Plasmapheresis for Hypertriglyceridemia-Induced Acute Pancreatitis in a Child: A Case Report and Brief Review of the Literature
We present a case of hypertriglyceridemia-induced acute pancreatitis (HTG-AP) treated with plasmapheresis, which, to our knowledge, has not previously been reported in a child without diabetic ketoacidosis (DKA).
The patient is a 4-year-old nonobese boy with a recent history of mild acute pancreatitis (AP) notable for serum triglycerides 798 mg/dL 2 weeks before, who presented to an outside hospital with abdominal pain, vomiting, and intolerance of oral intake. Abdominal pain from the previous episode had never fully resolved. Laboratory results were significant for lipase 20,181 U/L, amylase 3093 U/L, and serum bicarbonate 14 mmol/L. Computed tomography showed diffusely edematous pancreas with ascites.
Upon arrival to our institution, he was ill appearing with severe abdominal pain, tachycardic, and hypotensive. His serum was grossly hemolyzed and lipemic. Triglycerides were greater than 2000 mg/dL and lipase was 2434 U/L. Serum glucose was 90 mg/dL, ionized calcium was low at 0.92 mmol/L, and creatinine was elevated at 1.4 mg/dL. Despite a total of 60-mL/kg normal saline boluses and intravenous fluids at 150% of maintenance, the patient's urine output remained less than 0.5 mL/kg per hour. Because his clinical picture was consistent with severe AP with associated systemic inflammatory response, the decision was made to lower serum triglycerides quickly through plasmapheresis to prevent further end-organ dysfunction.
He underwent 1 cycle of plasmapheresis on hospital day 2, which decreased his serum triglycerides to 343 mg/dL. Serum lipase postpheresis was 1148 U/L. He was nil per os and received total parenteral nutrition without lipids. In the days after his plasmapheresis, serum triglyceride level remained stable between 250 and 300 mg/dL. By hospital day 4, his abdominal pain and ascites had markedly improved and he began a fat-restricted diet of 5 g/d, with subsequent transition to 10 g/d. On hospital day 10, serum triglycerides rebounded to 835 mg/dL. However, given his stable clinical appearance, he was managed conservatively with fat restriction to 5 g/d and initiation of lipid-lowering pharmacologic therapy. Given the efficacy and safety of omega-3 fatty acids, he was started on 500-mg fish oil daily. Serum triglycerides downtrended to 720 mg/dL at time of discharge (Fig. 1). Since discharge, he has been on daily Lovaza (1000-mg omega-3 fatty acid) and a mildly fat-restricted diet (<30 g/d). His triglyceride levels have fluctuated from 70 to 485 mg/dL with intermittent symptoms of abdominal pain, but he has not had documented pancreatitis, required regular pain medications, or needed hospitalization.
Hypertriglyceridemia (HTG) is estimated to account for up to 6% of AP cases.1 The exact mechanism of pancreatitis is unknown; however, the most commonly accepted theory suggests that triglycerides are hydrolyzed by pancreatic lipase and that high levels of free fatty acids impair circulatory flow in pancreatic vascular beds, causing ischemia and triggering an inflammatory response.2 Severe HTG, defined as a serum triglyceride level greater than 1000 mg/dL, is an absolute risk factor for AP. Patients with HTG-AP are more likely to develop persistent systemic inflammatory response syndrome and organ failure.3
Causes of HTG in children may be categorized as primary or secondary. Primary HTG includes genetic defects in triglyceride synthesis or metabolism. Secondary HTG in the pediatric age group is caused by uncontrolled diabetes, metabolic syndrome, and medications.4 The triad of DKA, AP, and HTG is a rare clinical entity in children, described in case reports.5,6
Currently, there is no standard treatment for HTG-AP in children. Heparin and insulin infusions have been used successfully.7 Heparin releases lipoprotein lipase from the surface of endothelial cells, resulting in a transient (30–120 minutes) reduction in serum triglycerides; however, triglycerides reaccumulate with long-term infusion.