Lab - Urinalysis

Urinary system includes?

Kidneys, ureters, urinary bladder, urethra

Function of urinary system?

Filter blood, eliminate waste, regulate blood volume/pressure (renin)/pH/metabolites(lactic acid)/electrolytes

Fibrous capsule

Protective layer on kidney

3 regions of kidney

Renal cortex, renal medulla, renal pelvis

Renal pyramids

In medulla

Renal columns

Extensions of renal cortex

Papilla of pyramid

Tip of pyramid, rains into minor calyx

Major calyx

After minor, bigger pools

Renal pelvis

Funnel-shaped tube that joins with the ureter

Nephrons

structural and functional unit of kidney (corpuscle and tubule)

Glomerulus

part of the renal corpuscle, fenestrated capillaries that filter blood

glomerular capsule

filtrate forms, outside of glomerulus

afferent vs. efferent arteriole

afferent goes into glomerulus, and is thicker

efferent leaves glomerulus, thinner

What is the renal tubule made of?

• Proximal convuluted tubule

• Nephron loop

• DIstal convoluted tubule

• Collecting duct

All modify filtrate formed in corpuscle

Urine

liquid containing metabolic wastes (mostly water w/solutes (urea, uric acid, creatanine))

Urinalysis

analysis of urine contents

Color of urine

responsible by urobilin, but other solutes/water content dictate concentration of urine

Clarity

can become more turbid/cloudy if bacteria are present in urinary tract

Smell

No strong odor, but:

• ammonia - UTI

• sweet - glucose/diabetes

• asparagus and coffee can contribute to smell

Leukocytes in urine

Inflammation or UTI, STI

Nitrites in urine

Cloudy, could be UTI

Protein in urine

kidney damage, high BP, injury (proteinuria)

pH in urine

most urine is slightly acidic, but can change due to diet/metabolic state

Blood in urine

(hematuria) may have leaked through the filter from kidney damage or menstruation

Specific gravity of urine

How much is in it, water is 1 for comparison, normal range is 1.005-1.030 (dehydration, any condition w/ solutes in urine)

Ketones in urine

Starvation/diabetes, ketonuria, use fatty acids to create energy, which creates ketones

Bilirubin in urine

liver damage

Glucose in blood

Those with diabetes can have high glucose in urine

2 types of nephrons

Cortical nephrons (shorter loop, more common)

Juxtamedullary nephrons (longer loop, less common, higher concentrated)