Renal Physiology Flashcards
(18 cards)
What is the basic functional unit of the kidney?
The Nephron
The nephron is responsible for renal physiology, including excretion and regulation of homeostasis.
What substances are primarily excreted by the kidneys?
Uric acid, urea, creatinine
These substances are waste products of metabolism that the kidneys filter from the blood.
What is the role of erythropoietin?
Stimulates red blood cell production
Produced by the kidneys, erythropoietin is crucial for maintaining adequate oxygen levels in the blood.
What is the significance of the glomerular filtration rate (GFR)?
Assessment of renal glomerular function
GFR is commonly measured to evaluate kidney function and diagnose renal disorders.
What does the proximal convoluted tubule primarily reabsorb?
- Sodium and water
- Potassium
- Phosphate
- HCO3-
- Glucose and amino acids
These substances are reabsorbed to maintain homeostasis and proper electrolyte balance.
What is the function of the loop of Henle?
Concentrates urine and reabsorbs NaCl
The loop of Henle plays a critical role in the concentration of urine and maintaining the osmotic gradient in the kidney.
True or False: The distal convoluted tubule (DCT) has minimal change in volume or concentration.
True
The DCT is involved in fine-tuning the reabsorption of sodium and secretion of potassium and hydrogen ions.
What triggers the release of Anti Diuretic Hormone (ADH)?
Increase in extracellular osmolality
ADH increases water permeability in the collecting ducts, aiding in water retention.
What are the two forms of Diabetes Insipidus (DI)?
- Central DI
- Nephrogenic DI
Central DI results from a lack of ADH production, while nephrogenic DI occurs when the kidneys do not respond to ADH.
What is the primary end product of creatine metabolism?
Serum creatinine
Serum creatinine is a key biomarker used to assess kidney function.
What factors can affect serum urea levels?
- Renal failure
- High protein intake
- Increased protein breakdown
- GI bleeding
- Trauma
- Surgery
Serum urea is influenced by various physiological and pathological conditions.
What is the definition of Acute Kidney Injury (AKI)?
Sudden decline in kidney function over hours to days
AKI leads to the accumulation of nitrogenous waste products and electrolyte imbalances.
What are the three types of AKI?
- Prerenal
- Intra renal
- Post renal
These types are classified based on the underlying causes of kidney dysfunction.
What characterizes Chronic Kidney Disease (CKD)?
eGFR <60 mL/min/1.73 m² for 3 months or more
CKD is marked by progressive loss of kidney function and can result from various causes such as diabetes and hypertension.
What is Nephrotic syndrome characterized by?
- Increased permeability of the glomerulus to proteins
- Massive proteinuria >2.5 g/day
- Hypoalbuminaemia
- Oedema
- Hypercholesterolaemia
Nephrotic syndrome results from various underlying conditions affecting kidney function.
Fill in the blank: The estimated GFR (eGFR) is based on ______.
[serum creatinine and sometimes cystatin C]
eGFR helps in detecting and staging chronic kidney disease.
What is the most accurate method to determine GFR?
Creatinine clearance
Creatinine clearance provides a better assessment of renal function compared to serum creatinine alone.
What are the limitations of serum creatinine as a biomarker?
- Unreliable early indicator
- Affected by muscle mass, diet, hydration
- Should be interpreted with eGFR
Serum creatinine levels can vary due to several factors, making it less reliable in isolation.
