Diagnosis and stabilisation of familial chylomicronemia syndrome in two infants presenting with hypertriglyceridemia-induced acute pancreatitis.

Familial chylomicronemia syndrome (FCS) is a rare disorder of triglyceride (TG) metabolism caused by loss of function variants in one of five known canonical genes involved in chylomicron lipolysis and clearance- LPL , APOC2 , APOA5 , LMF1 , and GPIHBP1 . Pathogenic variants in LPL , which encodes the hydrolytic enzyme lipoprotein lipase, account for over 80%-90% of cases. FCS may present in infancy with hypertriglyceridemia-induced acute pancreatitis and is challenging to manage both acutely and in the long-term. Here, we report our experience managing two unrelated infants consecutively diagnosed with hypertriglyceridemia-induced acute pancreatitis caused by LPL deficiency. Both had elevated TGs at presentation (205 and 30 mmol/L, respectively) and molecular genetic testing confirmed each infant carried a different homozygous pathogenic variant in the LPL gene, specifically, c.987C>A (p.Tyr329Ter) and c.632C>A (p.Thr211Lys). The more severely affected infant had cutaneous xanthomata, lipemia retinalis and lipemic plasma at presentation, and required management in an intensive care setting. Acute stabilisation was achieved using insulin and heparin infusions together with the iterative implementation of a fat-restricted diet, low in long chain triglycerides (LCT) and supplemented with medium chain triglycerides (MCT). In both cases, provision of adequate caloric intake (~110-120 kcal/kg/day) was also found to be important for a sustained TG reduction during the acute phase of management. In summary, a high index of suspicion is required to diagnose FCS in infants with hypertriglyceridemia-induced acute pancreatitis, management of which can be challenging, highlighting the need for more evidence-based recommendations.
Competing Interests: Oliver Heath, Brooke Allender, Joel Smith, Lucy Spencer, Elena Savva, Thomas H. Rozen, Natasha J. Brown, Elizabeth G. Bannister, Maureen S. Evans, Sharmila Kiss, and Joy Yaplito‐Lee have approved the manuscript and declare that they have no conflict of interest. They did not receive reimbursements/fees/funds/salaries from an organisation that may in any way gain or lose financially from the results reported in the reviewed manuscript in the last 5 years and have no other competing financial or non‐financial interests, as outlined in the JIMD Conflict of Interest form.
(© 2024 The Authors. JIMD Reports published by John Wiley & Sons Ltd on behalf of SSIEM.)