Valproic Acid-Induced Pancreatitis in a Pediatric Patient With 17q12 Duplication Syndrome

Drug-induced acute pancreatitis is an uncommon cause of acute pancreatitis. Among the common culprits is valproic acid (VPA) and its derivatives, i.e., Depakote. These medications are commonly prescribed for epilepsy, bipolar disorder, and migraines. Although VPA-induced pancreatitis is rare, it has a variable disease course and may progress to severe disease, which can become fatal. Our case reports a 14-year-old male with a history of 17q.12 duplication, focal epilepsy, autism spectrum disorder (ASD), and attention-deficit hyperactivity disorder (ADHD), who presented to the emergency department with acute abdominal pain, nausea, and decreased oral intake. Labs revealed elevated lipase (1,572 U/L) and amylase (137 U/L), and triglycerides and calcium levels were within the reference range. An abdominal ultrasound was negative. The patient was being treated for focal epilepsy with VPA, which had been increased from 500 mg twice daily to 500 mg in the morning and 625 mg in the evening one month prior. Other causes of pancreatitis were ruled out. Discontinuation of the VPA led to rapid clinical improvement and normalization of lab values. The Naranjo Adverse Drug Reaction Probability Scale indicated that this event was a "probable" adverse drug reaction. This adverse effect occurred with VPA monotherapy at therapeutic dosing in the absence of risk factors, in the setting of 17q12 duplication syndrome, ADHD, and ASD. The clear sequence of events between the increase in dosage, onset of symptoms, medication discontinuation, and resolution of symptoms strengthens the causal link between the drug and the reaction. VPA-induced pancreatitis, despite its low incidence, carries a high risk of severe disease and mortality. It is critical that clinicians monitor for this complication in patients taking VPA and its derivatives. This case expands the spectrum of patients who may be vulnerable to this adverse reaction and highlights the importance of swift identification and discontinuation of the drug.