False estimates of elevated creatinine

Manpreet Samra1, Antoine C Abcar

  • 1Los Angeles Medical Center, CA, USA. manpreet.x.samra@kp.org

Insights

Elevated serum creatinine often signals reduced kidney function, but sometimes it’s inaccurate. Understanding causes of factitious creatinine elevation is crucial for correct diagnosis and patient care.

Area of Science:

  • Nephrology
  • Clinical Chemistry

Background:

  • Elevated serum creatinine is a common reason for nephrology consultation.
  • Serum creatinine elevation typically indicates a decreased glomerular filtration rate (GFR).
  • High creatinine levels are linked to increased cardiovascular mortality risk.

Observation:

  • Factitious elevation of creatinine can mislead clinical assessment.
  • These elevations may not reflect a true reduction in GFR.
  • Causes include increased creatinine production, assay interference, and decreased tubular secretion.

Findings:

  • Several factors can cause falsely elevated creatinine levels.
  • These factors can be categorized into three main groups.
  • Accurate GFR assessment requires considering these potential interferences.

Implications:

  • Recognizing factitious creatinine elevation is vital for accurate diagnosis.
  • It prevents unnecessary interventions and guides appropriate patient management.
  • Understanding these causes improves the reliability of kidney function tests.

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