Massive insulin overdoses and prolonged hypoglycaemia are uncommon and may represent suicide attempts. A 34-year-old male with Type-1 DM, anxiety, and depression uses a basal bolus insulin regimen. He self-injected 2700 units of Toujeo and 960 units of Novorapid at different abdominal and upper thigh sites. He regretted it and called 911 within 15 minutes. Before he was hospitalised, emergency services gave him 1 mg of glucagon and 15 grams of glucose.
Table-1 shows his hospitalisation progression.
Recurrent hypoglycaemia and elevated blood insulin levels have persisted for 93 hours following insulin administration (Figure-1).
Our patient developed severe acute liver impairment 48 hours after insulin administration. Blood tests at admission showed normal liver function (Table-2).
Liver screenings were negative. Upper abdomen ultrasonography showed hepatomegaly without parenchymal abnormalities, suggesting hepatic glycogenosis. In 24–48 hours, liver function improved significantly (Figure-2).
Discussion
Subcutaneous insulin injection creates a depot under the skin. Absorption variability increases and absorption decreases as depot size increases [1]. Case reports show that long-acting insulin analogues such as glargine can cause prolonged hypoglycaemia [2, 3, 4]. High-dose intravenous glucose therapy for insulin excess can cause glycogenosis with increased liver enzymes [5]. Liver biopsy confirms glycogenosis, and CT imaging often shows hyper-dense liver [6]. Glycogenosis occurs without any significant irreversible hepatocyte damage or fibrosis. Stopping insulin and glucose infusions quickly resolves glycogenosis [6]. However, shock or ischemia may also boost liver enzyme levels. Mauriac syndrome is a severe form of glycogenosis and produces hepatomegaly, slow growth, late puberty, and Cushingoid facies [5]. Surgery to remove the insulin depot, glucocorticoids to promote insulin resistance, and glucagon are other methods to minimise glucose loading and prevent hypoglycaemia following an insulin overdose [7]. Understanding the pathophysiology of elevated liver enzymes following glucose infusions with excess insulin can help treating doctors avoid unnecessary tests [7].