Transporters affecting biochemical test results: Creatinine-drug interactions

Area of Science:

• Nephrology
• Pharmacology
• Biomarker Research

Background:

• Creatinine is a waste product primarily eliminated by the kidneys.
• Serum creatinine (SCr) and creatinine clearance are commonly used indicators of kidney function and acute kidney injury (AKI).
• The kidney's elimination of creatinine involves both glomerular filtration and active tubular secretion.

Purpose of the Study:

• To discuss the specific transporters responsible for creatinine renal clearance.
• To evaluate the limitations of using serum creatinine as a reliable biomarker for detecting kidney damage, particularly in the context of drug-induced effects.
• To differentiate between benign and pathological changes in SCr levels.

Main Methods:

• Review of existing literature on renal creatinine transport mechanisms.
• Analysis of studies investigating drug interactions with creatinine transporters.
• Examination of the physiological basis for creatinine elimination in the kidneys.

Main Results:

• Creatinine elimination is mediated by specific renal transporters, not solely glomerular filtration.
• Inhibition of these active transport mechanisms can lead to elevations in SCr levels.
• These drug-induced SCr increases may be reversible and not indicative of actual kidney damage.

Conclusions:

• Serum creatinine levels can be affected by factors other than glomerular filtration rate, such as active tubular transport.
• Relying solely on SCr as a marker for acute kidney injury may be misleading due to potential drug-induced elevations.
• Understanding creatinine transport is crucial for accurate interpretation of kidney function tests and avoiding misdiagnosis of kidney damage.