Chronic kidney disease

Question 1

Define CKD

Answer 1

DEFINITION: progressive loss of kidney function over a period of months or years

The definition is based on the presence of kidney damage or decreased kidney function (i.e. eGFR < 60 ml/min per 1.73 m2) for three months or more .

BMJ; Proteinuria or haematuria, and/or a reduction in the glomerular filtration rate, for more than 3 months’ duration.

Question 2

Classify CKD by stages

Answer 2

○ Stage 1: Normal
• eGFR > 90 ml/min per 1.73 m2 with other evidence of CKD (microalbuminuria, proteinuria, haematuria, structural abnormalities, biopsy showing glomerulonephritis)

○ Stage 2: Mild Impairment
• eGFR 60-89 ml/min per 1.73 m2 with other evidence of CKD

○ Stage 3a: Moderate Impairment
• eGFR 45-59 ml/min per 1.73 m2

○ Stage 3b: Moderate Impairment
• eGFR 30-44 ml/min per 1.73 m2

○ Stage 4: Severe Impairment
• eGFR 15-29 ml/min per 1.73 m2

○ Stage 5: Established Renal Failure
• eGFR < 15 ml/min per 1.73 m2 or on Dialysis

Note; it can be classified by eGFR or by ACR (albumin creatinine ratio) -> above 3 is moderate. above 30 is severe

Question 3

Explain the aetiology/risk factors of CKD

Answer 3

• In developed countries it is mainly associated with:
○ Age
○ Diabetes mellitus
○ Hypertension
○ Obesity
○ Cardiovascular disease

• Other risk factors:
○ Arteriopathic renal disease
○ Nephropathies
○ Family history
○ Neoplasia
○ Myeloma
○ Systemic disease (e.g. SLE)
○ Smoking
○ Chronic use of NSAIDs

Question 4

Summarise the epidemiology of CKD

Answer 4

• COMMON
• Risk increases with age
• Often associated with other diseases (e.g. cardiovascular disease)

Question 5

What are the causes of oedema in CKD?

Answer 5

Oedema is caused by reduction in GFR

Peripheral oedema is caused by reduction in serum albumin due to protein uria

Question 6

What are the most common causes of CKD?

Answer 6

The most common causes are diabetes mellitus and hypertension.

Question 7

What are the presenting symptoms of CKD?

Answer 7

The majority of people are asymptomatic, and the diagnosis is determined only by laboratory studies.

-> Presence of risk factors
-> Weakness and Fatigue
Headaches
Oedema
Oliguria
Incresed serum BUN:Creatinine ratio
Mild anaemia

Additional symptoms suggesting progression;

-> Anorexia (not eating)
-> Nausea with or without vomiting
- Pruritus
○ Peripheral oedema
○ Muscle cramps
○ Pulmonary oedema
• Sexual dysfunction is common

Question 8

Recognise the signs of CKD on physical examination

Answer 8

• Physical examination rarely reveals many clues
• May show signs of underlying disease (e.g. SLE)
• May show complications of CKD (e.g. anaemia)

• Signs of CKD:
○ Skin pigmentation
○ Excoriation marks
○ Pallor
○ Hypertension
○ Peripheral oedema
○ Peripheral vascular disease

Question 9

Investigations for CKD?

Answer 9

Serum creatinine - elevated
Urinalysis - haematuria and or proteinuria
Urine microalbumin - microalbuminuria
Renal ultrasound - renal calculi
eGFR estiomate - < 60ml/min

Renal biopsy - glomerulonephritis
Serology ;
- ANA - SLE
• c-ANCA - granulomatosis with polyangiitis (Wegener's)
• Anti-GBM - Goodpasture's syndrome
Hepatitis and HIV serology

Got most of above from BMJ best practice - really good as it tells you expected outcome of result too (use for other conditions)

Question 10

What are the principals of managing CKD?

Answer 10

Stage 1-4 no uraemia/anaemia;

• ACE inhibitor eg lisinopril OR ARB
• Statin
• 2nd line is CCB

Stage 5

• RRT eg Dialysis
• transplant

add furosemide if they develop fluid overload later

Question 11

What is cystatin C and its use in CKD diagnosis?

