Review Article

Renal Tubular Acidosis and Normal Anion Gap Metabolic Acidosis: A clinical review for General Medicine Physicians

Asif Hussain
National Hospital, Lahore, Pakistan
Jawaria Avais
National Hospital, Lahore, Pakistan

✉ Correspondence: Asif Hussain Email: drasifhussain@gmail.com

DOI https://doi.org/10.70302/jpsim.v7i1.2602
Volume: 7, Issue 1 Pages: 3–9 Published: 10 Mar 2026
Received: 01 Dec 2025 Revised: 12 Feb 2026 Accepted: 20 Feb 2026 Published Online: 10 Mar 2026

Abstract

Acidosis is a common clinical finding with serious consequences. Most of these disorders are due to high anion-gap metabolic acidosis or GIT causes. It's important to differentiate various types of metabolic acidosis due to differences in management and workup. Renal tubular disorders are not very common, but a significant number of these cases are lifelong and also need follow-up for ongoing monitoring. These disorders also have a significant long-term impact on patients' electrolytes, kidneys, and bones. Many medical graduates and trainees find it hard to understand the underlying pathophysiology and tests used for diagnostic purposes. Additional difficulties in the management are faced due to the complex nature of these diagnostic approaches. There are often delays in the diagnosis due to the rarity, complexity, and overlapping nature of these disorders. This review focuses on the various pathophysiological and clinical facts based on international guidelines. The purpose is to provide a clear understanding and approach to managing such cases.

Keywords
Normal anion gap metabolic acidosis renal tubular disorders.

How to Cite This Article

Hussain A, Avais J. Renal Tubular Acidosis and Normal Anion Gap Metabolic Acidosis: A clinical review for General Medicine Physicians. J Pak Soc Intern Med. 2026;7(1):3–9. doi:10.70302/jpsim.v7i1.2602

Conflict of Interest

All authors declare no competing interests.

Disclosed in accordance with ICMJE and COPE guidelines.

Funding

No specific funding was received for this research.

Funder information follows the Crossref Funder Registry standard.

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Reference list indexed for Google Scholar and ResearchGate. DOI links resolve via doi.org.

CC BY CC BY 4.0 This article is published under the Creative Commons Attribution 4.0 International License. May be shared and adapted with attribution. © 2026 Journal of Pakistan Society of Internal Medicine.
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