Which of the following is a sign of acidosis in a patient with renal issues?

Decreased bicarbonate levels indicate an accumulation of acid in the bloodstream, which is a hallmark sign of acidosis. In patients with renal issues, the kidneys may not be able to effectively excrete hydrogen ions or reabsorb bicarbonate, leading to a reduction in bicarbonate concentration. This imbalance results in a lower blood pH, confirming a state of acidosis.

While elevated blood urea nitrogen levels and reduced creatinine clearance may indicate impaired kidney function, they do not directly signify acidosis. Normal blood pH levels would indicate a normal acid-base balance, which contradicts the presence of acidosis. Therefore, decreased bicarbonate levels stand out as a clear indicator of acidosis in the context of renal dysfunction.