Chronic Kidney Disease and Chronic Renal Failure Flashcards
Why is CKD common, increasing and here to stay?
- Demand for services often outstrips supply
- CKD receives too little attention
- Epidemiology focuses on ESRF not CKD
Clinical non-modifiable risk factors for CKD?
- diabetes
- hypertension
- autoimmune diseases
- neoplasm
- low birth weight
- urinary stones
- lower urinary tract obstruction
- reduction in kidney mass
Infectious risk factors for CKD?
- systemic infections
- urinary tract infections
Exposure to which drugs are a risk factor for CKD?
- Radiographic contrast
- Selected antimicrobial agents
e.g. aminoglycosides and amphotericin B - Nonsteroidal anti-inflammatory agents
e.g. cyclo-oxygenase type 2 inhibitors, cyclosporine and tacrolimus
Sociodemographic risk factors for CKD?
- old age
- ethnic status - African, American, Indian, Hispanic, Asian or pacific Islander
- low income/education
Criteria for CKD?
- Kidney damage for ≥ 3 months
- markers of kidney damage - one or more
- reduced GFR
What are the markers of kidney damage?
- Albuminuria – Allbumin excretion Rate >30mg/24hrs
- Albumin : Creatinine ratio (ACR) >30mg/dl (>3mg/mmol)
- Urine sediment abnormalities
- Electrolyte and other abnormalities due to tubular disorders
- Abnormalities on histology
- Structural kidney abnormalities
- History of kidney transplantation
What is the reduced GFR?
eGFR <60 mls/min
How many stages of CKD are there?
5
Describe CKD stage 1?
- Description
kidney damage with normal or increased GFR - GFR >90
- Features
albuminuria, proteinuria, hematuria - Frequency of features
12 monthly
Describe CKD stage 2?
- description
kidney damage with mild decreased GFR - GFR = 60 to 89
- features
albuminuria, proteinuria, hematuria - frequency of features
12 monthly
Describe stage 3 CKD?
- description
moderate decreased GFR - GFR = 30 - 59
- features
early and chronic renal insufficiency - frequency in features
6 monthly (12 monthly if stable)
Describe stage 4 CKD?
- description
severe decreased GFR - GFR = 15 - 29
- features
late and chronic insufficiency, pre-ESRD - frequency of features
3 monthly (6 monthly if stable)
Describe stage 5 of CKD?
- description - kidney failure
- GFR = <15 (or dialysis)
- features
renal failure, uremia, ESRD - frequency of features - 3 monthly
What are the grading categories for albuminuria?
A1, A2, A3
A1 category grading of albuminuria?
- albumin excretion rate
- <30mg/24hrs - albumin to creatinine ratio
- <3mg/mmol or 30mg/g
A2 category grading of albuminuria?
- albumin excretion rate
- 30 - 300 mg/24hrs - albumin to creatinine ratio
- 3-30 mg/mmol or 30-300 mg/g
A3 category grading of albuminuria?
- albumin excretion rate
- >300 mg/24hrs - albumin to creatinine ratio
- >30mg/mmol or >300mg/g
MDRD equation for eGFR?
eGFR = [186.3 × (creatinine in mg/dl) –1.154 × (age in years)−0.203 x (0.742 if female) × (1.21 if black)]
Cockroft and Gault equation for eGFR?
(140-age) x weight in kg/Creatinine (mg/dl) x 72
Note: Multiply by 0.85 if female
Describe the presentation of CKD?
- Often asymptomatic until advanced
- Can have general body weakness, anemia, loss of appetite, changes in taste, vomiting without any precipitating factors, pins and needles (neuropathy)
- Discovered as a complication of existing illness
- Discovered incidentally as a result of tests and further evaluation required
- Late presentation common
Important history findings in CKD?
- fatigue, anorexia, nausea, vomiting
- breathlessness, haemoptysis
- ankle swelling
- dysuria, haematuria, oliguria
Past medical history to note in CKD?
- previous renal history
- enuresis
- UTIs
- family history
Examination findings in CKD?
- crackles
- vomiting
- tachypnea
- pulmonary edema
- acidosis - pericardial rub
- oedema
- rectal examination
Investigations in identifying renal disease?
- Urine dipsticks
- Lab measures of protein
- Blood tests
- USS
- Renal biopsy
- Nephrologists
Characteristics of urine that point to a UTI?
- pH
- sediment
- smell
What characteristic feature of urine points to heavy proteinuria?
frothy
What characteristic feature of urine points to diabetes?
sweet taste
What can a change in colour of urine represent?
- Blood
- jaundice
- chyluria
- haemoglobin
- myoglobin
- rifampicin
What features of urine determine the concentration?
- volume
- colour
What can you find in urine microscopically?
- Casts
- Cells
- Organisms
- Crystals
- Schisto
What are the urinary casts with clinical significance?
- hyaline
- granular
- waxy
- fatty
- erythrocyte
- hemoglobin
- leukocyte
- epithelial
- myoglobin
Hyaline cast main clinical associtions?
- normal subject
- renal disease
Granular cast main clinical associations?
renal disease
Waxy cast main clinical associations?
- renal insufficiency
- rapidly progressive glomerulonephritis
Fatty cast main clinical associations?
