title: Severe hypertriglyceridemia in a newborn with monogenic lipoprotein lipase deficiency: an unconventional therapeutic approach with exchange transfusion.
abstract: Severe hypertriglyceridemia (sHTG) (plasma triglyceride level > 10 mmol/L) due to lipoprotein lipase (LPL) deficiency is a known risk factor for acute pancreatitis. A 23-day-old male with sHTG was admitted to the Neonatal Intensive Care Unit for plasmapheresis being at high risk for acute pancreatitis. Given the potential hazard of an extracorporeal technique in a very young infant, we decided to perform an exchange transfusion (ET), a procedure widely used by neonatologists and less invasive than plasmapheresis. ET led to a dramatic reduction in plasma triglyceride level, from 93.2 to 3.8 mmol/L at the end of the procedure, without adverse events. The subsequent administration of a special formula low in fat and high in medium-chain triglycerides was effective in keeping fasting plasma triglyceride level below 5.6 mmol/L during the first 5 months of life. The sequence of LPL gene revealed that the patient was apparently homozygous for a novel nucleotide deletion (c.840delG) in exon 6 leading to a premature termination codon (p.N281Mfs*23). However, family studies revealed that while the patient's mother was heterozygous for this mutation, the father was heterozygous for a novel deletion eliminating the whole LPL gene. The patient therefore turned out to be a compound heterozygous for two LPL gene mutations predicted to abolish LPL activity. This is the first case of sHTG treated with ET in a neonate reported in the literature. ET appears to be a safe procedure, alternative to plasmapheresis, to prevent acute pancreatitis in young infants with sHTG due to LPL deficiency.
authors.affiliation: NICU, Department of Clinical Sciences and Community Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Via Commenda 12, 20122, Milan, Italy, lorenza.pugni@mangiagalli.it.
authors.forename: Lorenza
authors.initials: L
authors.lastname: Pugni
authors.forename: Enrica
authors.initials: E
authors.lastname: Riva
authors.forename: Carlo
authors.initials: C
authors.lastname: Pietrasanta
authors.forename: Claudio
authors.initials: C
authors.lastname: Rabacchi
authors.forename: Stefano
authors.initials: S
authors.lastname: Bertolini
authors.forename: Cristina
authors.initials: C
authors.lastname: Pederiva
authors.forename: Fabio
authors.initials: F
authors.lastname: Mosca
authors.forename: Sebastiano
authors.initials: S
authors.lastname: Calandra