Chronic Kidney Disease Flashcards
What is another term for chronic kidney disease?
Chronic kidney failure
What is chronic kidney disease?
It describes a gradual loss of kidney function over a period of more than three months
This reduction in kidney function tends to be permanent and progressive
What is the general function of the kidneys?
They filter waste and excess fluids from the blood, which are then excreted in the urine
What occurs if chronic kidney disease is left untreated?
Patients will eventually develop end stage kidney disease (ESKD), in which dangerous levels of fluid, electrolytes and waste can build up in the body
What are the six risk factors of chronic kidney disease?
Age, with the risk increasing with increasing age
Ethnicity, with individuals of an African-America, Native American or Asian-American having an increased risk
Family History
Drugs, which affect the kidneys
Obesity
Medical Conditions, such as hypertension and diabetes
What is the general cause of chronic kidney disease?
It can be caused by any condition that impairs kidney function, causing kidney damage to worsen over several months or years
What are the six causes of chronic kidney disease?
Diabetes Mellitus
Glomerulonephritis
Hypertension
Polycystic Kidney Disease
Renal Vascular Disease
Recurrent Pyelonephritis
How does chronic kidney disease most commonly present?
Asymptomatic and it is therefore diagnosed with routine testing
What are the three main clinical features of chronic kidney disease?
Oedema, which can be peripheral and pulmonary
Hypertension
Muscle Cramps
What are the three clinical features of advanced stages of chronic kidney disease (stage five)?
Oliguria, which is a decreased urine output < 0.5ml/kg/hr
Chest Pain, which occurs if fluid builds up in the lining of the heart
Shortness of Breath, which occurs if fluid builds up tin the lungs
What four investigations are used to diagnose chronic kidney disease?
Blood tests
Urine dipstick test
Ultrasound scan
Renal biopsy
What four specific blood tests are used to diagnose chronic kidney disease?
eGFR
Serum creatinine
Serum urea
Serum bicarbonate
What is eGFR?
The estimated glomerular filtration rate and is the amount of blood passing through the glomeruli each minute
It therefore measures the kidney’s function in filtering blood
How do we calculate eGFR?
We measure the patient’s serum creatinine levels and apply it in estimating equation
What eGFR estimating equation is most commonly used in clinical practice?
MDRD 4 variable equation
What eGFR indicates a diagnosis of chronic kidney disease?
eGFR < 60ml/min/1.73m^2
What three reasons explain why an eGFR can be inaccurate?
A reduction in GFR by more than 50% is required before a rise in creatinine levels occurs
The GFR estimating equations only report a GFR number if it is less than 60ml/min/1.73m^2
Creatinine is the breakdown product of muscle. It can cause inaccurate eGFR measurements due to the fact that its normal physiological level is dependent upon various factors, such as muscle mass, age, ethnicity, gender, weight, liver disease, etc.
What is a urine dipstick test?
It involves collecting a midstream sample of urine from the patient
A dipstick – a thin, plastic stick with strips of chemicals on it – is then placed in the urine to detect abnormalities.
How does a urine dipstick test generally detect chronic kidney disease?
This investigation is used to assess the kidney’s function in retaining large molecules, such as albumin and haemoglobin, during filtration
What three urine dipstick results indicate a diagnosis of chronic kidney disease?
Haematuria, which is defined as a dipstick positive result of 1+ blood
Proteinuria, which is the presence of more than 1.5g (150mg) of protein within urine per day
Albumin: Creatinine Ratio (ACR), with a result of > 3mg/mmol being significant. This result allows us to identify the quantity of protein that is leaking from the kidneys.
What investigation is required to confirm a diagnosis of CKD?
Urine ACR
When should urinary ACR be conducted? Why?
Morning
The ACR can be affected by factors such as dehydration, certain drugs, and vigorous exercise, which can cause elevated results and give false positives
How do renal ultrasound scans diagnose chronic kidney disease?
It is used to assess the kidney’s structure and size
A diagnosis of chronic kidney disease is indicated by asymmetrical, shrunken kidneys
What is a renal biopsy?
A renal biopsy involves using a special needle to extract small pieces of kidney tissue for light and electron microscopic examination
What are the two classifications of chronic kidney disease?
G score
A score
How do we determine a patient’s G score?
eGFR
What is stage one (G1)?
GFR > 90
What is stage two (G2)?
GFR between 60 and 89
What is stage three a (G3a)?
GFR between 45 and 59
What is stage three b (G3b)?
GFR between 30 and 44
What is stage four (G4)?
GFR between 15 and 29
What is stage five (G5)?
GFR < 15
How do we determine a patient’s A score?
Albumin: creatinine ratio
What is stage A1?
ACR < 3mg/mmol
What is stage A2?
ACR between 3 and 30mg/mmol
What is stage A3?
ACR > 30mg/mmol
What is the diagnostic criteria for chronic kidney disease?
eGFR less than 60, which is a G score greater than 3
Albumin: creatinine ratio > 3mg/mmol, which is an A score greater than 2
Why can the classification of chronic kidney disease indicate?
it indicates the patient’s risk of developing cardiovascular disease and end stage kidney disease
The higher stages of chronic kidney disease, the greater the patient’s risk of developing these complications
When is a chronic kidney disease patient classified as having a complication risk?
They have a G score greater than 3b with any level of proteinuria
What is the aim of chronic kidney disease management?
It aims to slow the progression of the disease and reduce the risk of complications
In what four ways do we manage chronic kidney disease?
Conservative Management
Hypertension Management
Anaemia Management
Renal Bone Disease Management
When is conservative management of chronic kidney disease recommended?
It is the first line management option
How do we conservatively manage chronic kidney disease?
It involves encouraging patients to adapt a lower protein diet
This diet is used to minimise the waste products in blood and therefore it reduces the amount of work the kidneys conducts
How do we manage hypertension in CKD patients?
ACE inhibitors
In what three circumstances do we prescribe hypertensive agents in CKD patients?
A diabetic patient with an ACR > 3mg/mmol
A hypertensive patient with an ACR > 30mg/mmol
All patients with an ACR > 70mg/mmol
What blood pressure do we aim for in CKD patients?
Less than 140/90mmHg
Why does CKD result in anaemia?
In a healthy patient, renal cells are involved in the production of erythropoietin, which is the hormone that stimulates production of RBCs
Chronic kidney disease therefore results in a reduced production of erythropoietin, thus leading to the development of anaemia
How do we treat anaemia in CKD patients?
Erythropoiesis stimulating agents, such as exogenous erythropoietin
What is renal bone disease?
It results in patients developing osteomalacia, osteoporosis and osteosclerosis
What is another name for renal bone disease?
Renal bone disease is also known chronic kidney disease mineral and bone disorder (CKD-MBD)
How do we treat renal bone disease in CKD patients?
The prescription of calcium supplements, vitamin D supplements and bisphosphonates
In CKD, which four opioids are preferred to administer for pain relief? Why?
Alfentanil
Buprenorphine
Fentanyl
Oxycodone
They are most appropriate given impaired renal function
What are the six complications of CKD?
Normocytic Anaemia
Renal Bone Disease
Cardiovascular Disease
Oedema
Peripheral Neuropathy
Hyperkalaemia
What is the most prevalent complication of CKD? How do we prevent this complication?
Cardiovascular disease
The prescription of statins (atorvastatin 20mg) and the encouragement of weight loss and exercise
What urinary casts are associated with CKD?
Waxy casts
When should urinary ACR be conducted? Why?
Morning
The ACR can be affected by factors such as dehydration, certain drugs, and vigorous exercise, which can cause elevated results and give false positives.
