Introduction: Hyperinsulinaemic hypoglycemia (HH) represents the most common cause of hyperinsulinism in neonates, often termed as congenital hyperinsulinism of infancy (CHI). CHI is characterised by inappropriate raised insulin secretion from the pancreatic β-cells in relation to blood glucose concentration. Insulin suppresses NEFA and BOHB production. Neurological damage is a known risk associated with hyperinsulinaemic hypoglycaemia (HH).
Aim: To describe the clinical course and neurological outcome of three term neonates with severe hypoglycaemic brain injury who have had delayed diagnosis of hyperinsulinaemic hypoglycaemia.
Methodology: We recruited three patients who presented in the neonatal period with biochemically confirmed HH and referred to a tertiary endocrine hospital. Detailed clinical information was collected including MRI brain scan reports.
Clinical presentation: All three patients were born by normal vaginal delivery and were discharges within 2436 h of life.
|Case||Gestation (weeks)||Birth weight (g)||Presentation||Blood glucose (mmol/l) on presentation||Medications||MRI/CT brain|
|Case 1||36+4||2730||On day 3 with history of poor feeding and jerky movements.||0.4||Diazoxide and Chlorothiazide||MRI: grossly abnormal with evidence of cortical necrosis|
|Case 2||39||3250||On day 4 with lethargy, poor responsiveness and seizures.||0.6||Diazoxide and Chlorothiazide||MRI and CT subtle reduced attenuation within the cortex and white matter in keeping with generalised cerebral oedema related to hypoglycaemia|
|Case 3||38||3460||On day 3 with poor feeding, lethargy and seizures.||<0.3||Diazoxide and Chlorothiazide.||MRI bilateral extensive parietal occipital lobe infarction with diffuse cerebral swelling and oedema, typical of hypoglycaemic brain injury|
Conclusion: CHI leads to severe hypoglycaemia leading to severe brain injury and subsequent neurodevelopmental handicap. The identification, early diagnosis and prompt management of patients with hyperinsulinaemic hypoglycaemia are essential if brain damage is to be avoided. These infants are often difficult to identify due to the symptoms being non-specific.