Renal Function and Disease Quiz

Study Notes

The tutorial covers renal health issues, including general renal starting questions, dosage adjustment in renal impairment, causes and management of acute renal failure (ARF), differences between ARF and chronic kidney disease (CKD), management of CKD, and renal replacement therapies.
Key issues to be reviewed include:
- General renal starting questions (e.g., kidney function, GFR regulation, GFR estimation)
- Dosage adjustment for renal impairment
- Causes and management of ARF
- Differences between ARF and CKD
- Management of CKD
- Renal replacement therapies
Note: Lecture materials should also be reviewed as the 2-hour tutorial cannot cover all key points.
Renal impairment degrees:
- Mild: 25-50 ml/min
- Moderate: 10-25 ml/min
- Severe: <10 ml/min
Renal failure types:
- Acute renal failure (ARF)
- Chronic renal failure (CRF), also known as Chronic Kidney Disease (CKD)
- End-stage renal failure: Typically treated with renal transplant or dialysis

Key functions of the kidneys include elimination of wastes, fluid balance, electrolyte balance, endocrine homeostasis (K+, Na+, H₂O), and elimination/clearance of drugs, drug metabolites and nitrogenous waste products (urea, etc.), erythropoiesis, acid-base balance, vitamin D activation.
How these functions are affected by acute or chronic renal failure
GFR regulation
GFR estimation methods

Categorizing renal impairment (from a dosage adjustment perspective)
Estimating renal function (e.g., creatinine clearance (CrCl))
Limitations of CrCl calculations in certain situations
Considerations when prescribing medications in renal impairment (e.g., nephrotoxicity, drug removal mechanisms, potential drug metabolites, how renal impairment affects the drug, dialysis impact, dose selection)

Cockcroft-Gault Equation (CrCl) formula (based on patient age, weight, and serum creatinine level).
Estimated Glomerular Filtration Rate (eGFR) calculation methods.
Considerations for the use of these equations.
Limitations regarding both formulas.

Patient information (62 years, 70kg, 160cm, SCr = 210 micromol/L)
Organism: Streptococcus pyogenes, sensitive to benzylpenicillin and vancomycin
CrCl Calculation and degree of impairment
Drug Considerations for Mr. AB (nephrotoxicity, removal mechanisms, metabolites, etc).
Dose adjustments for Benzylpenicillin, based on GFR/CrCl

Incidence rates (70-140 cases/1,000,000 general population; substantial hospitalization rates; ICU even higher)
- Significant cost implications.
Prognosis factors, including long-term dialysis dependence and chronic kidney disease risk
Variables impacting mortality
Clinical features (such as nausea/vomiting, peripheral edema, breathlessness, itching, weakness, pericarditis, vague mental status, oliguria, and convulsions)
Pathophysiology of AKI (pre-renal, intrarenal, post-renal)

AKI: Sudden onset, usually reversible, focuses on excretory and homeostatic functions
CKD: Gradual onset, irreversible/progressive, involving excretory, homeostatic functions, and endocrine abnormalities

Clinical assessment: Identify recent changes in clinical biochemistry
- History of prolonged vague ill-health, nocturia, or pruritis
Renal ultrasound to assess kidney size.
Look for anaemia, which can be a symptom of CKD.
Evidence of long-standing renal bone disease (e.g., hyperparathyroidism) strongly suggests CKD.

Leading causes (diabetes, hypertension, glomerulonephritis, nephrotoxicity, reflux nephropathy, polycystic kidney disease)
Controlling factors to slow renal decline (control protein load, hypertension, dyslipidemia, blood glucose levels)

Yellow Action Plan: eGFR ≥ 60 mL/min/1.73m² with microalbuminuria or eGFR of 45-59 mL/min/1.73m² with normoalbuminuria
Orange Action Plan: eGFR 30–59 mL/min/1.73m² with microalbuminuria or eGFR 30-44 mL/min/1.73m² with normoalbuminuria
Red Action Plan: eGFR < 30 mL/min/1.73m² or macroalbuminuria - preemptive transplantation potentially indicated

Specific management strategies exist for complications of CKD (Metabolic Acidosis, Hyperuricaemia, Bleeding and Infections, Gastrointestinal problems, Dermatological problems, Neuromuscular complications).