Kidney Disease Flashcards
What is chronic kidney disease
Abnormal kidney function and/or structure
Can have normal function (e.g. U&E are fine) but will still have CKD if there is a structural problem with the kidney
What does CKD increase your risk of
Acute kidney injury
Falls
Frailty
Mortality - particularly from CVD
What conditions does CKD often co-exist with
cardiovascular disease
diabetes
How do you diagnose CKD
Raised creatinine or reduced GFR after more than 90 days
Need 2 samples at least 90 days apart
What are the stages of CKD
G1 - normal function but structural or urine finding G2 - mild reduction in function G3 - moderate reduction G4 - severe reduction G5- renal failure
What is the significance of albumin in the urine
It is a marker or endothelial or vascular disease
Its a glomerular protein
What does the albumin:creatinine ratio mean
Measure of glomerular damage
The higher the ratio the worse the disease
How would you follow up someone with AKI
Advise that they are at risk of CKD developing
Monitor for at least 2-3 after the AKI episode but should probably do lifetime
list risk factors for CKD
Diabetes Hypertension AKI CVD Structural kidney disease Family History
what is the definition of accelerated CKD progression
Sustained decrease in GFR of 25% or more and a change in GFR category within a year
What can chronic NSAID use do to the kidneys
Can cause AKI
What is the target BP for people with CKD
Systolic below 140mHg
Diastolic below 90mmHg
What is the target BP for people with CKD and diabetes (or ACR of 70 or more)
Systolic below 130mmHg
Diastolic below 80mmHg
How do you manage ACEi or ARB treatment in CKD
DO NOT alter does if the GFR decrease is less than 25%
or if serum creatinine increase is less than 30%
How do you manage statin therapy in CKD
Offer Atorvastatin 20mg for CVD prevention
Increase dose if there isn’t sufficient reduction
List the 3 most common causes of CKD
Diabetes
Hypertension
Glomerulonephritides - primary or secondary
If you find FSGS what must you do
Test for blood borne viruses
List less common causes of CKD
Vascular disease - macro and micro
Tubulointerstitial problems
Calculi
Prostatic and Bladder cancer
List clinical signs of CKD
Anaemia - pallor Weight loss Uraemia: - lemon yellow - uremic frost on skin - twitching - encephalopathic flap - confusion - kussmaul breathing
List symptoms of CKD
nausea and vomiting anorexia weight loss fatigue Itch restless legs and muscle twitches confusion Pain - bone, nerve, visceral etc depression
List renal consequences of CKD
Local pain, haemorrhage, infection
Haematuria or proteinuria
Hypertension
Impaired salt, water electrolyte handling
List extra renal consequences of CKD
CVD
Mineral and bone disease
Anaemia
Nutrition
How do you manage CKD
Renal replacement therapy - dialysis or transplant
Conservative - will die eventually
How can you reduce CV risk
Smoking cessation Weight loss and exercise Limited salt intake Control hypertension Statin
How does CKD lead to bone disease
Changes in minerals - e,g, calcium, phosphate
Increased fracture risk, pain and expansion
What are the consequences of mineral bone disease in CKD
Bone pain fractures CV events Vascular calcification Lower QoL
What dietary changes can help with CKD-MBD
Reduce phosphate, salt, potassium, fluids
What medications can help with CKD-MBD
Phosphate binders
Active Vit D - alfacalcidol
How can you treat renal anaemia
Iron therapy
Try oral first but if it doesn’t work use IV
What 3 concepts are involved in dialysis
Diffusion
Convection
Adsorbtion
What is the function of dialysis
Allows removal of toxins which build up in end stage renal disease (urea, potassium, sodium)
Allows infusion of bicarbonate
How does haemodialysis work
Need good vascular access
Filter through the machine which has lots of microfilaments
Dialysate runs through machine which sets up gradient needed to remove toxins
Also sets up pressure gradient to remove some water
what does adsorption mainly affect
affects the plasma proteins and solutes that are bound to them
They stick to the membrane surface and then removed
