’ tumour may have an onset within early infancy and early tumour surveillance is essential.

  • Tumours associated with earlier onset may be resistant to recognised first-line chemotherapy.

Open access
Sarah Kiff Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children, London, UK
Department of Endocrinology, Royal Hospital for Sick Children, Edinburgh, UK

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Carolyn Babb Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children, London, UK

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Maria Guemes Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children, London, UK
Genetics and Genomic Medicine Programme, Great Institute of Child Health, University College London, London, UK

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Antonia Dastamani Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children, London, UK

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Clare Gilbert Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children, London, UK

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Sarah E Flanagan Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, UK

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Sian Ellard Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, UK

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John Barton Department of Paediatric Endocrinology, Bristol Royal Hospital for Children, Bristol, UK

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M Dattani Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children, London, UK
Genetics and Genomic Medicine Programme, Great Institute of Child Health, University College London, London, UK

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Pratik Shah Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children, London, UK
Genetics and Genomic Medicine Programme, Great Institute of Child Health, University College London, London, UK

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Summary

We report a case of partial diazoxide responsiveness in a child with severe congenital hyperinsulinaemic hypoglycaemia (CHI) due to a homozygous ABCC8 mutation. A term baby, with birth weight 3.8 kg, born to consanguineous parents presented on day 1 of life with hypoglycaemia. Hypoglycaemia screen confirmed CHI. Diazoxide was commenced on day 7 due to ongoing elevated glucose requirements (15 mg/kg/min), but despite escalation to a maximum dose (15 mg/kg/day), intravenous (i.v.) glucose requirement remained high (13 mg/kg/min). Genetic testing demonstrated a homozygous ABCC8 splicing mutation (c.2041-1G>C), consistent with a diffuse form of CHI. Diazoxide treatment was therefore stopped and subcutaneous (s.c.) octreotide infusion commenced. Despite this, s.c. glucagon and i.v. glucose were required to prevent hypoglycaemia. A trial of sirolimus and near-total pancreatectomy were considered, however due to the significant morbidity potentially associated with these, a further trial of diazoxide was commenced at 1.5 months of age. At a dose of 10 mg/kg/day of diazoxide and 40 µg/kg/day of octreotide, both i.v. glucose and s.c. glucagon were stopped as normoglycaemia was achieved. CHI due to homozygous ABCC8 mutation poses management difficulties if the somatostatin analogue octreotide is insufficient to prevent hypoglycaemia. Diazoxide unresponsiveness is often thought to be a hallmark of recessively inherited ABCC8 mutations. This patient was initially thought to be non-responsive, but this case highlights that a further trial of diazoxide is warranted, where other available treatments are associated with significant risk of morbidity.

Learning points:

  • Homozygous ABCC8 mutations are commonly thought to cause diazoxide non-responsive hyperinsulinaemic hypoglycaemia.

  • This case highlights that partial diazoxide responsiveness in homozygous ABCC8 mutations may be present.

  • Trial of diazoxide treatment in combination with octreotide is warranted prior to considering alternative treatments, such as sirolimus or near-total pancreatectomy, which are associated with more significant side effects.

Open access
A Veltroni ENETS Center of Excellence, Department of Medicine, University of Verona, Verona, Italy

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G Zambon ENETS Center of Excellence, Department of Medicine, University of Verona, Verona, Italy

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S Cingarlini ENETS Center of Excellence, Department of Oncology, University of Verona, Verona, Italy

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M V Davì ENETS Center of Excellence, Department of Medicine, University of Verona, Verona, Italy

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Summary

Insulin autoimmune syndrome (IAS), a rare cause of autoimmune hyperinsulinaemic hypoglycaemia, is relatively well known in Japan. The incidence in Caucasians is less than one-fifth of that reported in Japanese people, but it is becoming increasingly recognised worldwide in non-Asians as well. Drugs containing sulphydryl groups are known to be associated with the disease in genetically predisposed individuals. Moreover, several recent reports showed a direct association between the onset of IAS and the consumption of dietary supplements containing alpha-lipoic acid (LA). Insulinoma remains the most prevalent cause of hypersulinaemic hypoglycaemia in Caucasians. Consequently, primary investigation in these patients is generally focused on localisation of the pancreatic tumour, often with invasive procedures followed by surgery. We described a case of an Italian woman presenting to us with severe recurrent hypoglycaemia associated with high insulin and C-peptide levels and no evidence of pancreatic lesions at imaging diagnostic procedures. She had taken LA until 2 weeks before hospitalisation. After an evaluation of her drug history, an autoimmune form of hypoglycaemia was suspected and the titre of insulin autoantibodies was found to be markedly elevated. This allowed us to diagnose LA-related IAS, thus preventing any unnecessary surgery and avoiding invasive diagnostic interventions.

Learning points:

  • IAS is a rare cause of hyperinsulinaemic hypoglycaemia that typically affects Asian population, but it has been increasingly recognised in Caucasian patients.

  • It should be considered among the differential diagnosis of hyperinsulinaemic hypoglycaemia to avoid unnecessary diagnostic investigations and surgery.

  • It should be suspected in the presence of very high serum insulin levels (100–10  000  μU/mL) associated with high C-peptide levels.

  • There is a strong association with administration of drugs containing sulphydryl groups included LA, a dietary supplement commonly used in Western countries to treat peripheral neuropathy.

Open access