Renal disease biochemistry Flashcards
Why creatinine?
Serum concentrations and 24 hour urine output stable
No absorption and very little secretion
Keto-acidosis
Failure of glucose metabolism -> keto-acidosis - 3-OH butyrate
Leads to increased serum concentrations of potassium and phosphate
Renal impairment leads to potassium and phosphate accumulation - enhances acidosis
What urea:creatinine ratio is associated with dehydration
Greater than 100
Acute Kidney Injury serum creatinine and urine output levels
Creatinine serum rise of 26umol/L within 48 hours
Fall in urine output to less than 0.5mL/kg/hr for more than 6 hours
Causes of AKI
Poor perfusion Sepsis Toxins Obstruction (calculus, prostate) Parenchymal (glomerulonephritis)
Causes of CKD
Hypertension Diabetes Hyperlipidaemia Recurrent renal infections Chronic glomerulonephritis Systemic disease Genetic Chronic obstruction Drugs
Lab findings in acute renal injury
Plasma lactate
Infections
Autoimmune
Lab findings of CKD
Serum and urine light chains - myeloma
Glycated Hb
Antibody tests
Biopsy
Use of pre and post dialysis samples
Show effectiveness of dialysis
Determine need for other interventions - diet/supplements/drugs/lipid lowering agents
Monitoring renal transplant patients
ACR or PCR - potential damage to transplanted kidney
Measuring anti-rejection meds (cyclosporin, tacrolimus)
Check for tubular dysfunction
Cockroft and Gault calculation
GFR ml/min
(140-age) x (weight x constant)/serum creatinine
Constant = 1.23 in males, 1.04 in females
Renal tubular disorders
Renal tubular acidosis
Fanconi syndrome
Diabetes insipidus
