The Clinical Impact of Chronic Kidney Disease Flashcards
What is CKD?
CKD is characterized by the gradual decline in kidney function over months to years, leading to a build-up of waste and fluids in the body.
Common
What is acute kidney disease?
Less common and usually treatable if detected early.
What is the function of the kidneys?
Kidneys filter blood to remove waste products.
They maintain fluid and electrolyte balance by adjusting urine composition.
Regulate blood pressure by controlling blood volume.
Release hormones.
Metabolic waste eliminated.
Release erythropoitin for red blood cell production.
Maintain pH balance.
From beginning to end describe the structure of the nephron?
Renal corpuscle
Proximal convoluted tubule
Loop of henle
Distal convoluted tubule
Collecting dust
What are the parts of the renal corpuscle?
Glomerulus
Bowman’s capsule
What is the glomerulus?
A network of capillaries where blood filtration occurs. It is surrounded by Bowman’s capsule, which collects the filtrate.
What is the Bowman’s capsule?
A double-walled cup-shaped structure surrounding the glomerulus.
It collects the filtrate that is initially formed during filtration.
What is the proximal convoluted tubule?
The filtrate moves from Bowman’s capsule into the PCT.
What are the parts of the loop of henle?
Descending and ascending limb
What is the descending limb?
Permeable to water but not to ions. Water is reabsorbed passively, concentrating the filtrate.
What is the ascending limb?
Impermeable to water but actively transports ions (sodium, chloride) out of the filtrate, creating a concentration gradient in the surrounding interstitial fluid.
What is the distal convoluted tubule?
The filtrate travels from the loop of Henle into the DCT.
What is the collecting duct?
The DCT empties into the collecting duct, which passes through the renal medulla and collects urine from multiple nephrons.
What is glomerular filtration controlled by?
The balance between hydrostatic pressure in the glomerular capillaries, oncotic pressure in the blood plasma, and the permeability of the glomerular filtration barrier.
Regulated by factors such as renal autoregulation, sympathetic nervous system activity, and hormonal influences like angiotensin II and prostaglandins.
What is filtration pressure?
Capillary pressure – Bowman’s capsule pressure
What is the Glomerular Filtration Rate (GFR)?
Assumes free passage of water and small molecules
The volume of plasma filtered through the glomerulus per unit time
Corrected for body surface area
How to calculate glomerular filtration rate?
Volume of plasma cleared / unit time (min) / 1.73m2
What is creatinine?
Creatinine is a waste product produced by muscles from the breakdown of creatine, and it is filtered out of the blood by the kidneys and excreted in urine.
Where is creatinine synthesised?
Liver
What does creatinine production depend on?
Liver function
Muscle mass
Muscle catabolism
How is creatinine handled in the kidneys?
Filtration
Secretion
Reabsorption
How is filtration used in creatinine handling?
Freely filtered from the blood into the glomerular capillaries within the renal corpuscle.
How is secretion used in creatinine handling?
A small amount of creatinine is actively secreted from the peritubular capillaries into the renal tubules, particularly the proximal convoluted tubule (PCT).
This secretion process helps remove additional creatinine from the bloodstream and enhances its excretion in urine.
How is reabsorption used in creatinine handling?
Any small amount of creatinine that escapes filtration and secretion remains in the tubular fluid and is eventually excreted in urine.
How can serum creatinine be used as a surrogate marker of GFR?
Exponential relationship between Cr and GFR.
What is the issue with serum creatinine as a surrogate marker of GFR?
Does not account for muscle mass
What is an advantage of using creatinine to estimate GFR?
Easy to measure in blood and urine
How to calculate creatinine clearance?
[Cr]serum x Volume = [Cr]urine x Volume
What is haematuria?
Presence of red blood cells in the urine
What is gross haematuria?
Blood in the urine is visible to the naked eye, causing a noticeable change in urine colour
What is the microscopic Haematuria?
Microscopic haematuria is not visible to the naked eye but can be detected under a microscope during urine analysis.
What can haematuria caused by?
Urinary tract infections (UTIs)
Kidney infections
Bladder infections (cystitis)
Enlarged prostate gland (in men)
Trauma or injury to the urinary tract
Blood clotting disorders
What is the proteinuria?
Presence of excess protein in the urine.
What kinds of things contribute to proteinuria?
Kidney disease
Diabetes
High blood pressure
Infection
Medication
How to quantify proteinuria?
Urinalysis with dipstix
4 hour urine collection
Urine albumin and creatinine ratio
What are the features of G1 of CKD?
Haematuria, proteinuria, normal
GFR
What are the features of G2 of CKD?
Haematuria, proteinuria, mildly
reduced GFR
What are the features of G3 of CKD?
Moderately reduced GFR
What are the features of G4 of CKD?
Severe reduction in GFR
What are the features of G5 of CKD?
Kidney failure
What are the benefits of the KDOQI classification of CKD?
- Increased awareness of the public health impact of CKD
- Focused research initiatives
- Interest in early detection and prevention`
What are the drawbacks of the KDOQI classification of CKD?
- The classification is based on estimated GFR
- Equations used are increasingly inaccurate
- Over-diagnosis of CKD
What is the prevalence of CKD?
– 10.6% or women
– 5.8% or males
Why is the prevalence of CKD increasing?
- Increasing age of the population
- Diseases associated with CKD
- Increasing ethnic diversity in the population
What are the biochemical consequences of CKD?
- Hyperkalaemia
- Acidosis
- Hypocalcaemia and hyperphosphataemia
*Water retention fluid overdose
*Poor nutrition
*Iron deficiency
What is hyperkalaemia?
Unable to excrete dietary potassium
What is acidosis?
Inorganics acid produced during cell metabolism accumulates
Why id maintaining calcium homeostasis is essential for optimum kidney function?
Needed for bone health, muscle function, cell signalling, hormone regulation, and acid-base balance.
Dysregulation of calcium balance can lead to various health problems, including kidney stones, bone disorders, muscle weakness, and metabolic disturbances.
What is renal anaemia?
The kidney produces Erythropoietin in response to reduce oxygen delivery.
CKD can be considered a cause for anaemia.
What are the symptoms of CKD?
Accumulation of uraemic toxins
Fluid overload
Pain
Poor sleep and restless legs
Anaemia
Why is CKD so dangerous?
Associated with increase death for many other diseases.