- marked proteinuria
- nephrotic syndrome
Erythrocyte cast main clinical associations?
- glomerular bleeding
- proliferative/necrotizing glomerulonephritis
Hemoglobin cast main clinical associations?
- glomerular bleeding
- proliferative/necrotizing glomerulonephritis
- hemoglobinuria
Leukocyte cast main clinical associations?
- acute pyelonephritis
- acute interstitial nephritis
- proliferative glomerulonephritis
Epithelial cast main clinical associations?
- acute tubular necrosis
- acute interstitial nephritis
- glomerulonephritis
Myoglobin cast main clinical associations?
rhabdomyolysis
What other investigations can you do besides urine microscopy?
- USS
- IVU
- plain X-rays
- renal biopsy
Managing CKD in a well resourced environment?
- Identify CKD (early)
- Identify cause
- Treat underlying cause (reversible)
- Delay progression
- Treat complications
- Involve MDT
- Prepare for RRT
- Dialysis or transplant
Managing CKD in a poorly resourced environment?
- Identify CKD (late)
- Cause often unclear
- No specific therapy
- Delay progression
- Treat complications
- Little expertise
- Often unavailable
- The domain of the wealthy
Non-modifiable mechanisms of renal disease progression?
- race/ethnicity
- gender
Modifiable mechanisms of renal disease progression?
- cigarette smoking
- ↑ protein intake
- ↑ NaCl intake
- Proteinuria
- Angiotensin II
- Hyperglycemia
- Hyperlipidemia
- ↑ plasma Homocysteine
- NSAIDS
- Excess aldosterone
- K depletion
- ↑ procoagulants
Clinical conditions that are mechanisms of renal disease progression?
- hypertension
- anemia
- insulin resistance
How can you delay progression of renal disease?
- BP ≤ 125/75 esp. if proteinuria
- Proteinuria ≤ 0.3 g/24h
- HbA1C ≤ 7
- Protein intake 0.8 - 1 g/Kg
- Dietary sodium ≤ 2g/24h
- LDL ≤ 120 mg/dl (?)
- Stop smoking
- Avoid NSAIDS/nephrotoxins
- Exercise/weight loss/ low alcohol intake
- Correct anemia (? Optimal Hb)
- Control Homocysteine
- Avoid hypokalemia
- Control phosphate
- Low dose aspirin
What are the treatments of chronic renal failure?
- haemodialysis
- peritoneal dialysis
- renal transplant
Describe the haemodialysis setup?
What are the pros and cons of haemodialysis?
pros
1. no immunosuppression
2. suitable for all patient sizes
cons
1. risks of cardiac disease
2. high cost
3. inconvnience - 3-4h/week
4. other complications of CRF
5. fluid restriction
6. need for vascular access
Describe the peritoneal dialysis setup?
Pros and cons of peritoneal dialysis?
pros
1. cheaper than haemodialysis
2. no immunosuppression
con
1. risk of cardiovascular disease
2. inconvenience - though at home
3. fluid restriction
4. not suitable for large patients
Describe the renal transplant procedure?
Pros and cons of renal transplant?
pros
1. increased well being
2. less complications of CRF
3. long-term mortality benefit
4. pregnancy possible
5. cheaper
cons
1. risks of cardiovascular disease
2. 5-10% annual graft failure rate
3. immunosuppression with risks of infection + malignancy
4. organ scarcity
Functions of the kidneys?
- salt and water homeostasis
- BP control
- removal of uremic toxins
- calcium/phosphate balance
- erythropoietin production
- potassium balance
- acid-base balance
Effect of kidney failure on salt and water homeostasis? Treatment?
effect
1. Fluid overload
- peripheral oedema
- pulmonary oedema
2. Fluid depletion
treatment
1. diuretics
2. dialysis
Effect of kidney failure on BP control?
Treatment?
effect
hypertension
treatment
1. anti-hypertensives
2. dialysis
Effect of kidney failure on removal of uremic toxins?
Uremia
1. encephalopathy
2. pericarditis
3. nausea
4. vomiting
5. hiccup
6. bleeding tendency
7. neuropathy
Treatment of failure of removal of uremic toxins?
- dialysis
- ddAVP
Effect of kidney failure on calcium/phosphate balance function of the kidneys?
- Hyperphosphatemia
- Hypocalcaemia
- Renal bone disease
- Tertiary hyperparathyroidism
Treatment of failure to balance calcium and phosphate due to kidney failure?
- Reduced PO4 diet
- PO4 binders
- 1-α hydroxyvitamin D
- parathyroidectomy
Effect of kidney failure on erythropoietin production? Treatment?
effect - anemia
treatment - EPO
Effect of kidney failure on potassium balance?
effect - hyperkalemia
treatment - Potassium diet restriction
dialysis
Effect of kidney failure on acid base balance?
effect - metabolic acidosis
treatment - sodium bicarbonate dialysis
Patient factors that will cause long term issues?
- Distance and money
- Understanding need for F/U
- Low priority cf HIV, TB etc
- Asymptomatic disease
- Intervention may not result in obvious benefit
Non-patient factors that are long term issues?
- Availability of drugs
- Cost of drugs
- Importance of drugs cf HIV, TB, malaria
- Access to bloods for monitoring/screening
- Clear documentation
- Difficult to address all aspects of renal disease