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A very rare syndrome caused by tumoral-inappropriate
vasoactive intestinal peptide secretion. Can be associated with multiple
endocrine neoplasias. Clinical aspect is a result of intensive diarrhea that
can lead to dehydration and severe hypokalemia.
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WDHA Syndrome; Water Diarrhea, Hypokalemia, Achlorhydria
Syndrome; WDHH Syndrome; Water Diarrhea, Hypokalemia, Hypochlorhydria
Syndrome; Diarrheagenic Syndrome; Pancreatic Cholera; Vipoma Syndrome.
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Described by John U. Verner and Ashton B. Morrison, both
American physicians, in 1958.
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3:10,000,000 people in the general population.
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This disease is caused by inappropriate secretion
of vasoactive intestinal peptide (VIP), usually secreted from non-beta islet
pancreatic cells in response to food containing fat, proteins, and alcohol.
It relaxes smooth muscles, resulting in a decrease of lower esophageal
sphincter pressure, relaxation of the gastric antrum and body, and
inhibition of gallbladder and intestinal circular muscle contraction. Extra
secretion of VIP will provide general manifestations such as vasodilatation,
positive inotropic action on the heart, increase in intestinal water and
electrolyte secretion, inhibition of gastrin and gastric acid secretion, and
stimulation of pancreatic secretion.
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Characterized by severe watery diarrhea and dehydration.
Diagnosis is confirmed by biochemistry (hypokalemia, hypochloremia, metabolic acidosis, high plasma
VIP levels; approximately two-thirds of patients have hypercalcemia and
50% are hyperglycemic), stool analysis (isotonic, alkaline, cultures negative), and
ultrasonography and CT imaging (dilated gallbladder, localization of tumors). Prostaglandin E and E2
hypersecretion can be associated.
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Hypermotility, watery diarrhea syndromes with
hypokalemia and hypochloremia or hyperchloremia, dehydration. Lethargy,
muscular weakness, nausea, vomiting, and abdominal pain are frequent. Fluid
secretion may exceed 3 to 5 L, with a loss of 200 to 300 mEq of potassium
daily. Some cases of VIPoma have included hypercalcemia, flushing, and
glucose intolerance. Ectopic primary sites, such as the liver and jejunum,
occur in approximately 10% of patients. In children, the VIPoma syndrome
is caused by either a ganglioneuroma or ganglioneuroblastoma. In adults, it
is caused by bronchiogenic carcinoma, pheochromocytoma, medullar thyroid
carcinoma, and retroperitoneal histiocytoma. Multiple endocrine neoplasia
type 1 can be associated (in MEN, hypercalcemia is frequent).
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Evaluate the extent of the
diarrhea (history, clinical
repercussion, laboratory investigations including natremia, kalemia,
calcemia, urea, creatinine, glycemia, arterial blood gas analysis). Also, the tumor
repercussion must be assessed because of the risk of obstruction of the duodenum or of the
biliary tract and of vascular erosion (radiography, CT, endoscopy).
Preoperative ECG should be done in cases of hypokalemia. Evaluate existence
and repercussion of flushing episodes (history, clinical, heart rate and
blood pressure measurement during flush).
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Preoperative hydration and electrolyte
correction is necessary based on the laboratory investigations. Elective surgical
procedures must be postponed until electrolytes and the intravascular fluid status
have been corrected. Vascular access can be extremely difficult and an emergency
route may be used (intraosseous, superior longitudinal sinus). Central venous
access using Seldinger technique should be avoided in cases of hypokalemia and
cardiac irritability. Glucose levels should be regularly ...