CSI Case 9 Flashcards
What causes kidney disease?
- High blood glucose and blood pressure
- Leak
What are symptoms of kidney disease?
- swollen ankles, feet and hands
- blood in your pee (urine)
- feeling really tired
- being short of breath
- feeling sick.
How can reduce risk of kidney disease?
- Keep your blood sugar (glucose) levels within your target range
- Keep yourblood pressure down
- Get support to stop smoking
- Eat healthily and keep active
- Go to all your medical appointments.
What is ACR urine test?
albumin: creatinine ratio (ACR) looks for signs that protein is leaking into the urine
What is eGFR blood test?
creatinine level and other information (such as age, sex and ethnicity) are used to estimate your glomerular filtration rate (eGFR)
what tablets may be given?
Both ACE inhibitors and ARBs help to protect the kidneys from further damage, as well as lower blood pressure
What are the 3 components of the filtration barrier?
- Endothelial cells of glomerular capillaries
- Glomerular basement membrane
- Epithelial cells of Bowman’s Capsule (podocytes)
What are fenestrae?
- The glomerular capillary endothelium has many perforations calledfenestraewhich are pores about 70nm in size
- These pores actually do not restrict the movement of water and proteins or large molecules but instead is thought to limit the filtration of cellular components (eg: RBCs)
What surrounds the luminal surface of endothelial cells?
glycocalyxconsisting of negatively charged glycosaminoglycans which function to hinder the diffusion of negatively charged molecules
What is the basement membrane surrounding endothelium made of?
- collagentype IV
- heparan sulfate proteoglycans (restrict the movement of negatively charged molecules across the basement membrane)
- lamina
What layers do the basement membrane consist of?
- An inner thin layer(lamina rara interna)
- A thick layer(lamina densa)
- An outer dense layer(lamina rara externa)
What are podocytes?
specialised epithelial cells of Bowman’s capsule which form the visceral layer of the capsule
What projects from the podocytes?
- Foot-like processes project from these podocytes and interdigitate to form filtration slits
- These filtration slits are bridged by a thin diaphgram (the slit diaphragm) which has very small pores preventing large molecules from crossing. 3. Similar to the glycocalyx around the endothelial cells, negatively charged glycoproteins cover the podocytes, restricting filtration of large anions.
What is the filtration rate of molecules the same as?
charge across the filtration barrier is inversely related to their molecular weight
What is freely filtered and what is not?
Small moleculeslike glucose (180 Da) are freely filtered whereas albumin (69 kDa) is barely able to cross the barrier
What charge of the molecule filters better?
Negatively charged large molecules are filtered less easily than positively charged ones of the same size
What is the nephrotic syndrome triad?
- proteinuria
- hypoalbuminemia
- oedema
What happens in minimal change disease?
the glomeruli appear normal under a light microscope but under an electron microscope, the pathology of the podocytes can be detected
What also happens in minimal change disease again?
There is diffuse effacement of the foot processes of podocytes (causing the widening of filtration slits) and microvillous change seen on the podocytes
What is the treatment for minimal change glomerulonephritis?
- respond well to steroids but the symptoms may relapse if the patient comes off steroid therapy
- Some patients become steroid dependant but most do not progress to chronic renal failure and those that do usually have focal segmental glomerulosclerosis as well