Instant Insights: Albuminuria

Healthier World with Quest Diagnostics
Date: November 3, 2025
Host: Dr. Mason Lasko

Episode Overview

This episode of Healthier World with Quest Diagnostics delivers a succinct, clinically focused overview of albuminuria as an early and valuable marker of kidney dysfunction. Dr. Mason Lasko and a medical expert co-host unpack why monitoring even small changes in albumin levels in urine can prompt early interventions to prevent progression to chronic kidney disease (CKD) and cardiovascular complications.

Key Discussion Points & Insights

1. Kidney Filtration and the Role of Albumin

• Healthy Kidney Function:
  • Kidneys filter about half a cup of blood per minute, selectively allowing small molecules out while retaining large proteins like albumin in the bloodstream.
    • Dr. Lasko (00:28):

      "Our nephrons... pull small molecules... out of the blood and into the urine, while keeping essential large proteins like albumin in the blood."

• Signs of Dysfunction:
  • When damaged (e.g., by diabetes, hypertension, or heart failure), the kidneys start leaking albumin, which can be detected in the urine—serving as a key early indicator of kidney injury and disease.

2. Testing and Terminology: Moving Beyond Micro and Macro

• Assessing Damage:
  • Any presence of protein, especially albumin, signals kidney damage.
    • Dr. Lasko (01:10):

      "If large proteins like albumin are starting to leak out into the urine, that can indicate that there is kidney damage."

• Updated Nomenclature:
  • Older distinctions ("proteinuria," "microalbuminuria," "macroalbuminuria") have fallen out of favor.
    • Dr. Lasko (01:58):

      "Differentiating using these particular terms is no longer recommended. Any level of albumin in the urine is now termed albuminuria."

3. Measuring Albuminuria: The Urine Albumin-Creatinine Ratio (UACR)

• Purpose of UACR:
  • Measures albumin relative to creatinine, accounting for variations in urine concentration.
    • Co-host (02:14):

      "Albumin is quantifiably measured in the urine using a urine albumin creatinine ratio..."

  • Creatinine is a small molecule always filtered, making it a reliable comparator for albumin measurement.
• Cut-off Values:
  • Moderate increase: UACR > 30 mg/g
  • Severe increase: UACR > 300 mg/g
    • Dr. Lasko (02:35):

      "Levels above 30 milligrams per gram indicate a moderate increase... above 300 milligrams per gram is severely increased..."

4. Clinical Significance of ‘Normal’ Albuminuria

• Even ‘Normal’ is Relative:
  • UACR < 30 mg/g is "normal," but high-normal values still confer increased risk for vascular and kidney issues.
    • Co-host (03:09):

      "A urine albumin creatinine ratio less than 30... still may indicate that these patients would benefit from additional evaluation and monitoring."

• Research Findings:
  • Elevated risk exists at high-normal levels, especially:
    • Men: UACR > 3.9 mg/g
    • Women: UACR > 7.5 mg/g
    • Co-host (03:50):

      "...males with an albumin creatinine ratio greater than 3.9 and females... greater than 7.5 have approximately three times greater risk for developing cardiovascular disease."

  • Even in absence of CKD by eGFR, albuminuria predicts faster progression and adverse outcomes.
    • Dr. Lasko (04:39):

      "Even normal levels... don't just predict cardiovascular dysfunction, but rather predict elevated risk for... kidney failure in people with CKD."

5. Albuminuria as an Early Intervention Opportunity

• Not Just a Threshold—A Continuum:
  • Risk increases across the spectrum of albuminuria, even below clinical cut-offs.
    • Dr. Lasko (05:18):

      "Albuminuria isn't a threshold to cross it's a continuum of vascular and renal risk that begins well before overt disease."

• Implications for Practice:
  • Any detection of albumin in urine can signal an opportunity for early intervention in preventing both CKD and cardiovascular diseases.

Memorable Quotes & Moments

• On clinical importance:
  Co-host (01:35):

  "Even before an EGFR starts to decline.", highlighting that albuminuria can be an earlier marker than declining eGFR.

• On terminology simplification:
  Dr. Lasko (01:58):

  "Protein in the urine means kidney damage... Any level of albumin in the urine is now termed albuminuria."

• On risk at high-normal levels:
  Dr. Lasko (03:21):

  "Values that don't reach the traditional cut points... are technically considered normal, but... carry increased risk."

• Clinical call-to-action:
  Dr. Lasko (05:18):

  "Albumin in the urine at any level is an opportunity for early intervention..."

Timestamps for Key Segments

• [00:28] Kidney filtration basics and the role of albumin
• [01:35] Early detection: albuminuria before eGFR decline
• [01:58] Terminology update: "albuminuria" as the universal term
• [02:14] Measuring albuminuria and the use of UACR
• [02:35] UACR risk thresholds explained
• [03:09] Clinical importance of monitoring high-normal UACR
• [03:50] Association between high-normal UACR and increased cardiovascular risk
• [04:39] Albuminuria as a predictor of kidney disease progression
• [05:18] Summary: Albuminuria as a continuum and intervention opportunity

Summary

This concise yet information-rich episode emphasizes that albuminuria is not just a threshold to cross, but a continuous marker of kidney and vascular risk. Even small increases within the normal range of albumin in urine provide early signals of potential kidney or heart issues—indicating that clinicians should view any level of albuminuria as a prompt for closer monitoring and possible intervention.

For more in-depth resources, the episode directs listeners to the Quest Diagnostics Clinical Education center.