chronic kidney disease

Question 1

what is the definition of CKD?

Answer 1

the presence of kidney damage, manifested by abnormal albumin excretion or decreased kidney function, quantified by measured or estimated GFR that persists for more than three months.

OR in short

Abnormal kidney structure or function, present for >3 months, with implications for health.

Question 2

what are the causes of CKD?

Answer 2

• Diabetes
• Hypertension
• Glomerulonephritis
• Renovascular Disease
• Polycystic Kidney disease
• Obstructive nephropathy – urological problems
• Chronic/recurrent Pyelonephritis
• Others

Question 3

what are the complications of CKD?

Answer 3

• Anaemia of Chronic Kidney Disease
• Chronic Kidney Disease – Mineral & Bone Disease
• Secondary & Tertiary Hyperparathyroidism
• Hypertension
• Cardiovascular Disease
• Malnutrition/sarcopenia
• Dyslipidaemia

And, as CKD progresses

• Electrolyte disturbances
• Fluid overload
• Metabolic acidosis
• Uraemic pericarditis
• Uraemic encephalopathy

Question 4

how is CKD stage categorised?

Answer 4

can be done based on

• GFR
• the presence of albuminuria as a marker of kidney damage
• the cause of kidney disease

Question 5

how does GFR correlate to stage of CKD?

Answer 5

Stage 1 = GFR>90 (only CKD if other evidence of kidney damage)

Stage 2 = GFR 60-89 (same as above)

stage 3a = GFR 45-59 (mild-moderate)

stage 3b = GFR 30-44 (moderate=severe)

stage 4 = 15-29 (severe)

stage 5 = <15 (kidney failure)

Question 6

what would the MDT consist of in CKD management?

Answer 6

• Renal Physicians
• General Practitioners
• Renal Specialist nurses/ Home Care team
• Dieticians
• Pharmacists
• Vascular/Transplant Surgeons

Question 7

how is a CKD patient managed as an outpatient?

Answer 7

• treat underlying disease e.g diabetes, hypertension
• treat infections promptly
• if they have autosomal dominant polycystic kidney disease, tolvaptan can be given
• immunosuppression for GN if appropriate
• reduce CV risk e.g statin, control bp and DM, and lifestyle changes
• reduce CKD progression e.g reduce proteinuria with ACEi/ARB, monitor bloods and control BP
• prevent/ treat complications of CKD e.g dietary advice for low phosphate/K diet. IV iron/folate/vit b12, EPO, vit D supplements, phosphate binders and dietician input.

Question 8

how can you plan for the future with a patient with CKD?

Answer 8

• Start discussions of what options they have if they
  reach ESRF
• Home care team input
• Discuss disadvantages & advantages of types of
  RRT e.g

1) home therapies – APD, CAPD, Home HD
2) Unit-based therapies – Nocturnal HD, conventional HD
3) Active conservative management
3) Transplant

• Refer for fistula (venous mapping)
• Refer for PD tube insertion
• Work-up for transplant (Further tests and refer to Transplant work-up clinic)

Question 9

how can diabetic neuropathy result in CKD?

Answer 9

Type 1 DM or long standing Type 2. Most diabetic patients will undergo screening for diabetic nephropathy and will have

• Raised Urine Albumin: Creatinine Ratio/PCR
• Evidence of long-standing/poorly controlled DM
• Evidence of other microvascular disease e.g retinopathy or peripheral neuropathy

Question 10

how is diabetic nephropathy treated?

Answer 10

• ACEi/ARB to reduce proteinuria
• Anti-hypertensives for BP control
• Cardiovascular risk modification
• Continue other screens for microvascular complications – eye checks and foot checks

Question 11

how does hypertensive nephropathy come about?

Answer 11

Chronic raised BP causing nephrosclerosis.

Often difficult to tell if advanced renal disease at presentation whether HTN caused the renal impairment or renal impairment caused secondary HTN

Question 12

what investigations can be done to identify primary or secondary HTN and how is it treated?

Answer 12

• 24 hour Urinary metanephrines (Phaeochromocytoma)
• Aldosterone: Renin ratio (high in Primary aldosteronism aka Conn’s syndrome)
• Cortisol & Dexamethasone suppression test
  (Cushing’s syndrome)
• TSH (hyperthyroidism)
• MRA (Renal artery stenosis)

treat with antihypertensives

Question 13

how is polycystic kidney disease diagnosed and treated?

