Severe hypertriglyceridaemia — SCE Endocrinology MCQ

Correct answer: A — Familial chylomicronaemia from biallelic lipoprotein-lipase pathway impairment

The best answer is “Familial chylomicronaemia from biallelic lipoprotein-lipase pathway impairment”. Childhood extreme fasting triglycerides, recurrent pancreatitis and eruptive xanthomata without a secondary driver suggest autosomal-recessive failure of chylomicron clearance, most often involving LPL or its essential cofactors. “Heterozygous familial hypercholesterolaemia due to an LDLR variant” is less appropriate because familial hypercholesterolaemia causes marked LDL elevation and tendon xanthomata rather than chylomicronaemic pancreatitis “Secondary hypertriglyceridaemia from uncontrolled diabetes” is less appropriate because the stated glycaemic control removes the common secondary driver “Familial combined hyperlipidaemia as the principal possible inherited cause” is less appropriate because familial combined hyperlipidaemia is more variable and usually does not produce this childhood extreme phenotype “A bile-acid synthesis defect causing isolated LDL elevation” is less appropriate because the clinical problem is triglyceride-rich chylomicron clearance rather than isolated LDL metabolism

Reference: Endotext: Pancreatitis secondary to hypertriglyceridaemia. https://www.ncbi.nlm.nih.gov/books/NBK279082/