An overview of evaluating patients for familial chylomicronemia syndrome (FCS)

Laboratory findings

Severe, treatment-refractory hypertriglyceridemia is the principal laboratory finding.12,14

The blood of patients with FCS can have a creamy or milky appearance due to the presence of large amounts of chylomicron particles.14 After mild centrifugation or storage at 4°C for 24 hours, the chylomicrons appear as a creamy supernatant layer in serum.14

Patients with FCS often have low levels of other lipoproteins such as fasting LDL-C, VLDL-C, and HDL-C, and correspondingly low apoliprotein B levels.30

Clinical features

FCS can be recognized by its clinical and laboratory features, though genetic testing is recommended to help confirm a diagnosis.4

Severe treatment-refractory hypertriglyceridemia12,14

  • Fasting TG > 880 mg/dL (10 mml/dL), AND
  • Minimal or no response to fibrates, niacin, omega-3 fatty acids, or statins

Clinical history14

  • History of acute pancreatitis, OR
  • History of recurrent, unexplained abdominal pain

Absence of secondary causes4

  • Diet, lifestyle, and/or medications associated with elevated triglyceride levels

People with FCS often have normal or low body mass due to severe dietary restrictions.30