How does hemodiafiltration work
mainly by convection
Add a huge volume of ultra-pure filtrate so that the pressure gradient helps remove more
Some diffusion occurs
Which factors affect efficacy of haemodiafiltration
Water flux - rate and vol Membrane pore size Pressure difference across membrane Viscosity of fluid Size, shape and charge of molecules
How much fluid is used in high volume HDF
Replacement volume of more than 20 litres
How often does someone get dialysis
Minimum of 4 hours, 3 times a week
More effective with longer treatment time
What diet restrictions are put on a dialysis patient
Fluid - around 1l per day Low salt diet Low potassium diet Low phosphate diet Affects what you eat and how you cook etc
What is a tunnelled venous catheter
Catheter inserted into a large vein such as IJV
Can stay in for 2-3 weeks
What are the pros of tunnelled venous catheter
Easy to insert
Can be immediately used
What are the cons of tunnelled venous catheter
High risk of infection
Can become blocked
Can cause damage (stenosis/ thrombosis) to central veins making future line insertion difficult
How would you diagnose and treat a catheter infection
Blood cultures
FBC and CRP
Swab exit site
Treat with vancomycin and gentamicin
Line removal or exchange
What pathogen most commonly infects venous catheters
staph aureus
What is the gold standard of dialysis vascular access
Arteriovenous Fistula
Surgically connect artery and vein
List common sites for AV fistula
Radio cephalic
Brachio cephalic
Brachio basilic
What are the pros of AVF
Good blood flow
Less likely to get infected
What are the cons of AVF
Requires surgery
needs 6-12 weeks before use
Can limit the blood flow to distal arms
Can thrombose or stenose
How can grafts be used in dialysis
Can put in a arteriovenous grfat if natural vein isn’t good enough
HeRO graft - connect graft to right atrium
List potential complications of dialysis
Hypotension - dizziness or LoC Haemorrhage Loss of vascular access Arrhythmia Cardiac arrest
How does peritoneal dialysis work
Solute removal by diffusion of solutes across the peritoneal membrane
Also creates an osmotic gradient to remove water
Can be done at home Either several bags a day or one that stays in all day - drained at night
What organisms commonly cause infection in PD
Contamination of site - staph, strep or diptheriods
Gut bacteria translocation - E.coli or klebsiella
How do you treat infection in PD
Culture the PD fluid
Give intraperitoneal antibiotics
may need to remove the catheter
What are some potential complications of PD
Infection - peritonitis
Membrane failure - cant remove enough water/solutes
Hernias
what blood test results suggest dialysis is needed
Resistant hyperkalaemia
eGFR < 7 ml/min
Urea > 40 mmol/L
Unresponsive metabolic acidosis
What symptoms may suggest that dialysis is needed
Nausea Anorexia Vomiting Profound fatigue Itch Unresponsive fluid overload
How do you start HD
Gradually build up
stat at 90-120 mins then increase slowly to 4hrs
What can happen if you start dialysis too fast
Can lead to disequilibrium syndrome
Cerebral oedema and possible confusion, seizures and occasionally death
How do you start up PS
Start with smaller fill volumes and gradually increase
Regular clinic follow ups
Why might you withdraw from dialysis
Haemodynamic instability
Progressive dementia
Inability to remain on therapy for full duration due to agitation
Cardiovascular event
Terminal cancer
Increasing fraility and inability to cope at home
What happens when you withdraw someone from dialysis
Palliative care
List common symptoms of kidney disease
Loin pain Polyuria and nocturia Haematuria - micro or painless macro Proteinuria Hypertension Fluid retention Bone pain Signs of anaemia
Why do people with kidney disease become anaemic
Kidneys are responsible for producing erythropoietin
When they are damaged it affects this and it becomes defective
How does kidney disease lead to bone pain
Vitamin D metabolism and phosphate excretion become abnormal
This leads on to bone pain
What examination finding suggest kidney disease in the asymptomatic patient
