Episode Details

Episode 122: Chronic Kidney Disease Overview

Future Dr. Westwood discusses with Dr. Arreaza the evaluation and treatment of CKD before renal replacement therapy. This is a broad overview of CKD.

Written by Daniel Westwood, MSIV, Ross University School of Medicine. Comments and editing by Hector Arreaza, MD.

Definition of CKD:

CKD is defined as abnormal kidney structure or function lasting more than three months with associated health implications. Indicators include albuminuria, urine sediment abnormalities, abnormal renal imaging findings, serum electrolyte or acid-base derangements, and decreased glomerular filtration rate (GFR).

Stages of CKD are based on GFR - CKD1 normal or high >90, CKD2 60-89, CKD3 <60 (3a 45-60), 3b (30-45), CKD4 <30, CKD 5 <15.

CKD can progress to advanced renal failure, end-stage renal disease, and even death; early detection is critical for initiating timely therapeutic interventions, limiting nephrotoxin exposure, preventing further reduction in GFR, and preparing for renal replacement therapy. 

Screening guidelines:

• Annual screening for CKD in pts with DM or HTN (AAFP and National Kidney Foundation)
• Other risk factors that may indicate screening: cardiovascular disease, older age, hx of low birth weight, and family hx of CKD.
• USPSTF recommends against screening asymptomatic adults
• American College of Physicians recommends against screening asymptomatic adults without risk factors.

How to screen? Multiple guidelines recommend at least annual screening with serum creatinine, urine albumin/creatinine ratio, and urinalysis (especially in diabetes mellitus, hypertension, and a history of cardiovascular disease).

Assessment of a patient with CKD:

1. Full medical history, including:
   • Exposure to potential nephrotoxins (NSAIDS, aminoglycosides, amphotericin B, IV contrasts.)
   • Review past and present blood pressure.
   • Dietary history: Western diet, high in calories, high in animal proteins, and low in fruit and vegetable content.
   • Recent weight gain is essential for CKD evaluation because weight gain may be a sign of fluid retention.
   • Obesity can be a risk for CKD.
2. Review of systems: Generalized weakness, decreased exercise tolerance, impaired cognitive function, decreased urination, foamy urine (proteinuria), anorexia, altered taste (dysgeusia), vomiting, skin changes, lower extremity edema, periorbital edema, shortness of breath, hallucinations (advanced stages).
3. Physical examination:
   • Clinical findings vary with the severity and chronicity of symptoms. It would be difficult to explain all the physical findings in a short time, but it is important to mention that some signs and symptoms may take years of chronic disease to develop, and sometimes patients may have CKD and not know it.
   • General exam: Chronically ill, tired, chronically ill, slow responses due to the accumulation of multiple toxins, including urea. Vitals: BP is elevated, or the patient is currently taking antihypertensives. The skin can be extremely dry, scaly, itchy, pale, or darker than usual for the patient, or you may see a rash.
   • Edema: pitting, bilateral, generalized, especially around the eyes.
   • Auscultation: Signs of fluid overload (bibasilar crackles, cardiac gallops, murmurs)
     • Signs of severe uremia: Uremic fetor (urine smelling), encephalopathy, uremic frost (urea crystals over the skin).
4. Laboratory:
   • Spot urine for albumin-to-creatinine ratio (ACR) to detect albuminuria
   • Serum creatinine to estimate glomerular filtration rate (GFR), serum electrolytes, fasting lipids, hemoglobin A1C
   • Urinalysis: High sensitivity for heavy proteinuria (> 300 mg in 24 hours, estimated from the spot urine protein/creatinine ratio)