Chronic Kidney Disease Flashcards Preview

The Renal System > Chronic Kidney Disease > Flashcards

Flashcards in Chronic Kidney Disease Deck (38)
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1
Q

How can chronic kidney disease be defined?

A

Abnormal structure, biochemistry or function of the kidneys for at least 90 days

2
Q

What is eGFR based upon?

A
  1. Serum creatinine levels
  2. Age
  3. Sex
  4. Race
3
Q

How many stages of CKD exist?

A

5

4
Q

What are the stages of CKD?

A
  1. G1
  2. G2
  3. G3 and G3b
  4. G4
  5. G5
5
Q

What is G1 CKD?

A

Normal kidney function

Urine findings, structural abnormalities or genetic trait point to kidney disease

(eGFR > 90ml/min)

6
Q

What is G2 CKD?

A

Mildly reduced kidney function

Urine findings, structural abnormalities or genetic trait point to kidney disease

(eGFR = 60-89ml/min)

7
Q

What is G3 CKD?

A

Moderately reduced kidney function

G3a = eGFR = 45-59ml/min

G3b = eGFR = 30-44ml/min

8
Q

What is G4 CKD?

A

Severely reduced kidney function

(eGFR = 15-29ml/min)

9
Q

What is G5 CKD?

A

Established renal failure

(eGFR < 15ml/min)

10
Q

What is ACR and what is its purpose?

A

Albumin creatinine ratio

Estimates level of protein in urine

(more convenient vs 24 hour collection and compensates for hydration level)

11
Q

What are the different cut offs for ACR?

A
  1. A1 < 3mg/mmol
  2. A2 3-30mg/mmol
  3. A3 > 30mg/mmol

(Nephrotic > 300mg/mmol)

12
Q

Why should a patient with AKI be monitored for many years after?

A

Incidence of developing CKD is higher than normal

(remaining nephrons work harder and burn out sooner as they must take on work of lost nephrons)

13
Q

Why is eGFRcystatinC more accurate than eGFRcreatinine?

A

Creatinine is excreted by both the kidneys and GI tract

CystatinC is excreted only by the kidneys

14
Q

How can accelerated progression of CKD be diagnosed?

A

Sustained decrease in GFR of 25%+ and change in GFR category within 12 months

or

Sustained decrease in GFR of 15ml/min per year

15
Q

Which risk factors exist which can contribute to CKD progression?

A

Other illness

  1. Cardiovascular disease/Hypertension
  2. Proteinuria
  3. Diabetes
  4. Untreated urinary outflow obstruction

Ethnic origin

  1. African
  2. Afro-Carribean
  3. Asian

Lifestyle

  1. Smoking
16
Q

Dysmorphic red cells are often due to what?

A

Glomerular bleeding

17
Q

What are the blood pressure targets in CKD?

A

<140/90mmHg (CKD only)

<130/80mmHg (CKD and diabetes or ACR of >70mg/mmol)

18
Q

The dose of RAAS system antagonists should not be modified in which instances?

A

GFR decrease from pre-treatment is <25%

or

Serum creatinine increase from pre-treatment is <30%

19
Q

In patients with CKD what should be prescribed for either the primary or secondary prevention of CVD?

A

Atorvastatin 20mg

(dosage may be altered in more severe cases)

20
Q

What are the two most common causes of CKD?

A
  1. Hypertension (most common)
  2. Diabetes
21
Q

What is the basic process behind why hypertension causes CKD?

A
  1. Renal artery walls thicken to withstand pressure
  2. Less blood and O2 delivered to glomeruli causing ischaemia
  3. Macrophages enter ischaemic area and release TGF-B plus other growth factors
  4. GFs cause mesangial cell regression to mesangioblasts (secrete extracellular structure matrix)
  5. This causes glomerulosclerosis (scarring and hardening of tissue)
  6. Blood filtering capability is diminished
22
Q

What is the basic process behind why diabetes causes CKD?

A
  1. Excess glucose causes glycation of blood proteins
  2. Efferent arteriole stiffens due to hyaline arteriosclerosis
  3. Glomerular pressure increases leading to hyperfiltration
  4. Mesangial cells secrete more and more extracellular structural matrix
  5. Glomerulosclerosis develops over many years
23
Q

Which vascular conditions can cause CKD?

A
  1. Renal artery stenosis
  2. Nephrosclerosis (hypertensive or ischaemic)
  3. Thrombotic thrombocytopenic purpura (TTP)
  4. Haemolytic-uremic syndrome (HUS)
  5. Small vessel vasculitis
24
Q

What are the clinical signs of CKD?

A
  1. Anaemic (pallor)
  2. Weight loss
  3. Advanced uraemia
    • Lemon yellow, uraemic frost (rare)
    • Encephalopathy (flapping tremor, confusion)
    • Pericardial rub (or haemorrgaic pericardial effusion)
    • Kussmaul breathing (metabolic acidosis)
25
Q

What are the renal consequences of CKD?

A
  1. Local - pain, haemorrhage, infection
  2. Urinary - haematuria, proteinuria, nocturia, oliguria
  3. Impaired salt and water handling (hypertension)
  4. Electrolyte imbalanaces - hyperkalaemia
  5. Acid base disturbance
26
Q

What are the main extra-renal complications of CKD?

A
  1. CVD
  2. Renal osteodystrophy
  3. Anaemia
27
Q

What are the options for end stage renal disease?

A
  1. Haemodialysis
  2. Peritoneal dialysis (can be done at home)
  3. Transplant
  4. Palliative care
28
Q

What is the name of the condition when urea builds up in CKD?

A

Azotaemia

29
Q

What symptoms can azotaemia cause?

A

Usually just nausea, vomiting and loss of appetite

Higher concentrations of urea can lead to:

  1. Pericarditis
  2. Bleeding risk (clotting ability diminishes)
  3. Encephalopathy, asterixis, coma, death
  4. Uraemic frost
30
Q

What is uraemic frost?

A

Develops in severe cases of CKD with azotaemia

Urea crystals precipitate in skin and appear like snow crystals

31
Q

CKD will cause an ________ in potassium and a _________ in calcium

A

CKD will cause an increase in potassium and a decrease in calcium

32
Q

For which reasons does hypocalcaemia occur in CKD?

A

Kidneys become less efficient at activating vitamin D

Activated vitamin D increases gut absorption of calcium

This happens less so hypocalcaemia occurs

33
Q

When hypocalcaemia occurs in CKD, how does the body compensate?

A

PTH secretion increase in reponse to low serum calcium

The bones will lose calcium in order to boost serum calcium levels

This causes weak and brittle bones

This is called renal osteodystrophy

34
Q

How can renal osteodystrophy be treated?

A

Alfacalcidol (active vitamin D)

Phosphate binders

Cinacalcet (calcimimetic)

35
Q

Why does anaemia occur in patients with CKD?

A

The kidneys produce erythropoietin

This induces RBC production in the bone marrow

As kidney production decreases, RBC production will also decrease

36
Q

Decribe how the RAAS is involved in a vicious circle of CKD

A

Decreased fluid filtration in the kidneys will normally induce renin production to raise BP

In CKD, a rise in BP will worsen the CKD as hypertension is the main cause of CKD

37
Q

What is the target Hb level in CKD?

A

100-120g/L

38
Q

How is renal anaemia treated?

A

Oral iron

IV iron (if oral fails)