Chronic kidney disease Flashcards
What is chronic kidney disease?
- It is a progressive deterioration in kidney function due to a disease of the kidneys
- It involves the deterioration of nephrons and nephron function
- It shares risk factors with diabetes and cardiovascular disease
What is the glomerular filtration rate? What is it used for?
- The Rate at which plasma from the glomerular capillary is filtered
- GFR is a proxy for overall kidney function
How is nephron function measured?
- In kidney disease, serum creatinine is elevated
- Thus, the creatinine result is used to calculate the estimated GFR
- Urine micro albumin: measures the amount of albumin in urine. Under normal circumstances, there is no albumin in urine
What are the ranges for eGFR?
- An eGFR of >90 is normal
- An eGFR of <60 indicates loss of kidney function
- An eGFR of <15 kidney failure
What causes chronic kidney disease?
- Most common cause is diabetes mellitus
- Significant proportion caused by hypertension
- 20% due to glomerular disease & other renal problems: systemic lupus erythematosus
What are the four consequences of chronic kidney disease?
Lowers excretion
Lowers biosynthesis
Altered metabolism
Renal bone disease
Explain the impact of lowered excretion
- This increases the amount of salt and water retained. As a result, this causes hypertension
- High levels of phosphate, acid, potassium are retained →acid/base disorders and renal bone disease
- Wastes eg uraemic toxins are retained
Explain the impact of lowered biosynthesis
- EPO cannot be made. This results in anaemia
* Active vit D can be made
Explain the impact of altered metabolism
- Lipids cannot be processed: hyperlipidaemia
- Drugs/medications cannot be processed
- Insulin resistance
- Protein-energy wasting: damaged kidneys lose their ability to remove protein waste and it starts to build up in the blood
Explain the impact of renal bone disease
- Since calciferol cannot be turned into its active form, there is low absorption of calcium from the gut. As a result, the body releases the Parathyroid Hormone which initiates osteoclasts in an attempt to regulate calcium levels
- When there is excess phosphate present, the body also releases the PTH to resorb calcium from bones and introduce it back to the body to offset this
What are some uraemic toxins? (3)
- Nitrogenous compounds: urea
- Low molecular weight proteins: PTH, TNF, various interleukins
- Solutes: Phosphate, calcium, aluminium
Define uraemic syndrome.
What are signs of uraemic syndrome?
A condition that affects the blood and blood vessels. It results in the destruction of platelets, low RBC count and kidney failure due to nephron damage
- Nausea and Vomiting
- Pruritus (chronic itchy skin)
- ↓Blood cell formation
- Immune suppression
- Platelet abnormalities
- Uraemic breath
- Xerostomia
What are the four ways kidney disease is managed?
Conservative treatment
Haemodialysis
Peritoneal dialysis
Renal transplantation
Explain conservative treatment for kidney disease.
- Focus is weight loss and ↓ blood pressure
- Common medications: ACE inhibitors, diuretic and sodium bicarbonate
- Low protein diet, fluid restriction
- Reduce cardiovascular disease risk factors
- Tx consequences, such as anaemia, bone disease
Explain hemodialysis for as a treatment for kidney disease
- A patient’s blood is circulated through a dialyser 3 to 4 times per week, for 3-4 hours at a time
- Patient attends a treatment centre
- Vascular access is gained through AV fistula or graft in forearm
