CKD Flashcards
Causes of CKD [5]
- Diabetic nephropathy (20%)
- GN: usually IgA nephropathy (but also mesangiocapillary GN, SLE or vasculitis)
- Hypertensive nephropathy or renovascular disease
- Pyelonephritis and reflux nephropathy
- Adult polycystic kidney disease
Causes of CKD
Name 2 rare causes
Obstructive uropathy
Chronic interstitial nephritis 2* to MM, amyloidosis
Pathogenesis [4]
- Renal injury causes the kidney to adapt to nephron loss by increasing intraglomeular pressure with glomerular hypertrophy to maintain filtration.
- The glomerulus becomes more permeable to macromolecules such as proinflammatory markers>
- Mesangial cell expansion, fibrosis and glomerular scarring.
- All forms of CKD are also associated with:
- tubulointerstitial disease
- a reduction in blood supply
- lymphocytic and inflammatory mediator infiltration > interstitial fibrosis and tubular atrophy
The CKD syndrome - associated conditions [5]
Anaemia Renal osteodystrophy Cardiovascular risk Hyperlipidemia Malnutrition
Explain why anaemia occurs in CKD
Explain why renal osteodystrophy occurs [4]
Anaemia: decreased erythropoietin production by kidney interstitial fibroblasts [1] leads to lack of RBC growth and differentiation in bone marrow [1]
Renal osteodystrophy:
- kidney is the primary site of phosphate excretion and 1-alpha-hydroxylation of vitamin D
- Reduced levels of 1,25 dihydroxyvitamin D occurs due to renal scarring and reduced phosphate excretion leads to hyperphosphatemia.
- This causes hypocalcaemia which parathyroid gland responds to by producing secondary hyperparathyroidism.
- This promotes calcium resorption causing changes to bony architecture (pre-dialysis have a high turnover and post-dialysis have a low turnover)
Explain why hyperlipidemia occurs in CKD [2]
Explain why cardiovascular risk increases in CKD [5]
Hyperlipidaemia: reduced lipoprotein lipase and hepatic triglyceride lipase [1] means less uptake of lipids by the liver and more in circulation [1]
Cardiovascular risk: due to hypertension, hyperlipidaemia, hyperphosphatemia, calcium-ion phosphate product and PTH
Explain why malnutrition occurs in CKD
altered metabolism of protein, water, salt and potassium
How does CKD usually present? [4]
- Asymptomatic until CKD Stage 4, 5
- Uraemia: anorexia, vomiting, restless legs, fatigue, weakness, pruritus, bone pain
- Impotence
- Amenorrhea
What signs will CKD show in the: Periphery [4] Face [4] Neck [2] Abdomen [3]
- Periphery: HTN, AV fistula (thrill, bruit, recently needled?), signs of previous transplant (bruising (steroids), skin malignancy (immunosuppression)
- Face: pallor (anaemia), yellow tinge (uraemia), gum hypertrophy (ciclosporin), cushingoid appearance (steroids)
- Neck: tunnel line (current or previous small scar over IJV and larger scar in breast pocket area from exit site), parathyroidectomy scar
- Abdomen: PD scar (small midline scar just below umbilicus and small round exit site scar to side of midline), previous transplant (hockey stick scar, ballotable mass), ballotable polycystic kidneys
Investigations
Bloods [5]
Urine [3]
Imaging [3]
Bloods
- FBC normochromic, normocytic anaemia
- U&E, Cr low
- Glucose DM
- Bone profile: hypocalcemia, hyperphosphatemia, elevated PTH
- Elevated ALP in osteodystrophy
Urine
- Urinalysis proteinuria, hematuria
- C&S exclude recurrent UTI
- Urine albumin: Cr ratio
Imaging
- Renal ultrasound showing bilateral enlargement in APKD, DM, MM
- MAG3 renogram showing asymmetrical kidney size
Renal biopsy
Renal biopsy
What will you see if its rapidly progressive disease? [2]
Complications
Rapidly progressive disease will show normal sized kidneys with unclear cause
Complications: bleeding, pain
What are 3 modalities of management
- Identify and treat reversible causes
- Limit and prevent complications
- Symptom control
- RRT
What are the 4 components to limitation of CKD complication
Limit and prevent complications:
- BP
- Renal bone disease
- CVD risk
- Diet
Symptom control in CKD mx
Anaemia [4]
Anaemia
- monitor RBC, replace Fe, folate, B12
- Dardepoetin if anaemia is unresponsive
- Haem referral if suspect red cell aplasia due to anti-EPO ab
When would you suspect red cell aplasia in CKD patient? [3]
Side effects of dardepoeitin [4]
if Hb continues to fall and no infection, haemolysis or blood loss
SE (dardepoietin):
- Accelerated HTN > encephalopathy, seizures
- Bone aches
- Flu-like sx, rash, urticaria
- Increased risk of thrombosis