dipstix microscopic haematuria &/or proteinuria
reduced estimated GFR on biochemical screen
raised BP
incidental findings on abdominal imaging
List drugs that can affect renal function
ACEi, ARB, diuretics
NSAIDs
Antibiotics
PPI’s
How do NSAIDs affect the kidneys
They decrease glomerulus pressure and decrease GFR
This causes fluid retention
Which antibiotic is nephrotoxic
Gentamycin
Why is retinopathy sometimes seen in kidney disease
It is a sign of DM or hypertension
Both of which can cause kidney disease
What is accelerated hypertension
A medical emergency
Diastolic BP>120mmHg
Seen in young or sick patients
List symptoms of accelerated hypertension
Papilloedema Encephalopathy Fits Cardiac failure Acute renal failure
How might vasculitis present in the skin
Non-blanching rash
Not raised
How can you quantify urinary protein
24hr urine collection
Urine protein/creatinine ratio - can be done on spot test
Describe the different ranges for proteinuria
Low grade - <1g per day
Heavy 1-3g per day
Nephrotic range >3g per day
What does a red cell urinary cast indicate
Pathology - usually nephritic syndrome
What does a leucocyte urinary cast indicate
Infection or inflammation
What does a granular urinary cast indicate
Indicator of chronic disease
What is the ECG sign of hyperkalaemia
Tall tented T waves
What causes nephrotic syndrome
Glomerular disease
What are the symptoms of nephrotic syndrome
Proteinuria >3g per day
Hypoalbuminemia
Hypercholesterolaemia - due to overwork of liver
Oedema - everywhere!!
What are the signs of nephritic syndrome
Oliguria
Oedema
Hypertension
Active urinary sediment
What causes nephritic syndrome
It is the clinical syndrome of glomerulonephritis
What gives better survival - dialysis or transplant
Transplant - all sources are better than dialysis
List the different types of transplant
Deceased heart beating donors - brain dead
Non-beating heart donor - must be done fast
Live donation
List contraindications for kidney transplant
Malignancy Active HCV or HIV infection Untreated TB Severe IHD Active vasculitis Severe peripheral vascular disease Hostile bladder
Patients must have a reasonable life expectancy to be suitable for transplant - true or false
True - must be more than 5 years
How do you match a kidney to a recipient
By blood group
HLA typing - good match gives lower chance of rejection (especially in case of second transplant)
List potential sensitising events for rejection of a transplant
Blood transfusion
Pregnancy or miscarriage
Previous transplant
They will have pre-formed antibodies to non-self antigens
How are kidneys allocated
Paediatrics get the first offer
Then goes to an ideal match
Then a favourable match - e.g. one criteria isn’t perfect
Then any other match
how does paired donation work
2 sets of live donors and recipients
The donors aren’t a match for their loved ones but are compatible with the other pairs recipient
This way both recipients get a kidney and both donors give one - just to the opposite pair
Where is a new transplant placed
New kidney is grafted on to the iliac vessels - lower down
Native kidney does not come out unless causing infection or polycystic
Describe the different levels of graft function
Immediate graft function - good urine output and falling creatine etc immediately
Delayed - get acute tubular necrosis and may need dialysis for a while but starts working in 10-30 days
Primary non function - never works
What are the different types of rejection
Hyperacute - caused by preformed antibodies
Acute rejection - cellular or antibody mediated
Chronic - antibody mediated with slow decline in function
what type of rejection is salvageable
Acute
Can be treated with increased immunosuppression
Describe the immunosuppressive therapy needed in transplant patients
Start with IL-2 antagonist as induction
Prednisolone Iv in op
Then give prednisolone, tacrolimus and MMF as maintenance
List general complications of immunosuppression
Infection - UTI and LRTI
CMV disease BK Nephropathy
Cancer
Post transplant lymphoproliferative disease - EBV
