Combination of circulating antilipoprotein lipase (Anti-LPL) antibody and heterozygous S172 fsX179 mutation of LPL gene leading to chronic hyperchylomicronemia.
BACKGROUND
Sporadic hyperchylomicronemia (type V hyperlipoproteinemia) results from complex interactions between genetic and environmental factors that often remain unknown.


METHODS
Upon investigation of a patient suffering from recurrent hypertriglyceridemic pancreatitis without family history or conventional secondary cause of dyslipidemia, we identified a previously unreported nonsense heterozygous lipoprotein lipase (LPL) gene mutation S172fsX179 associated with an antihuman LPL IgG.


RESULTS
This autoantibody partially inhibited wild-type LPL activity in vitro. Furthermore, the patient's plasma triglyceride concentrations were efficiently decreased under immunosuppressive treatment, and this was confirmed by sequential withdrawal/reintroduction tests.


CONCLUSIONS
We consider that this unique combination of a genetic defect and an autoimmune disease results in chronic major hypertriglyceridemia. Because immunosuppressive treatment can improve this dyslipidemia, assessment of anti-LPL autoantibody is worthwhile in unmanageable chronic major hypertriglyceridemia, even in the presence of a heterozygous LPL deficiency.
Pruneta-Deloche
Valérie
V
Unité Mixte de Recherche 585 Institut National de la Santé et de la Recherche Médicale/Institut National des Sciences Appliquées, Bâtiment Louis Pasteur, 20 avenue Albert Einstein, 69621 Villeurbanne cedex, France. valerie.pruneta-deloche@insa-lyon.fr
Marçais
Christophe
C
Perrot
Laurence
L
Sassolas
Agnès
A
Delay
Mireille
M
Estour
Bruno
B
Lagarde
Michel
M
Moulin
Philippe
P
D001323:Autoantibodies / Q000097:blood*; D002908:Chronic Disease; D002914:Chylomicrons / Q000097:blood*; D006579:Heterozygote; D006801:Humans; D006949:Hyperlipidemias / Q000209:etiology; D008071:Lipoprotein Lipase / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009154:Mutation
D001323:Autoantibodies; D002914:Chylomicrons; D008071:Lipoprotein Lipase