Patient must have been fasting overnight
The sample needs to remain cold and be delivered to the laboratory immediately - SEND TO THE LABORATORY ON ICE . The sample should be separated immediately upon arrival at the laboratory.
Vasoactive intestinal peptide (VIP) is a neurotransmitter, widely distributed through the central and peripheral nervous system with the highest concentration occurring in the submucosal postganglionic intrinsic nerves of the intestinal tract. Normally VIP has a low blood concentration and does not change with meals.
Oversecretion of VIP from VIPomas is responsible for the rare Verner-Morrison or WDHA (watery diarrhoea, hypokalaemia, achlorhydria) syndrome. It is characterised by profuse watery diarrhoea, dehydration, hypotension, flushing, intestinal ileus, hypokalaemia, achlorhydria, hypomagnesaemia and metabolic acidosis. Hyperglycaemia and hypercalcaemia can also occur. While achlorhydria or hypochlorhydria distinguishes this diarrhoeal syndrome from gastrinoma, absence of this feature in some VIPoma patients is possible .
Pancreatic VIPomas (90%) are commonly located in body and tail of pancreas while extra-pancreatic VIPomas occur in the autonomic nervous system. VIPoma can coexist with gastrinoma in MEN I. Supraphysiological concentration of VIP inhibits gastrin release.
Due to the fluctuating VIP release from tumours coupled with its short half life, prefer blood collection at the time when patient is symptomatic. Care should be taken when injecting contrast media because VIP may be released.
References:
1. Holdcroft A Hormones and gut. British Journal of Anaesthesia 2000; 85(1): 58-68
2. Liddle RA Gastrointestinal hormones and neurotransmitters (chapter 1) in Sliesenger and Fordtran's Gastrointestinal and Liver disease - pathophysiology / Diagnosis/ management . 8th edition (2006) Feldman M, Friedman LS, Brandt LJ (eds). Saunders Elsevier, Philadelphia
3. Hammond PJ, Bloom SR Non-diabetic pancreatic endocrine disorders and multiple endocrine neoplasia. (chapter 12.10) in Oxford textbook of Medicine (4th edition, 2003) Warrell DA, Cox TM, Firth JD (eds) Oxford University Press Inc, New York
Emails to chemicalpathologist@adhb.govt.nz will receive priority attention from the on-call chemical pathologist.
If the query concerns a specific patient please include the NHI number in your email.
If email is not a suitable option, please contact the on-call chemical pathologist via Lablink (Auckland City Hospital ext. 22000 or 09-3078995).
Individual chemical pathologists may be contacted but will not be available at all times.
After-hours : contact Lablink (Auckland City Hospital ext. 22000 or 09-3078995) or hospital operator for on duty staff after hours.
Dr Samarina Musaad (Clinical Lead) : SamarinaM@adhb.govt.nz ext. 22402
Dr Cam Kyle: CampbellK@adhb.govt.nz ext 22052
Dr Weldon Chiu: WeldonC@adhb.govt.nz ext. 23427
Dr Campbell Heron: CHeron@adhb.govt.nz ext. 23427
Dr Sakunthala Jayasinghe: Sakunthala@adhb.govt.nz ext. 23427
| Sample collection |
EDTA tube, kept cold Sent to lab. immediately |
|
Sample preparation |
Keep cold Separate immediately Minimum volume >1mL, preferred >2mL |
|
Transport to LabPlus |
Send frozen (the sample is stable for up to 5 days at 4 o C) |