What causes hypokalemia in VIPoma?
What causes hypokalemia in VIPoma?
The causes of hypokalemia are associated with aldosterone synthesis, VIPoma-induced chronic diarrhoea, or direct potassium excretion by enterocytes (14). Hypokalemia may result in manifestations, such as muscle weakness, flaccid paralysis, respiratory distress and changes in the ECG (flattened T-waves).
Why does VIPoma cause acidosis?
Hypokalemia and hyperchloremic metabolic acidosis occur due to a large amount of GI loss and bicarbonate wasting. Hypochlorhydria occurs secondary to the direct gastric acid inhibitory effect of VIP.
How is VIPoma diagnosed?
Tests used to diagnose a VIPoma may include blood tests (including VIP level), imaging studies such as a CT scan or MRI , and examination of a stool sample. Unfortunately, even though these tumors are slow-growing, the majority of VIPomas are metastatic (have spread to other parts of the body) at the time of diagnosis.
Is VIPoma curable?
Outlook (Prognosis) Surgery can usually cure VIPomas. But, in one third to one half of people, the tumor has spread by the time of diagnosis and cannot be cured.
Why does VIPoma cause diarrhea?
This occurs as a result of VIP binding to intestinal epithelial cells, thereby upregulating cAMP and leading to secretion of electrolytes into the bowel lumen, causing profuse watery diarrhea [2]. Most patients experience diarrhea (89%), weight loss (72%), and hypokalemia (67%) [7].
How common is VIPoma?
VIPomas are often diagnosed in adults, most commonly around age 50. Women are more likely to be affected than men. This cancer is rare. Each year, only about 1 in 10 million people are diagnosed with a VIPoma.
Is VIPoma hereditary?
This is often a genetic condition that runs in families. VIPoma: A type of neuroendocrine pancreatic tumor that secretes vasoactive intestinal polypeptide (VIP).
Does VIPoma cause metabolic acidosis?
A VIPoma is a neuroendocrine neoplasm (NEN) secreting VIP, causing severe watery secretory diarrhea, which can result in hypokalemia and metabolic acidosis.
Where are Vipomas located?
VIPoma is a very rare cancer that usually grows from cells in the pancreas called islet cells. The pancreas is an elongated, tapered gland that is located behind the stomach and secretes digestive enzymes and the hormones insulin and glucagon.
What are the diagnostic criteria for VIPoma?
Diagnosis of VIPoma is made in patients with secretory diarrhea usually greater than 3.0 liters per day with a serum VIP level around 250 to 500 pg/ml (reference range is less than 190 pg/ml). Secretory diarrhea has a low fecal osmotic gap of less than 50 mOsm/kg. Blood chemistry tests (basic or comprehensive metabolic panel).
What are normal plasma VIP levels in VIPoma?
A normal plasma VIP level is 20-30 pmol/L or less, as determined by radioimmunoassay. VIP levels in patients with VIPoma often reach 160-250 pmol/L or higher. VIP levels should be drawn after fasting. [ 17]
What are the symptoms of a VIPoma in the stomach?
Persons with vipoma will experience the following symptoms and signs: 1 Nausea 2 Abdominal cramping and pain 3 Facial redness 4 Diarrhea 5 Losing of weight 6 Dehydration 7 Hypokalemia or low potassium level 8 Achlorhydria or low acid stomach 9 Appetite is reduced 10 Lethargy
What is a VIPoma of the pancreas?
A vipoma is a non-beta pancreatic islet cell tumor secreting vasoactive intestinal peptide (VIP), resulting in a syndrome of watery diarrhea, hypokalemia, and achlorhydria (WDHA syndrome). Diagnosis is by serum VIP levels. Tumor is localized with CT and endoscopic ultrasound. Treatment is surgical resection.