Contact the Clinical Chemistry laboratory prior to collection for special tube. Patient must be fasting. Collect 3mL blood into cold VIP collection tube obtained from the Clinical Chemistry laboratory. The tube should be placed in a cold pack and delivered to the laboratory within 15 minutes of collection.
The VIP collection tubes are prepared by Clinical Chemistry staff (3 mL EDTA tube with 500KIU Aprotinin per mL of blood added e.g. 150 µL Aprotinin (conc 500,000KIU/50 mL) into a 3 mL EDTA tube. Prepared tubes are stored in the CSR refrigerator. These tubes are ready for use.
GENERAL NOTES
APPLICATION: Investigation of persistent unexplained diarrhoea.
INTERPRETATION: The presence of elevated levels of vasoactive intestinal peptide (VIP) in a patient with persistent severe diarrhoea associated with elevated levels of faecal sodium (secretory diarrhoea) indicates the presence of a tumour secreting VIP ("VIPoma"). These are usually located in the pancreas.
