Urine Flashcards
Principle constituents of urine
Water
Urea
Uric acid
Creatinine
Functions of kidney
Regulate water and inorganic ion balance
Remove metabolic waste products from blood
Remove foreign chemicals from blood
Secrete hormones
Gluconeogenesis
Hormones secreted from kidney
Erythropoietin, controls RBC production
Renin, controls angiotensin release
1,25 Dihydroxyvitamin D
Functional unit of kidney
Nephron
Capillary network of nephron
Glomerulus
Parts of tubule system
Proximal convoluted tubule
Loop of henle
Distal convoluted tubule
Glomurulus filters what from blood
Water Glucose Salt Urea Creatinine
80% of glomerular filtrate is reabsorbed where?
Proximal convoluted tubule
Concentrating segment of loop of henle
Descending loop, absorbs water
Diluting portion of loop of henle
Ascending loop active absorption of Na, Cl, Mg, Ca
Main functions of distal convoluted tubule
Maintain water/electrolyte balance by final reabsorption of sodium
Maintain acid-base balance by removing excess acid from body
ADH
Makes distal tubule and collecting tubule walls permeable to water in order to conserve it, increasing osmolality
Renal disease that are most often immunologically mediated
Glomerular diseases
Decreased urine output
Oliguria
Important finding in glomerular inflammation
RBC casts
Syndrome characterized by increased glomerular membrane permeability
Nephrotic syndrome, permeability results in massive proteinuria and excretion of fat bodies
Renal disease most likely due to toxic or infectious agents
Tubular disease
Disorder caused by defective secretion of H+ ions by renal tubules in presence of normal/near normal GFR
Renal tubular acidosis
Type 1 RTA
Distal type
Problem occurs in collecting ducts
Calcium carbonate drawn from bones in attempt to act as buffer
Type 2 RTA
Proximal type
Reduced bicarbonate reabsorption in proximal tubule, depletes bicarbonate content in blood and tissues
Group of inherited renal diseases
Fanconi syndrome
Renal disorder that effects tubules, interstitium, and renal pelvis
Pyelonephritis
Acute pyelonephritis
Sudden onset, flank pain, fever, malaise, WBCs and WBC casts
Pyuria
WBCs in urine
Chronic pyelonephritis
Chronic tubulointerstitial inflammation, renal scarring
May be caused by chronic obstruction by lesions or chronic reflux of urine due to anatomical abnormality
Thrombosis of renal vein characteristics
Clot formation, massive proteinuria, nephrotic syndrome, increased pressure
Cystitis
Infection of bladder
Anuria
Absence of urine
Renal calculi
Kidney stones, passage produces renal colic and hematuria, calcium oxalate most common constituent
Renal colic
Severe back pain radiating to groin
Acute renal failure classes
Abrupt deterioration of renal function
Prerenal occurs before blood reaches kidney
Renal occurs in kidney
Postrenal occurs after blood leaves kidney, usually due to obstruction
Chronic renal failure stages
Progressive loss of function,
1st decreased renal function, normal serum creatinine and BUN
2nd mild renal insufficiency
3rd frank renal failure with advancing anemia and acidosis
4th uremia, increased creatinine and BUN, acid base and electrolyte imbalance
Creatinine clearance formula
(Urine creatinine*total volume/1440)/serum creatinine
Normal creatinine value man/woman
Man: 107-139
Woman: 87-107
Advantages of creatinine clearance
Relatively constant amount produced endogenously
Freely filtered at glomerulus
Not reabsorbed in tubules
Disadvantages of creatinine clearance
Becomes increasingly inaccurate at lower filtration rates lower in females, elderly, small people because it is related to muscle mass
Correcting for body mass
(1.73/body mass) *GFR
Method of choice when precise GFR is required
Inulin clearance
Secretory function test of renal tubules reagent
Paraaminohippurate
Parts of nephron contained in cortex
Blood vessels
Glomerulus
Short loops of henle
Proximal and distal convoluted tubules
Parts of nephron contained in medulla
Long loops of henle
Collecting ducts
Fixed specific gravity of ultrafiltrate
1.010
Function of renin
Splits angiotensinogen into angiotensin 1 and other proteins
Angiotensin 1 function
Split by angiotensin converting enzyme aka ACE to form angiotensin 2
Angiotensin 2 function
Hormone which causes constriction of muscle in small arteries increasing blood pressure,
Triggers release of aldosterone from adrenal glands and ADH from pituitary
Aldosterone functions
Causes kidneys to retain salt and excrete potassium, salt causes water retention which increases blood volume and pressure
Changes in unpreserved urine
Color darkens, decreased clarity due to amorphous material or bacterial multiplication, Increased odor Increased pH Decreased glucose Decreased ketones, bilirubin, urobilinogen Increased nitrite Decreased RBC, WBC cells and casts Increased bacteria
Physical characteristics of urine reported on routine UA
Color
Appearance (clarity)
Specific gravity
Chief pigment in urine, other pigments?
