1 MetabolicUnit, Hospital Dona Estefânia, Centro Hospitalar de Lisboa Central, Lisbon, Portugal,
2 Instituto Nacional de Saúde Dr Ricardo Jorge, Lisbon, Portugal
12th International Congress of Inborn Errors of Metabolism, 3rd-6th September 2013, Barcelona (poster)
Introduction: Abetalipoproteinemia (ABL), a very rare disorder, is usually characterized by growth delay, diarrhea with steatorrhea and fat malabsorption, hepatomegaly, and neurological/neuromuscular symptoms. Patients show persistently low LDL cholesterol, triglycerides and apolipoproteins and acanthocytosis. It is inherited in a recessive manner (MTTP gene), whereas hypobetalipoproteinemia (HBL), a similar disorder, is a dominant disorder (APOB gene). Other genes have also been involved.
Case report: We describe a 14 year-old-girl who presented at the age of 16 months with failure to thrive, no history of chronic diarrhea, acantocythosis and mildly elevated transaminases and alkaline phosphatase. She also had very low levels of LDL- and HDL-cholesterol, triglygerides, apolipoproteins A1 and B. An endoscopy showed a white mucosa and the intestinal biopsies show enterocytes filled with numerous lipid droplets. She has very low vitamin E levels despite therapy with fat soluble vitamins. Molecular studies were negative for the MTP gene but others are pending.
Comments: The diagnosis of ABL/HBL should be considered in patients with low levels of cholesterol and triglycerides. The prognosis in this case seems better than described as the girl shows no clear worsening of symptoms over the time, no history of diarrhea or steatorrhea or retinitis pigmentosa on fundoscopy.
Keywords: Abetalipoproteinemia, hypobetalipoproteinemia