Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (1279 page)

   
Normal range:
0–7 mg/day.

   Use

   Screening for catecholamine-secreting tumors in children when accompanied by HVA

   Supporting a diagnosis of neuroblastoma

   Monitoring neuroblastoma treatment

   Interpretation

Increased In

   Pheochromocytoma

   Paraganglioma

   Neuroblastoma

   Limitations

   Patients should avoid salicylates, caffeine, phenothiazine, and antihypertension agents, as well as coffee, tea, chocolate, and fruit (especially bananas and any vanilla-containing substances for 72 hours prior to collection).

   Some neuroblastoma patients are positive for urinary homovanillic acid abnormality but do not excrete increased VMA. Twenty to thirty-two percent of patients with neuroblastoma do not have elevation of VMA. Many have other laboratory abnormalities such as increased metanephrines, HVA, or dopamine.

VASOACTIVE INTESTINAL POLYPEPTIDE (VIP)

   Definition