Kidney Function and Clinical Chemistry

Flashcards covering key concepts and details related to kidney function and clinical chemistry.

What are the primary components of the urinary system?

Kidneys, ureters, urinary bladder, urethra.

Where are the kidneys located?

In the retroperitoneal space.

What is the functional unit of the kidney?

The nephron.

What are the main components of a nephron?

Glomerulus, proximal tubule, loop of Henle, distal tubule, collecting ducts.

What are the main functions of the kidneys?

Filter plasma, regulate fluid volume, regulate electrolyte concentrations, maintain acid/base balance, produce erythropoietin, produce calcitriol.

What do the kidneys filter from the blood?

Plasma and wastes.

What substances does the nephron conserve?

Sodium, chloride, bicarbonate, calcium, magnesium, glucose, amino acids, and water.

What substances are excreted by the nephron?

Urea, creatinine, potassium, hydrogen, ammonium, phosphate.

What happens during the initial filtration in the nephron?

Blood is filtered in the glomerulus.

What two layers form Bowman's capsule?

Parietal layer and visceral layer (podocytes).

What is the role of erythropoietin produced by the kidneys?

Stimulates red blood cell production.

What is calcitriol?

Activated form of vitamin D produced by kidneys.

What are the byproducts of protein metabolism measured in kidney function testing?

Blood Urea Nitrogen (BUN) and creatinine.

What does an increase in BUN indicate?

Decreased clearance by the kidneys or increased production.

What can cause an increase in BUN?

Gastrointestinal hemorrhage, protein-rich meals, and fever.

What does decreased BUN indicate?

Liver failure, malnutrition, or diuresis.

From where is creatinine synthesized?

In muscles from creatine and creatine phosphate.

Why is creatinine production considered constant?

It is produced at a constant rate in the body.

How is creatinine evaluated regarding kidney function?

Increased in azotemia or decreased in muscle mass.

What is azotemia?

Elevation of both BUN and creatinine.

What are the types of azotemia?

Prerenal, renal, and post-renal.

What causes prerenal azotemia?

Dehydration.

What causes renal azotemia?

Kidney disease.

What causes post-renal azotemia?

Outflow obstruction.

What is SDMA?

Symmetric dimethylarginine, a renal biomarker.

Why is SDMA important in diagnosing kidney disease?

It indicates kidney disease earlier than BUN and creatinine.

What is the significance of albumin levels in kidney disease?

Decreased due to protein leakage into urine.

What condition leads to proteinuria?

Renal failure causing increased proteins in urine.

Which electrolytes are commonly affected in kidney disease?

Mineral and electrolyte abnormalities.

What types of blood tests are performed to assess kidney function?

BUN, creatinine, SDMA, and urinalysis.

What does a high creatinine level indicate?

Possible azotemia indicating decreased kidney function.

How are urinalysis results interpreted in relation to kidney function?

To check for protein, cells, and other abnormalities.

What role does the glomerulus serve in the nephron?

Initial site of blood filtration.

What occurs in the proximal convoluted tubule?

Reabsorption of sodium, glucose, and amino acids.

What is the function of the Loop of Henle?

Concentration of urine by reabsorbing water and salts.

What does the distal convoluted tubule primarily regulate?

Electrolyte balance.

What is the collecting duct's role in kidney function?

Final concentration of urine and regulation of water.

What is evaluated when considering azotemia in a patient?

Both BUN and creatinine levels.

Why is monitoring kidney function crucial?

To prevent complications of kidney disease.

What nutritional consideration affects kidney health?

Protein intake, as it influences BUN levels.

What might a healthcare provider monitor following surgery or in chronic disease?

Kidney function tests for any signs of renal impairment.

What indicators suggest kidney issues detected through urinalysis?

Proteinuria, hematuria, and specific gravity.

What does a low specific gravity in urine imply?

Possible renal concentrating ability impairment.