Chronic Kidney Disease

Question 1

what is chronic kidney disease?

Answer 1

gradual, irreversible decline in kidney function

Question 2

what is the criteria for chronic kidney disease?

Answer 2

decreased eGFR (<60 ml/min/1.83m2) or markers of kidney damage (albuminuria, electrolyte abnormalities, structural or histological renal abnormalities) present for >3 months

Question 3

what is stage 1 CKD?

Answer 3

eGFR >90 with demonstrable kidney damage (e.g. haematuria or proteinuria)

Question 4

what is stage 2 CKD?

Answer 4

eGFR 60-89 with demonstrable kidney damage (e.g. haematuria, proteinuria, or raised albumin/creatinine ratio)

Question 5

what is stage 3a CKD?

Answer 5

eGFR 45-59

Question 6

what is stage 3b CKD?

Answer 6

eGFR 30-44

Question 7

what is stage 4 CKD?

Answer 7

eGFR 15-30

Question 8

what is stage 5 CKD?

Answer 8

eGFR <15

Question 9

at what stage do patients typically start displaying symptoms?

Answer 9

stage 4 or stage 5 CKD

Question 10

what are the most common causes of CKD?

Answer 10

• diabetic nephropathy
• hypertension
• chronic glomerulonephritis
• chronic pyelonephritis
• polycystic kidney disease

Question 11

what is a high urea indicative of?

Answer 11

‘protein meal’
urea is a majory nitrogenous waste product of protein metabolism within the liver

Question 12

what is the diagnostic test for CKD?

Answer 12

renal biopsy

Question 13

what are the glomerular causes of CKD?

Answer 13

• primary (e.g. IgA nephropathy)
• secondary (e.g. SLE)

Question 14

what are the vascular causes of CKD?

Answer 14

• vasculitis
• renal artery stenosis

Question 15

what are the tubulointerstitial causes of CKD?

Answer 15

• amyloidosis
• myeloma

Question 16

what are the congential causes of CKD?

Answer 16

• polycystic kidney disease
• alport syndrome

Question 17

what are the systemic causes of CKD?

Answer 17

• diabetes
• hypertension

Question 18

what are the developmental causes of CKD?

Answer 18

• vesico-urteric reflux causing chronic pyelonephritis

Question 19

what are the functions of the kidneys?

Answer 19

• waste excretion
• regulation of fluid balance
• acid-base balance
• erythropoietin production
• activation of vitamin D

Question 20

what are the complications of CKD?

Answer 20

CRF HEALS
Cardiovascular disease
Renal osteodystrophy
Fluid (oedema)
Hypertension
Electrolyte disturbance - hyperkalaemia, metabolic acidosis
Anaemia
Leg restlessness
Sensory neuropathy

Question 21

what is the most common cause of death in CKD?

Answer 21

cardiovascular disease

Question 22

what is renal osteodystrophy?

Answer 22

complication of chronic kidney disease that weakens your bones

Question 23

what are the features of renal osteodystrophy?

Answer 23

• reduced bone density (osteoporosis)
• reduced bone mineralisation (osteomalacia)
• secondary/tertiary hyperparathyroidism
• may get spinal osteosclerosis = rugger jersy spine

Question 24

what type of anaemia is seen in CKD?

Answer 24

normocytic, normochromic anaemia

Question 25

what is the first-line management of anaemia in CKD?

Answer 25

erythropoietin injection

Question 26

what does renal ultrasound show in end-stage renal disease?

Answer 26

bilateral shrunken kidneys

Question 27

how does CKD present?

Answer 27

* progressive onset * polyuria * lethargy * pruritus (secondary to uraemia) * anorexia * insomnia * nausea and vomiting * hypertension

Question 28

what drugs are contraindicated in CKD?

Answer 28

* NSAIDs

Question 29

what is microalbuminuria?

Answer 29

raised levels of albumin in urine

Question 30

what causes microalbuminuria in CKD?

Answer 30

diabetic nephropathy

Question 31

how is microalbuminuria screened for?

Answer 31

all patients with diabetes >12 years old should undergo regular urinary albumin:creatinine ratio to screen for microalbuminuria

Question 32

what is the diagnostic criteria for microalbuminuria?

Answer 32

* >2.5 in men * >3.5 in women

Question 33

how do you slow the progression of microalbuminuria?

Answer 33

ACEi (e.g. ramipril)

Question 34

how does CKD disease impact bones?

Answer 34

* low vitamin D (1-alpha hydroxylation normally occurs in the kidneys) * high phosphate * low calcium - due to lack of vitamin D and high phosphate * secondary hyperparathyroidism - due to low calcium, high phosphate and low vitamin D

Question 35

what effect does low calcium and raised phosphate have on the thyroid?

Answer 35

stimulates parathyroid hyperplasia to produce more parathyroid hormone (PTH) to raise calcium levels | secondary hyperparathyroidism

Question 36

what can sustained parathyroid stimulation lead to?

Answer 36

autonomous parathyroid nodule | tertiary hyperparathyroidism

Question 36

what electrolyte disturbances are seen in autonomous parathyroid nodule?

Answer 36

* high PTH * hypercalaemia

Question 37

what is alport's syndrome?

Answer 37

due to a defect in the gene which codes for type IV collagen resulting in an abnormal glomerular-basement membrane (GBM)

Question 38

how is alport's syndrome inherited?

Answer 38

* x-linked dominant pattern * more severe in males

Question 39

what are the features of alport's syndrome?

Answer 39

* normally presents in childhood * microscopic haematuria * progressive renal failure * bilateral sensorineural deafness * lenticonus - protrusion of the lens surface into the anterior chamber * rentinitis pigmentosa * renal biopsy = splitting of lamina densa seen on electron microscopy

Question 40

what is a complications of alport's syndrome?

Answer 40

renal failure in men around 30-40

Question 41

how is alport's syndrome managed?

Answer 41

renal transplant

Question 42

why may a renal transplant fail in alport's syndrome?

Answer 42

failure may be caused by the presence of anti-GBM antibodies leading to a goodpasture's syndrome like picture

Question 43

how is creatinine clearance calculated?

Answer 43

cockcroft-gault formula * age * gender * creatinine * weight

Question 44

what is the morphology of the kidneys in diabetic nephropathy?

Answer 44

* bilateral renal enlargement - due to osmotic diuresis * increased renal blood flow

Question 45

how is hypocalaemia and hyperphosphataemia managed?

Answer 45

* restrict dietary potassium (e.g. dairy products and eggs) * sevelamer * alfacalcidol

Question 46

what is sevelamer?

Answer 46

phosphate binder

Question 47

what is alfacalcidol?

Answer 47

a 1-hydroxylated vitamin D analogue