Eubicarbonatemic Hydrogen Ion Retention and CKD Progression.

Area of Science:

• Nephrology
• Internal Medicine
• Acid-Base Physiology

Background:

• Hypobicarbonatemic metabolic acidosis is linked to chronic kidney disease (CKD) progression.
• Current guidelines recommend alkali therapy for CKD patients with serum bicarbonate <22 mEq/L.
• Many CKD patients, even with normal bicarbonate, may have unmeasured hydrogen ion retention.

Purpose of the Study:

• To review the concept of eubicarbonatemic hydrogen ion retention (subclinical metabolic acidosis) in CKD.
• To explore its prevalence, pathophysiology, clinical course, and potential biomarkers.
• To emphasize the need for trials on alkali therapy for eubicarbonatemic CKD.

Main Methods:

• Literature review of studies on metabolic acidosis in CKD.
• Analysis of existing data on serum bicarbonate and hydrogen ion retention.
• Discussion of potential biomarkers for subclinical metabolic acidosis.

Main Results:

• Subclinical metabolic acidosis is likely prevalent in CKD patients with normal serum bicarbonate.
• This condition may contribute to CKD progression.
• Limited data suggest potential benefits of alkali therapy in eubicarbonatemic CKD.

Conclusions:

• Eubicarbonatemic hydrogen ion retention represents a significant, underrecognized aspect of CKD.
• Alkali therapy may be beneficial for a broader CKD population than currently indicated.
• Definitive clinical trials are urgently required to validate this hypothesis and potentially shift treatment paradigms.