Answer 11

Cystatin C is an alternative biomarker of renal function; due to muscle mass, it displays less variation than creatinine and offers greater accuracy of GFR estimation, which improves the relationship between eGFR and subsequent risk of CKD-related outcomes, such as cardiovascular death and end-stage renal failure.

You would prefer to use it over creatinine in;
stage 3a+ disease so egfr 59 and below

Question 12

when do we consider referal to renal team in a pt with a reduced egfr?

Question 13

complications of CKD?

Answer 13

Electrolyte disturbance;
acidosis
hypokalamia
hyperphosphataemia -> cramps
hypocalcaemia -> tetany, parasthesias

Bone profile:
2nd Hyper PTH
osteomalacia

Anaemia

Uraemia -> causes pericarditis and encephalitis

Fluid overload

Hypertension - due to innapropriate RAS activation

Question 14

how do we manage uraemia in CKD?

Answer 14

depends on symptoms (not level of uraemia)

often just present with itching

if pericarditis or encephalitis -> dialysis

Question 15

how would we manage hypertension in CKD?

Answer 15

ACEi - eg ramipril

usually need 2 of them

Question 16

see y6 dropbox slides

Answer 16

https://www.dropbox.com/s/qza91tx6972atzw/Y6%20Renal%20History%20taking%20and%20Examination.pptx?dl=0

Question 17

How does haemodialysis work? How often does it need to be done?

Answer 17

blood pumped out of the body via the vein in the AV fistula

blood circulates through the dialysis machine which has semi permeable membrane allowing exchange of toxins with the dialysate solution

this takes 4hours

should be done 3x per week

Question 18

What is a Tesio line and how is it different to a normal central venous line?

Answer 18

A Tesio line is a double lumen central line. One lumen enters the right atrium, the other
sits outside the RA in the vena cava. The line is tunneled under the skin to the lateral
right chest where it exits the skin.

The main difference can be seen clinically at the skin
exit point. With a central line, only 1 line enters the skin, it bifurcates into two lumens
outside the body. With the Tesio, there is no bifurcation, two lumens enter the skin.
When removed, it leaves a scar that looks like a vampire fang bite

two circles next to each other or a straight scar if the two holes merge when pulling it out.

Question 19

3) What is an arteriovenous fistula and how does it work?

Answer 19

AV fistulas are a connection between an artery and a vein. Usually done by a vascular
surgeon in the forearm.

After being formed, they take upwards of six weeks to mature. This process is known as
fistula maturation. The turbulent blood in the fistula also generates the palpable pulsatile thrill
and bruit than can be auscultated. The presence of both thrill and bruit indicates fistula
patency

Question 20

4) How does peritoneal dialysis work? How often does it need to be done?

Answer 20

dialysis solution introduced into the peritoneal cavity and left for some time

this allows natural exchange of toxins into the dialysate

the fluid is then removed

done daily -> 1-4 times depending on type - in sleep or during day.

continuous ambulatory PD (CAPD) - 4x pd
This is different to automated PD - 1x at night

Question 21

5) What are the risks/benefits of each type of dialysis?

Answer 21

Haemodialysis;
Risks; blood infection, thrombosis, done in clinical setting
Note; must make dietary changes

Peritoneal dialysis;
Better tolerated, less expensive, can be done at home
Risks; abdominal infections,
Note; patient has to be able to care for themselves or have family/carers to help. If hx of lots of abdominal surgery, cant have this.

https://www.dropbox.com/s/t825yy3acgupqu3/Y6%20Renal%20Exercises%20-%20Qs%20and%20Answers.docx?dl=0

Question 22

6) What are the risks of a fistula vs a Tesio line

Answer 22

Fistula;
may not mature, may fail, may stenose or lose patency, low risk of
infection, can be damaged, unsightly, takes time to mature 6-8wks

Tesio; needs replacing every few years, risk of line sepsis/infection, easier to
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