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AKI Staging (KDIGO)Anion Gap + Delta-Delta CKD Stage (KDIGO)Creatinine Clearance Electrolyte & Free Water FENa FEUrea KFRE — Kidney Failure Risk Kt/V Dialysis Sodium Correction UACR UPCR Urea Reduction Ratio (URR) Calculator Uric Acid & FEUA Urinary Anion Gap Winter's Formula eGFR (CKD-EPI)

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Recent Journal Updates

Drug SafetyJun 2, 2026

Gabapentin and Pregabalin Use in First Trimester of Pregnancy and Risk of Specific Congenital Anomalies: An IMI ConcePTION European Case-Malformed Control Study

Clinical Context

We think this might be relevant to the clinical guidance for Urinary Anion Gap (UAG).

Clinical Pharmacology TherapeuticsMay 29, 2026

Hepatic CYP1A2 Activity in Adolescents with and without Obesity Assessed by the Urinary Paraxanthine‐to‐Caffeine Metabolic Ratio: A Pharmacokinetic Study

Clinical Context

We think this might be relevant to the clinical guidance for Urinary Anion Gap (UAG).

DiabetologiaMay 22, 2026

Age-related patterns of cardiometabolic risk factors for complications in type 2 diabetes

Clinical Context

We think this might be relevant to the clinical guidance for Urinary Anion Gap (UAG).

Urinary Anion Gap

UAG Calculator

Urinary Anion Deviation

Urine Electrolytes

Urine Na⁺

Urine K⁺

Urine Cl⁻

Diagnostic Rule

Estimates Urinary Ammonium excretion (NH₄⁺). Negative UAG = High excretion; Positive UAG = Low excretion.

Etiology Resolver

Enter urine electrolytes to differentiate Renal vs Extra-renal acidosis.

Guidelines & Evidence

Verified

Last Review: 2026

When to Use

When to Use

Normal Anion Gap Metabolic Acidosis (NAGMA) — after HAGMA has been excluded.

Differentiating Renal Tubular Acidosis (RTA) from extra-renal (GI) causes of NAGMA.

Persistent NAGMA in the absence of obvious GI losses.

Investigating hyperchloraemic acidosis post-saline resuscitation vs. true RTA.

The Clinical Question It Answers

In NAGMA, are the kidneys excreting enough acid (NH₄⁺)? A negative UAG confirms the kidneys are responding correctly — the problem is extra-renal. A positive UAG indicates the kidneys are failing to acidify the urine — pointing to Renal Tubular Acidosis.

Related Scores in Practice

In clinical practice, this assessment is frequently evaluated alongside other validated measures. Depending on the patient's presentation and specific diagnostic requirements, you may also need to utilize the Anion Gap Calculator, Winter's Formula, FENa or the FEUrea to formulate a comprehensive care plan.

Last Comprehensive Review: 2026

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