How should we differentiate hypoglycaemia in non-diabetic patients?

Hypoglycaemic syndromes are rare in apparently healthy individuals and their diagnosis can be a difficult challenge for clinicians as there are no shared guidelines that suggest how to approach patients with a suspect hypoglycaemic disorder. Since hypoglycaemia symptoms are common and nonspecific, it's necessary to document the Whipple Triad (signs and/or symptoms compatible with hypoglycaemia; relief of symptoms following glucose administration; low plasma glucose levels) before starting any procedure. Once the triad is documented, a meticulous anamnesis and laboratory tests (blood glucose, insulin, proinsulin, C-peptide, β-hydroxybutyrate and anti-insulin antibodies) should be performed. Results can guide the physician towards further specific tests, concerning the suspected disease. In this review, we consider all current causes of hypoglycaemia, including rare diseases such as nesidioblastosis and Hirata's syndrome, describe appropriate tests for diagnosis and suggest strategies to differentiate hypoglycaemia aetiology.

[Reactive hypoglycaemia, a frequently mentioned functional disorder, yet overestimated in clinical practice]

Malaises are often attributed to hypoglycaemia in nondiabetic people who don't have any other serious medical problem. Reactive hypoglycaemia, the most frequent one, may be considered as a functional disorder. However, its diagnosis is often overused, because not really demonstrated in most instances. The diagnosis of hypoglycaemia should be structured, based upon the Whipple triad. First, the medical interrogatory must search for adrenergic and neuroglucopenic symptoms that suggest hypoglycaemia. Second, if the malaise is due to a hypoglycaemia, it should resume rapidly after the administration of sugar. Third, hypoglycaemia must be confirmed by a measurement of a low glucose level at the time of a malaise. The latter approach is facilitated by the use of home blood monitoring, a strategy that is now preferred to the use of an oral glucose tolerance test, a non-physiological test far from real-life conditions. When the diagnosis is made based upon this triad, the medical interview should precise the severity of the symptoms and focus on the chronology of the malaises, typically 2-3 hours after a sugar-enriched meal in case of a reactive hypoglycaemia. Therapeutic approach of this functional disorder mostly relies on dietary advices.

Hyperinsulinemic hypoglycemia in adolescents: case report and systematic review

Background

Hyperinsulinemic hypoglycemia is the most common cause of severe and persistent hypoglycemia in neonates and children. It is a heterogeneous condition with dysregulated insulin secretion, which persists in the presence of low blood glucose levels.

Case presentation

We report a case of a 15 year-old male with hyperinsulinemic hypoglycemia, who underwent a subtotal pancreatectomy after inadequate response to medical therapy. Pathological examination was positive for nesidioblastosis (diffuse β-cell hyperplasia by H-E and immunohistochemical techniques). The patient’s blood glucose levels normalized after surgery and he remains asymptomatic after 1 year of follow-up. The systematic review allowed us to identify 41 adolescents from a total of 205 cases reported in 22 manuscripts, from a total of 454 found in the original search done in PubMed and Lilacs.

Conclusions

Although very well reported in children, hyperinsulinemic hypoglycemia can occur in adolescents or young adults, as it happens in our reported case. These patients can be seen, treated and reported by pediatricians or adult teams either way due to the wide age range used to define adolescence. Most of them do not respond to medical treatment, and subtotal distal pancreatectomy has become the elected procedure with excellent long-term response in the vast majority.