Answer 13

Diagnosis

• FH
• USS

Treatment

• Control BP
• As per CKD management
• Tolvaptan (Vasopression receptor-2 antagonist) is
  available for some patients to slow progression of
  CKD.
• Genetic counselling and testing

Question 14

what are the symptoms of Polycystic kidney disease?

Answer 14

Symptoms can be related to the size of the kidney, infection of the cysts (flank pain, haematuria, and fever) or can be asymptomatic

Question 15

what genetic mutations are present in polycystic kidney disease?

Answer 15

Type 1 (85%; PKD1 mutation on Chromosome 16)

Type 2 (15%; PKD2 mutation on Chromosome 4)

Question 16

how do you get anaemia of CKD?

Answer 16

• Decreased production of erythropoietin from the kidney
• Absolute iron deficiency (poor absorption and malnutrition)
• Functional iron deficiency (inflammation, infection)
• Blood loss
• Shortened Red Blood Cell survival
• Bone marrow suppression from uraemia
• Medication induced
• Deficiency of Vit B12 and folate

Question 17

how is anaemia of CKD managed?

Answer 17

1) Measure haematinics – Vitamin B12, Folate, Ferritin, Iron, Transferrin Saturation, CHr

2) If deficient in any of above – replace this first
(IV Iron may be better tolerated than PO)

3) Discuss with renal team regarding starting ESA Aim for Hb 100 - 120

Question 18

how can CKD mineral bone disease be diagnosed?

Answer 18

if a patient with CKD has evidence of one or more of:

1) Abnormalities of calcium, phosphate, alkaline phosphatase, PTH or vitamin D metabolism
2) Vascular and/or soft tissue calcification
3) Abnormalities in bone turnover, metabolism, volume, linear growth or strength

Question 19

what are some low and high bone turnover states?

Answer 19

Low turnover states

• Adynamic bone disease
• Osteomalacia

High turnover states
- Osteitis Fibrosa

Question 20

how can CKD affect levels of

• fibroblast growth factor 23
• alkaline phosphatase
• PTH
• phosphate
• serum calcium
• 1,25 vit d

Answer 20

• Increased Fibroblast Growth Factor-23
• Increased Alkaline Phosphatase and PTH
• Increase Phosphate
• Decreased Serum Calcium
• Decreased 1,25 – Vitamin D as there is reduced hydroxylation of vit D

Question 21

what is territory hyperparathyroidism?

Answer 21

Occurs when PTH release continues despite raised serum Calcium levels (independently)

• As a result of parathyroid gland nodular hyperplasia
• Consequence of advanced CKD

results in mineral bone disease

Question 22

what is the relation between PTH and calcium?

Answer 22

PTH released from parathyroid causes Ca release from bones. Ca increase in blood goes to parathyroid and reduces PTH release.

PTH also aids calcium reabsorption for the kidneys and the intestines

Question 23

how is CKD mineral bone disease managed?

Answer 23

Focus is to reduce:

(1) The occurrence and/or severity of renal bone disease
(2) Cardiovascular morbidity and mortality caused by elevated serum levels of PTH and high phosphate levels and calcium overload.

Question 24

On examination, what will be observed in CKD?

Answer 24

• peripheral oedema
• signs of peripheral vascular disease/ neuropathy
• yellow tinge (uraemia)
• xanthelasma
• signs of anaemia
• periorbital oedema in nephrotic syndrome
• stigma of endocarditis
• pulmonary effusion or oedema
• PD catheter or scars from previous catheter

Question 25

how is CKD monitored?

Answer 25

GFR and albuminuria should be monitored at least annually, according to risk. If high risk, monitor every 6 months, if very high risk, monitor at least every 3–4 months

Question 26

what is the target HbA1c for a CKD patient?

Answer 26

Target Hba1c of ~53mmol/mol (7.0%) unless risk of hypo-glycaemia, comorbidity or limited life expectancy.

Question 27

how can acidosis in CKD be treated?

Answer 27

Consider sodium bicarbonate supplements for patients with eGFR <30 and low serum bicarbonate (<20mmol/L).

Caution in patients with hypertension and fluid overload due to sodium component.

Question 28

how can oedema in CKD be treated?

Answer 28

Restrict fluid and sodium intake. High doses of loop diuretics may be needed.

Combination of a loop and thiazide diuretic can have a powerful effect