Chemical Pathology

Notes

Routine lipid tests available include:

  • Total cholesterol
  • Triglyceride
  • HDL-cholesterol
  • LDL-cholesterol (calculated; requires a fasting blood sample)
  • Total cholesterol: HDL-Cholesterol ratio
  • non HDL-cholesterol

Requesting guidelines:

  • Initial CVD risk-assessment and monitoring of statin medication in patients at increased risk of CVD - cholesterol, HDL-cholesterol, cholesterol:HDL-cholesterol ratio and non HDL-cholesterol (fasting not required) (Non-Fasting Cholesterol Test)
  • Baseline pre-treatment profile in the NICE guideline - cholesterol, HDL-cholesterol, non HDL-cholesterol, cholesterol:HDL-cholesterol ratio and triglyceride (fasting not required) (Full Non-Fasting Lipid Profile)
  • Follow up investigation of hypertriglyceridaemia or investigation of possible familial hypercholesterolaemia identified at screening - chiolesterol, HDL-cholesterol, cholesterol:HDL-cholesterol ratio, non HDL-cholesterol, triglycerides, LDL-cholesterol (12 - 14 hour fast required) (Full Fasting Lipid Profile)

LDL-cholesterol is not reported in non-fasting samples or if triglyceride levels are >4.5mmol/L.

HDL-cholesterol is not reported if triglyceride levels are >20mmol/L.

Cholesterol levels fall within 24 hours of an acute myocardial infarction and return to pre-infarction levels over the following three months. Therefore a normal cholesterol result during this period does not necessarily exclude hypercholesterolaemia.

Sample requirements

For a Full Fasting Lipid Profile, a blood sample collected after a 12 - 14 hour fast is required.

For adults, blood taken into a 5mL gold top tube (or rust top for the Acute Unit)

5ml gold tube

For children, blood taken into a 3.5mL rust top tube

3.5ml rust top tube

For neonates, blood taken into a 0.8mL minicollect lithium heparin tube

0.8ml minicollect tube

Storage/transport

Send at ambient temperature to the laboratory. If unavoidable, samples can be stored refrigerated overnight.

Required information

Relevant clinical details including current lipid medication; any family history. Please state whether patient fasting or not at time of venepuncture.

Turnaround times

The assays are run throughout the day and night.

The in-lab turnaround time is less than 24 hours.

Reference ranges

Reference range for fasting serum triglyceride: 0.6 - 1.9 mmol/L

Reference ranges are not quoted for the other lipid profile parameters, rather results should be assessed in terms of the overall risk to the patient.

Further information

Lab Tests Online

Cholesterol monograph of the Association for Clinical Biochemistry and Laboratory Medicine

NICE Lipid Modification Guidelines 2014

GHNHSFT Guidelines: Guidelines on Statin Prescribing in Prevention of CVD.