Which of the following is NOT a cause of hyperkalemia?

Hyperkalemia, characterized by elevated levels of potassium in the blood, can be attributed to various causes. Increased dietary intake of potassium can contribute to hyperkalemia, especially if the kidneys are unable to excrete the excess potassium effectively. Cell wall destruction, which can occur in conditions like trauma, burns, or hemolysis, releases intracellular potassium into the bloodstream, leading to hyperkalemia. Renal failure is a significant cause of hyperkalemia because it impairs the kidneys' ability to excrete potassium effectively, resulting in its accumulation.

Dehydration, on the other hand, does not directly cause hyperkalemia. While dehydration can lead to a concentration of potassium due to a decreased volume of fluid, it is not considered a primary cause of increased potassium levels. Instead, dehydration often presents with hypokalemia due to shifts of potassium into cells or losses through gastrointestinal routes. Thus, it is the only option that does not directly lead to an increased potassium level in the serum.