Chronic renal failure (CRF) is defined as progressive loss of kidney function. As the terminology is very wide ,difficult to define and to label specifically, a new and wider terminology is needed.In 2000, the National Kidney Foundation (NKF) Kidney Disease Outcome Quality Initiative (K/DOQI) Advisory Board approved development of clinical practice guidelines to define Chronic Kidney Disease (CKD) and to classify stages in the progression of chronic kidney disease
Kidney Vs Renal
The word “kidney” is of Middle English origin and is immediately understood by patients, their families, providers, health care professionals, and the lay public of native English speakers.On the other hand, “renal” and “nephrology,” derived from Latin and Greek roots, respectively, commonly require interpretation and explanation.Therefore kidney is chosen in the new terminology instead of renal.The term Acute Renal Failure and “End-Stage Renal Disease” (ESRD) has been retained
DEFINITION OF CHRONIC KIDNEY DISEASE
STAGES OF CHRONIC KIDNEY DISEASE
Glomerular Filtration Rate (GFR)
The flow rate of filtered fluid through the kidneys.
Measurement:
Inulin Clearance
Radio-isotopes
- Crhomium EDTA
- Tc DTPA
- Iohexol
- Mean values of 127 mL/min/1.73 m2 in men and 118 mL/min/1.73 m2 in women
- After the age of 30 years, GFR decreases by approximately 1.0 mL/min/1.73
UrINARY CREATININE CLEARANCE
- Creatinine Clearance:
An approximation of GFR – 24 hour urine calculation of creatinine clearance
The creatinine clearance is usually determined from a 24 hour urine collection
Result must be in ml/min
Creat Cl = Urinary Creat (mmol/l) x Urine Volume(ml)
Time (hr)x Plasma Creat(umol/l)
2 .Limitations with creatinine clearance
- Inadequate urine volume – esp in patient with advanced CKD
- Lab error – result as variation of measured creat
- Increase creat secretion -Some patients with advanced disease have a creatinine clearance that exceeds the GFR by more than two fold.
