Chronic Kidney Disease Flashcards
What is chronic kidney disease?
chronic reduction in kidney function sustained over three months
What causes CKD?
- Diabetes
- HTN
- Medications such as NSAIDs and lithium
- Glomerulonephritis
- PKD
How does CKD present?
- Asymptomatic
- Pallor/Fatigue if anaemic
- Nausea
- Foamy urine(due to protein)
- Oedema
- HTN
- Pruritus
How is CKD investigated?
- EGFR
- Proteinuria: urine albumin:creatinine ratio
- Haematuria with urinalysis or microscopy
- Renal ultrasound
- HbA1c/Lipid profile/BP check
How is CKD classified?
Stage 1: > 90
Stage 2: 60-89
Stage 3a: 45-59
Stage 3b: 30-44
Stage 4: 15-29
Stage 5: <15
What are some complications of CKD?
- Anaemia (less EPO production)
- Renal bone disease (calcium + phosphorus imbalance)
- CVD (IHD)
- Peripheral neuropathy
- Dialysis complications
What risk score can be used to estimate 5 year risk of kidney failure requiring dialysis?
Kidney Failure Risk Equation
What is the referral criteria for CKD to secondary care?
- eGFR less than 30 mL/min/1.73 m2
- Urine ACR more than 70 mg/mmol
- Accelerated progression (a decrease in eGFR of 25% or 15 mL/min/1.73 m2 within 12 months)
- 5-year risk of requiring dialysis over 5%
- Uncontrolled hypertension despite four or more antihypertensives
What is the treatment for CKD?
- Optimise diabetes, BP
- Reduce nephrotoxic drugs
- Treat glomerulonephritis
What are targets for patients with CKD < 80 years old?
BP < 130/80
ACR > 70
What medications are used in CKD?
Slow disease progression: ACE/ARB, SGLT-2 inhibitors (dapaglioflozin)
Atorvastatin 20mg for primary prevention
How are CKD complications managed?
- Oral sodium bicarbonate for metabolic acidosis
- Iron and EPO for anaemia
- Vitamin D, low phosphate and phosphate binders e.g sevelamer for renal bone disease
What is the cause of anaemia in CKD?
- Lower EPO production results in lower RBC production causing normocytic, normochromic anaemia
What is the order of treatment in anaemia in CKD?
- Iron deficiency treated first then use EPO
What are some side effects of EPO?
- HTN
- Bone aches
- Flu like symptoms
- Iron deficiency
- Skin rashes
What is the triad of renal bone disease?
- High serum phosphate
- Low vit D
- Low serum calcium
What is the pathophysiology of renal bone disease?
- Reduced phosphate excretion results in high serum phosphate
- CKD causes less vitamin D activity and so less calcium is reabsorbed from intestines and kidneys leading to PTH glands exreting more PTH (secondary hyperparathyroidism) which stimulates osteoclast activity
- This causes osteomalacia (increased turnover of bones with inadequate calcium) and osteosclerosis (osteoblastis increase their activity to make new bone but this is not mineralised)
How is proteinuria managed?
- ACE/ARB should be used first line for patients with HTN and CKD if ACR > 30
- SGLT2 inhibitors as they block reabsorption of glucose in the proximal tubule which lowers renal glucose threshold
- SGLT2 also reduce sodium reabsorption which reduces intraglomerular pressure
How can you differentiate between CKD and AKI?
Hypocalcaemia is an indication that kidney disease is chronic and not acute (due to low vit d)
What can alter an individuals eGFR?
pregnancy
muscle mass (e.g. amputees, body-builders)
eating red meat 12 hours prior to the sample being taken
What is a potential complication of dialysis?
Dialysis disequilibrium syndrome is a rare but serious complication of haemodialysis
How do you prevent contrast-induced nephropathy?
IV 0.9% fluid pre and post procedure
Most common causative organism of peritonitis secondary to peritoneal dialysis
Staphylococcus epidermidis (Coagulase-negative Staphylococcus)
