4. Chronic kidney disease: drug therapy Flashcards Preview

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Flashcards in 4. Chronic kidney disease: drug therapy Deck (9)
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1
Q

What is the definition of CKD?

A

Impaired renal function for >3months based on abnormal structure or function (GFR < 60ml/min)

2
Q

What is the classification of CKD?

A
  • CKD is classified into 5 stages based on the GFR and presence of renal damage (proteinuria, hematuria, sediment, abnormal anatomy or evidence of a systemic disease)
  • Symptoms usually only occure by stage 4 (GFR < 30ml/min)
  • End-stage renal disease (ESRD) is defined as GFR < 15ml/min or need of renal replacement therapy (RRT)
3
Q

What are the causes of CKD? Rare causes? Inherited diseases?

A
  • Diabetes mellitus
  • Glomerulonephritis
    • Commonly IgA nephropathy
    • Systemic disorders (SLE, vasculites)
  • HTN or renovascular disease
  • Pyelonephritis and reflux nephropathy
  • Unknown (at the time of patient arrival biopsyis no longer diagnostic)

Rare causes:

  • Obstructive uropathy: commonly causes AKI (often reversible)
  • Chronic interstitial nephritis (myeloma, amyloidosis)
  • Following previous AKI

Inherited diseases:

  • Adult PKD (most common inherited cause)
  • Alport’s syndrome and Fabry’s diseases are rare
4
Q

What is the management of CKD?

A

Refer early to a nephrologist if any of the criteria:

  • Stage 4-5 CKD
  • Moderate proteinuria (ACR > 70mg/mmol) unless due to DM and already appropriately treated
  • Proteinuria + hematuria
  • Rapidly falling eGFR (>5ml/min within a year or >10ml/min within 5 years)
  • Poorly controlled BP despite ≥ 4 antihypertensive drugs at therapeutic doses
  • Known or suspected rare genetic causes of CKD
  • Suspect renal artery stenosis
5
Q

What is the aim of management of CKD?

A

Limiting the progression of the disease, minimizing the risk for complications and handling these complications when they arise.

6
Q

How can we identify and treat the reversible causes?

A
  • Relieve obstruction
  • Stop nephrotoxicity drugs
  • Deal with hypercalcemia
  • Deal with cardiovascular risks (stop smoking, healthy weight)
  • Tight glucose control in DM
7
Q

How do we limit the progression/complications of CKD?

A

Blood pressure:

  • Even a small BP drop may save significant renal function
  • The target BP is < 140/90 (<130/90 if significant proteinuria)
  • In diabetic kidney disease, it is recommended to treat with ACEI or ARB even if the BP is normal

Diabetes mellitus:

  • Maintain HbA1C <7%, fasting glucose < 6 mM and post-prandial glucose <7.5 mM

Renal bone disease:

  • CKD patients are at risk of developing osteodystophy
    • PTH level is monitored and treated if raised as well as phosphate elevation (rises in CKD and causes PTH to increase further and precipitate in vessels)
      • Achievable through diet and phosphate-binders that decrease GI absorption
      • Vitamin D analogues and Ca2+ supplements can delay bone disease and hyperparathyroidism

Cardiovascular disease:

  • In stages 1-2, there is a higher risk of CV death that reaching ESRD
    • Statins and low-dose aspirin are used to manage the risk

Diet:

  • All patients should be reviewed by a dietetician for advice on healthy, moderate protein diet, K+ restriction (if hyperkalemic) and avoid high phosphate foods (milk, eggs, cheese)
8
Q

How do we control symptoms?

A

Anemia:

  • Blood count should be performed routinely
  • Iron/B12/folate should be supplemented if necessary
    • If still anemia –> recombinant human EPO

Acidosis:

  • NaHCO3 supplements for patients with low serum bicarbonate
    • This only improves symptoms but may slow progression
    • Caution in patients with HTN as sodium load can increase BP

Edema:

  • High doses of loop diuretics may be needed (furosemide, metolazone)
  • Restriction of fluid and sodium intake

Restless leg syndrome:

  • Low ferritin may worsen symptoms
  • Clonazepam and gabapentin may help
  • Quinine sulfate can help with cramps
9
Q

What is the last possible treatment for ESRD?

A

Renal replacement therapy