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AKI Staging (KDIGO)Anion Gap + Delta-DeltaCKD Stage (KDIGO)Creatinine ClearanceElectrolyte & Free WaterFENaFEUreaKFRE — Kidney Failure RiskKt/V DialysisSodium CorrectionUACRUPCRUrea Reduction Ratio (URR) CalculatorUric Acid & FEUAUrinary Anion GapWinter's FormulaeGFR (CKD-EPI)
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Specialty Module

Nephrology

eGFR equations, electrolyte correction, and kidney failure risk models.

17

Clinical Tools

6

Clinical Domains

16

Conditions Covered

5

Guidelines Referenced

Clinical Context

CKD staging with eGFR equations

Chronic kidney disease (CKD) staging is based on estimated glomerular filtration rate (eGFR) using the CKD-EPI 2021 equation, which no longer includes a race coefficient. Accurate eGFR calculation guides CKD classification, medication dosing, and nephrology referral timing according to KDIGO guidelines.

Kidney failure risk prediction with KFRE

Kidney failure risk prediction using the Kidney Failure Risk Equation (KFRE) provides 2-year and 5-year risk estimates for progression to end-stage kidney disease, incorporating eGFR, albuminuria, age, sex, and diabetes status. A 5-year risk of >5% warrants nephrology referral and >20% warrants preparation for renal replacement therapy.

Acid-base and electrolyte management in kidney disease

Acid-base and electrolyte management in nephrology spans anion gap interpretation for metabolic acidosis, delta-delta ratio analysis for mixed acid-base disorders, and calculated serum osmolality for toxic alcohol screening. Electrolyte correction calculators for sodium, potassium, and calcium guide safe repletion in acute and chronic kidney disease.

Conditions & Domains

Clinical Conditions Covered

Chronic Kidney Disease
Acute Kidney Injury
End-Stage Renal Disease
Metabolic Acidosis
Metabolic Alkalosis
Hyponatremia
Hyperkalemia
Hypokalemia
Hypercalcemia
Hypocalcemia
Nephrotic Syndrome
Glomerulonephritis
Hypertensive Nephropathy
Diabetic Nephropathy
Renal Artery Stenosis
Nephrolithiasis

Evidence Base

Referenced Guidelines & Standards

KDIGO CKD Guidelines
KDIGO AKI Guidelines
NKF KDOQI Guidelines
ERA-EDTA Guidelines
NICE CKD Guidelines

Toolkit

17 Clinical Calculators

Peer-Reviewed
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)

About

Nephrology

Nephrology requires constant calculation. We provide the latest CKD-EPI equations, the KFRE for kidney failure risk, and a full suite of electrolyte and acid-base tools for acute and chronic renal care.

Covered Areas

  • eGFR & CKD Staging
  • Kidney Failure Risk
  • Acid-Base & Anion Gap Analysis
  • Electrolyte Correction
  • AKI Differential Diagnosis
  • Dialysis Adequacy

All tools are based on published clinical evidence. Results should be interpreted alongside individual patient presentation and current institutional guidelines.