A 77 year old female is brought to the emergency room with symptoms of nonspecific abdominal discomfort

A 77 year old female is brought to the emergency room with symptoms of nonspecific abdominal discomfort.She has no history of anorexia,fever,chills or weight loss.

On physical examination,the vital signs are normal,the abdomen is soft and nontender with no masses or organomegaly palpated.Abdominal X-rays show lots of stool in the colon,but no free air or air-fluid levels.Laboratory investigations reveal an amylase of 150 U/L(25–125 U/L) and the rest of her biochemistry and complete blood count are normal.

Amylase accumulates in the setting of renal failure and thus becomes less valuable diagnostic test ( false positive).