The diagnosis of congenital HI should be considered in any large newborn with hypoglycemia.
The diagnosis is established by: fasting glucose of <50 mg/dL with concomitant insulin level of >2.0 μU/mL, plasma beta-hydroxybutyrate <2.0 mmol/L and free fatty acids <1.5 mmol/L, and confirmed by an inappropriate glycemic response to intravenous glucagon (>30 mg/dL rise in serum glucose level after glucagon 1 mg IV).
There are two forms of HI: diffuse disease, an autosomal recessive disease, and focal nodular disease, which is the result of inheritance of a paternal mutation and loss of heterozygosity for the maternal allele.
Children with congenital HI are best managed with a multidisciplinary approach that includes experienced clinicians from pediatric endocrinology, radiology, pathology, neonatology and surgery.
Patients with focal nodular disease are treated by complete resection of the tumor with negative margins.
Patients with diffuse disease are treated by near-total (95–98%) pancreatectomy.
The most accurate preoperative diagnostic test is [18F]fluoro-L-DOPA PET CT scan, which is currently available at very few centers.
Postoperative care after partial pancreatectomy almost always initially involves a continuous intravenous glucose infusion and sometimes a temporary insulin infusion.
Postoperative care after near-total pancreatectomy may require insulin (1/3), glycemic medications (1/3), or no medication (1/3).
Congenital hyperinsulinism is such a rare condition that few pediatric surgical centers can accumulate a large number of cases. Dr. Adzick outlines an approach that is state-of-the-art and clearly based on experience with a large number of patients over many years. There are several insightful conclusions to be drawn from this nice summary: (1) Case volume and experience are necessary to generate consistently good results and a very low complication rate. (2) PET-CT scanning with [18F]fluoro-L-DOPA is clearly the most accurate and clinically useful study for preoperative diagnosis and localization of focal lesions. Although currently limited in its availability, I expect that it will soon be the gold standard test for this condition. (3) Laparoscopic techniques are clearly feasible in the treatment of patients with HI and will likely become standard for initial biopsy and diagnosis and probably for the resection of focal lesions. (4) As we learn more about the genetics and molecular biology of congenital HI, we will soon have many more options for diagnosis, classification and treatment, perhaps in some cases obviating the need for surgical intervention. (5) Infants with hyperinsulinism should always be managed very aggressively with high-dose intravenous glucose infusion (via central venous catheter, if necessary), a trial of available glycemic medications and the frequent monitoring of blood glucose levels in an intensive care setting, as the long-term neurodevelopmental sequelae of hypoglycemia can be profound, devastating and irreversible.