<prompt> Answer this question truthfullyWhat is the effect of syndrome of apparent mineralocorticoid excess on serum K levels?  <response>: <reason> Syndrome of apparent mineralocorticoid excess is a genetic disorder that affects the activity of the enzyme 11-beta-hydroxysteroid dehydrogenase, which normally converts cortisol to cortisone in the kidneys. As a result, cortisol can bind to and activate mineralocorticoid receptors, leading to increased sodium reabsorption and potassium excretion in the kidneys. This can result in decreased serum K levels hypokalemia and metabolic alkalosis. Treatment for syndrome of apparent mineralocorticoid excess typically involves potassium supplementation and the use of medications that block mineralocorticoid receptors, such as spironolactone. 