“Normal” lab values aren’t always normal for CKD physiology

by Robin Rose MD ©️

When I discovered that the normal range for phosphorus is not accurate for protecting CKD patients, a new portal of understanding opened for me that explained how come important and impactful problems get neglected in kidney care - often until too late in the game .

Phosphorus is a very long conversation in ckd - suffice it to say simply that when it goes awry in ckd - calcium may leach out of bones and get deposited in arteries. Both sides of that equation leave serious morbidity in the ckd community- metabolic bone disease and atherosclerosis are known hazards.

NORMAL RANGE OF SERUM PHOSPHORUS

2.5 to 4.5 mg/dL (0.81 to 1.45 mmol/L)

Despite the fact that phosphorus is a uremic toxin that starts its reign of terror in stage 2, and despite the fact that lifestyle fixes can make a big clinical difference, way too often it is not even ordered on routine testing and follow up !

And pathophysiological changes can begin even at phosphorus >3.5 mg/dL, particularly in CKD

Fibroblast growth factor [ FGF23 ] rises subtly when phosphorus exceeds ~3.5 mg/dL, even in early CKD. This hormone drives left ventricular hypertrophy, inflammation, and worsens CKD progression.

Parathyroid hormone [ PTH ] begins to increase in response to the phosphate burden, even if serum levels are still within “normal.”

Vascular smooth muscle cells exposed to phosphate levels above ~3.5 mg/dL begin to express osteogenic markers, triggering vascular calcification.

Studies show mortality curves in CKD patients begin to shift upward at serum phosphorus ≥3.5 mg/dL, especially later.

SO —::> 3.5 mg/dL may be a functional threshold — above this, subclinical pathology begins and why we aim for lower-normal phosphorus levels, even in early CKD.

This is why we have to establish new reference ranges for ckd safety.

In the same line of thinking, liver and pancreas disorders are not uncommon in ckd - realizing that we are most skilled and successful when we identify changes early enough for gentle intervention - to set things right.

The liver and pancreatic enzymes commonly collected on our panels include ::

▪️ALP - serum alkaline phosphatase

▪️GGT - gamma glutamyl transferase

▪️Amylase

▪️Lipase

▪️AST

▪️ALT

Some examples

▪️ALT

Normal range 7–55 IU/L

CKD normal 10–25 IU/L

Alert: >25–30 IU/L may be high for CKD

▪️AST

Normal range 10–40 IU/L

CKD normal. 10–20 IU/L

Alert: >25–30 IU/L may be significant

▪️GGT

Normal range 9–48 IU/L

CKD - Often low-normal

Alert : >40–50 IU/L may reflect hepatic or oxidative stress

▪️ALP

Normal range. 45–115 IU/L

CKD - May be elevated from bone turnover

Alert : >130–150 IU/L → evaluate bone vs liver isoenzymes

▪️LDH

Normal range 140–280 IU/L

CKD - Variable; can increase from hemolysis or catabolism

Alert: >250 in CKD may merit workup

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In CKD (especially stages 3–5), average ALT and AST values are 20–40% lower than in healthy populations.

A CKD patient with ALT 35 IU/L may be experiencing functional hepatic stress, even if it’s within lab “normal.”

These lab abnormalities in ckd can be due to:

• Pyridoxine (B6) deficiency

• Uremic toxin suppression

• Dilutional effects (especially in dialysis)

• Hepatic mitochondrial dysfunction

A “normal” ALP with elevated PTH may still reflect underlying renal osteodystrophy rather than hepatic pathology.

What to do about it?

Diligent lab follow up with a renology kidney success mind set [ that knows to educate and step in early] to use gentle lifestyle strategies that engage nature and self loving care - to derail and reroute hazards that chase away kidney success.

The ckd basics of diet exercise hydration sleep stress reduction toxin elimination harmony in nature and relations are the gracious beginnings.

Safe bioregulation to reverse epigenetic damage is a poignant choice- especially if we can start with early and subtle changes that we pick up with savvy about the labs. Here are a few thoughts ( refer to the book Renology Peptides for the depth needed to navigate with clinical excellence with these small peptides).

▪️Bonothyrk - parathyroid cytomax bioregulator can engage the phosphorus pathway - starting early is wise [ along with dietary mindfulness ]

▪️Svetinorm -liver cytomax bioregulator - plays a significant role in ckd

▪️Suprefort - pancreas cytomax bioregulator - in ckd pancreas support is a generous gift to protect and support metabolic health

The path to kidney success is paved with many kind intentions which can be combined with both education and intuitive efforts - to look for early and subtle changes that can be headed off at the pass before they attack. Knowing how to use the labs with CKD precision gives us all - patients and clinicians - a way to personalize and refine the outcomes. The art and clinical science of kidney success is at hand!

REFERENCES

1. Kendrick J Adv in CKD,2011

2. Rose R RENOLOGY Peptides 2025.

3. Manju M et al. Ind J Med Biochem 2019