CHRONIC RENAL DISEASE

Chronic renal failure is defined as a reduction for over 3 months of the filtration of waste with any evidence of kidney damage (in early stage), which glomerular filtration rate: GFR < 60 ml/min according to Gault and Cockcroft, or 60 ml/mn/1.73m2 as MDRD formula

Cockroft-Gault equation
Cr. Cl (mL/min) = (140 – age) x weight / 72 x S. Cr (x 0.85, if female)

Risk factors

Etiology

Glomerular nephropathies (50%)
• Diabetic Nephropathy: Type 2 diabetes
• Primitive chronic glomerulonephropathy: Berger's disease (IgA GN)
• Secondary chronic glomerulonephropathy: SLE, amylose
Vascular Nephropathy (20%): Nephroangiosclerosis

Tubulo-interstitial nephropathy (10%): Reflux nephropathy

Hereditary nephropathy (10%): Autosomal dominant polycystic kidney disease
Undetermined etiology (> 10%)

Pathophysiology-The biologic basis for disease in adults

Diagnosis

Confirming renal failure

plasma creatinine
creatininemia > 115μM → calculate the clearance to estimate GFR

GFR estimated by clearance: Cockroft and Gault formula

Chronic renal disease feature:

• Kidney Failure > 3 months
• History of kidney disease or elevated creatinine
• Decrease kidney size
• Anemia normocytic normochromic non-regenerative, due to erythropoietin deficiency
• Hypocalcemia

Nevertheless, there are some exceptions
CKD with normal kidney size or increased: Diabetes/ Amyloidosis/ Bilateral hydronephrosis/ Autosomal dominant polycystic kidney disease

CKD with normocalcemia or increased:Myeloma and bone metastases/ CKD with other causes of hypercalcemie

Stage of CKD

Ferri's Clinical Advisor 2015

From 3B, the prognostic is severe

Clinical examination

History: Diabetes, HTN / family history of renal disease

Sign & Symptom: Cramps (uremia), asthenia, anemia

Physical exam related to etiology

• Glomerular nephropathy: Dipstick, edema, extra-renal signs
• Vascular nephropathy: Pulse, murmurs, sounds
• Tubular-interstitial nephropathy: Chronic retention, bladder enlargement, rectal touch
• Autosomal dominant polycystic kidney disease: palpation is lumbar region

Investigation

Creatininemia with creatinine clearance (MDRD / Cockroft) to confirm renal failure
Etiology finding
Urinalysis with urinary sediment
Proteinuria of 24h urine collection
Glycemia and HbA1c
Ultrasound

Evaluate severity
CBC
Uremia
Blood Chemistry: Na, K, Cl, HCO3
Protein electrophoresis: Protidemia, albuminemia
Renal osteodystrophy: PTH, calcium, phosphorus, alkaline phosphatase

Imagery
Ultrasonography of kidney and bladder: hydronephrosis, Cyst
Enlarged kidneys suggest CKD that is due to diabetes, HIV-associated nephropathy, or infiltrative diseases (eg, amyloidosis)
Small kidneys, Especially with a shrunken cortex, suggest chronic glomerular diseases or interstitial disease
If the size of the two kidneys differs Substantially, stenosis of the renal artery of the small kidney; eps in HTN

Renal biopsy

Recommended but not indicated to unexplained CKD / rapidly progressive glomerulonephritis

Contraindication

Autosomal dominant polycystic kidney disease

Chronic tubular-interstitial nephropathy

Chronic vascular nephropathy

Pathophysiology: The biologic basis for disease in adults