Urochrome chief
Uroerythrin and urobilin
Amorphous material of alkaline urine
Phosphates and occasionally carbonates
Amorphous material in acidic urine composed of
Urates and uric acids
Components of normal urine which contribute most to specific gravity
Urea and sodium chloride
Normal range for specific gravity
1.003-1.030
Hyposthenuric
Specific gravity >1.007
Isosthenuric urine
1.010
Caused by chronic renal disease where concentrating and diluting ability is lost
Hypersthenuric urine
SG >1.020
Caused by proteinuria, dehydration or radiographic dyes
A urinometer must be corrected for what
Changes in temperature,
Presence of glucose and protein
Ammonia smell of urine indicates what
Bacterial growth
Sweet, fruity smelling urine incidents what
Presence of ketones
Polyuria
> 2000 ml of urine produced in 24 hours
Caused by excessive fluid intake, diabetes mellitus, renal disease effecting concentration ability
Term for any increase in urine volume
Diuresis
Griess test associated with which test on urine test strip
Nitrite
Diazomium salt reaction
Ketones tested on urine test strip
Acetoacetic acid
Acetone
Beta hydroxybutyric acid also a ketone but not tested by test strip
Test associated with lactose
Rubner’s test
Test for pentose
Bial orcinol test
Sucrose test
Thin layer chromatography
Constituents of normal protein excreted in urine
1/3 Tamm Horsfall glycoprotein
1/3 albumin
Remaining portion small globulins
Bence Jones proteinuria associated with what disorders
Multiple myeloma, macroglobulinemia,
Malignant lymphoma
Heavy proteinuria
3-4 g/day
Seen in nephrotic syndrome
Moderate proteinuria
1-3 g/day
Seen in renal diseases glomerular in nature and multiple myeloma
Bilirubin
Breakdown product of hemoglobin
Type of bilirubin filtered by glomerulus
Conjugated/direct
Water soluble
Urobilinogen
Breakdown product of conjugated/direct bilirubin
Test associated with urobilinogen
Ehrlich
Hemolytic jaundice characteristics
Increased urobilinogen
No change in bilirubin
Hepatocellular jaundice characteristics
Increased urobilinogen and bilirubin
Obstructive jaundice characteristics
Decreased urobilinogen and increased bilirubin
Increased indican associated with what
Small bowel bacterial contamination or abnormalities of GI tract
Oval fat bodies
Renal tubular cells or macrophages with globules of accumulated fat
Concentrating and diluting ability is measured with what 2 tests
Osmolality
Specific gravity
Urinometer temperature correction
Every 3C above 20 add .001 to SG
Every 3C below 20 subtract .001 from SG
Urinometer correction for glucose or protein
Every 1g/dL of protein or glucose subtract .003 from SG
Tamm Horsfall protein aka
Uromodulin
RTA produces urine of what pH
Alkaline urine
Ketones occur from complete or incomplete breakdown of fat
Incomplete
Reasons for increased fat metabolism
Diabetes mellitus,
Vomiting or diarrhea
Starvation
Dehydration
Glucose oxidase/peroxidase test used for what analyte
Glucose
Presence of what may mask positive reaction on glucose test strip
Ketones
Which sugar is not a reducing substance
Sucrose
Resorcinol used to test for what sugar
Fructose
Newborns screened for what reducing substance transferase deficiency at birth
Galactose, usually seen in people of middle eastern descent
Urine with black/brown appearance most likely due to
Melanin
Protein test strip sensitive only to what protein
Albumin
Error or pH indicators methodology used for what analyte
Proteins
Nitroprusside test used to test for which analyte
Ketones
Phenylketonuria characteristics
Seen in people of Scandinavian descent
Guthrie test used to test for
Presence of what in urine causes it to darken upon standing
Homogentisic acid oxidase
Fat globules seen in what disorder
Nephrotic syndrome
Severe renal disease
Watson Schwartz test used to test for what
Porphyrins
Confirmatory test porphyrins
Hoesch test
Sulkowitch test used for which analyte
Calcium
What disorder is suspected with more than 400 mg/24 calcium excreted in urine
Hyperparathyroidism
Type of cast associated with pyelonephritis
WBC
Hormone which controls Na/K pump
Aldosterone
6 sided crystal
Cysteine
Two non pathological crystals seen in acidic urine
Utica acid
Calcium oxalate
Non pathogenic crystals seen in alkaline urine
Triple phosphate urine
Ammonium biurate
Radiographic dye effect what specific gravity methodology
Refractometer
Doesn’t effect urinometer or test strip
Confirmatory tests for protein in urine
Sulfosalicylic acid
Heat and acetic acid test
Rhabdomyelosis
Myoglobin released in urine
Indican presence indicative of what
Bacterial overgrowth
Test for urobilinogen
Ehrlichs aldehyde reaction
Accumulation of homogentistic acid called what
Alkaptonuria
Principle means of waste product excretion in man
Urination
Minimal proteinuria