Clinical Microscopy Flashcards
major organic component of urine
urea
major inorganic component of urine
chloride (sodium comes second)
organic substances in urine
urea
creatinine
uric acid
glucose
proteins
hormones
vitamins
metabolized medications
inorganic substances in urine
chloride
sodium
potassium
sulfate
phosphate
ammonium
calcium
magnesium
muscular tube that connects the pelvis of the kidney to the bladder
ureter
cavity area that is an expansion of the ureter
functions to collect urine from the calyces for transport from the kidney to the ureter
renal pelvis
_____ supplies blood to the renal artery, which in turn provides blood to the kidneys and the renal vein which functions to return the blood to the _____
abdominal aorta
inferior vena cava
functional unit of the kidney
responsible for urine formation
comprised of a renal corpuscle and a tubular system
nephron
renal corpuscles consisting of the ___ and ____
glomerulus
Bowman’s capsule
tubular system
proximal convoluted tubule
loop of Henle
distal convoluted tubule
collecting duct
____ is a tuft of capillaries that lie in a tubular depression called ____
glomerulus
Bowman’s capsule
main function of glomerulus
filter the blood
carries blood into the glomerulus
afferent arteriole
carries blood away the glomerulus
efferent arteriole
proximal convoluted tubule is located in the ____
cortex
loop of Henle beings in the cortex with the ____ of the loop extending into the medulla where the bend of the loop that then becomes the ___ which ends in the cortex
descending limb
ascending limb
distal convoluted tubule is located in the ____, and join together to direct the urine flow into the ___
cortex
collecting duct
collecting duct joins with other collecting ducts forming a _____ to carry urine into a ___ of the renal pelvis
papillary duct
calyx
in order to form the excrete urine, three processes function together
glomerular filtration
tubular reabsorption
tubular secretion
glomerulus functions as a ___ to make an ultrafiltrate of plasma that is protein free
semipermeable membrane
GFR is about ____ of filtrate formed per minute by the glomeruli
renal tubules will reabsorb all but __ of the filtrate, which will be passed in the urine
115-125 mL
1mL
process by which filtered water, ions, and molecules leave the tubules for return to the blood via the peritubular capillaries
reabsorption
process by which a substance from the blood is transported across the wall of the tubule into the filtrate
secretion
responsibility for most of the reabsorption and secretion that occurs in the tubules
proximal convoluted tubule
limitation as to how much solute can be reabsorbed
renal threshold
renal threshold for glucose
160-180mg/dL
descending limb of loop of Henle reabsorbs ____
ascending limb of loop of Henle reabsorbs ___ and ___
water
sodium
chloride
DCT reabsorbs ___
sodium
controls the reabsorption of water in DCT
anti-diuretic hormone
in DCT, secretion of __ and ___ occurs
hydrogen ions
potassium
controls the reabsorption of sodium and water and secretion of K and H into the filtrate in DCT
aldosterone
final site for water reabsorption, to make urine more diluted or concentrated
collecting duct
controls the sodium and chloride reabsorption in collecting duct
aldosterone
in collecting duct, water reabsorption occurs by osmosis as well as in response to ___
ADH
secreted by the juxtaglomerular apparatus of the kidneys and catalyzes the conversion of angiotensinogen to angiotensin I
renin
stimulates the production of angiotensin II
a hormone in the inactive form
angiotensin I
regulates renal blood by constriction of renal arterioles and secretion of aldosterone from the adrenal glands to facilitate retention of sodium
angiotensin II
made in the cortex of the adrenal glands
acts on the kidneys by promoting the reabsorption of sodium from the filtrate into the blood and the secretion of potassium from the blood into the filtrate
water will be reabsorbed along with sodium
aldosterone
secreted by the posterior pituitary gland, promotes water reabsorption from the filtrate into the blood
primarily affects the reabsorption of water from the distal convoluted tubule and the collecting ducts
anti-diuretic hormone
promotes calcium reabsorption from the filtrate into the blood and excretion of phosphate ions from the blood into the filtrate
parathyroid hormone
alpha-globulin produced by the peritubular fibroblasts in the kidneys to stimulate red blood cell production in response to lowered oxygen levels
erythropoietin
inflammation of the glomerulus seen in children and young adults
can follow a group A streptococcus respiratory infection, characterized by hematuria, proteinuria, WBCs and casts (RBC, granular, hyaline)
acute glomerulonephritis
a more serious condition than acute glomerulonephritis that may result in renal failure; urinalysis results would be similar to acute glomerulonephritis
rapid progressive glomerulonephritis
inflammation of the renal interstitium that may be caused by an allergic reaction to medication
characterized by hematuria, proteinuria, WBCs and WCS casts
acute interstitial glomerulonephritis
thickening of the glomerular capillary walls and basement membrane
characterized by hematuria and proteinuria
membranous glomerulonephritis
may be caused by renal blood pressure irregularities
characterized by proteinuria (>3.5g/24h), hematuria, lipiduria, oval fat bodies, renal tubular epithelial cells and epithelial cell, fatty and waxy cts
nephrotic syndrome
affects a specific number of glomeruli, not the entire glomerulus, often seen in HIV patients
characterized by hematuria and proteinuria
focal segmental glomerulosclerosis
results in a long term progressive loss of renal function
characterized by hematuria, proteinuria, glucosuria, presence of casts, including broad casts
chronic glomerulonephritis (berger disease)
an infection of the renal tubules caused by a urinary tract infection
characterized by hematuria, proteinuria, WBCs, bacteria and WBC and bacterial casts
acute pyelonephritis
chronic infection of the tubules and interstitial tissue that may progress to renal failure
characterized by hematuria, proteinuria, WBCs, bacteria, and WBC, bacterial, granular, waxy and broad casts
chronic pyelonephritis
tubular necrosis caused by nephrotoxic agents and other disease processes, resulting in a failure of the kidneys to filter blood
renal failure
used to detect early renal disease
renal tubular reabsorption tests
examples of renal tubular reabsorption tests (also known as concentration tests)
osmolality
specific gravity
osmolar/free water clearance
measures the amount of solute dissolved in a solution
evaluates renal concentrating ability, monitor the course of the renal disease and monitor fluid and electrolyte therapy
osmolality
depends on the solute dissolved in a solution and the density of this solute
evaluates renal concentrating ability, monitor the course of the renal disease and monitor fluid and electrolyte therapy
specific gravity
used in the diagnosis of various types of diabetes mellitus
measures renal clearance of solutes and substance-free water
osmolar/free water clearance
tubular secretion or renal blood flow test uses p-aminohippuric acid, a substance that is infused into the patient
PAH is completely removed from the body, by a functional renal tissue
secretion test
used to assess renal waste removal and solute reabsorbing abilities
decreased rate indicates compromised kidney function
glomerular tests
used to assess glomerular filtrate rate
differ according to age and sex
values decrease with age
creatinine clearance
not changed by diet or rate of urine flow
creatinine levels
creatinine clearance formula
creatinine clearance = urine creatinine x urine volume per 24 hours / plasma creatinine
specimen of choice for creatinine clearance
24-hour time urine
uses only blood creatinine and MDRD (modification of diet in renal disease) formula
correction for gender and race required
results only reported as a number if <60ml/min/1.73m2
eGFR
determined by the body’s state of hydration
volume of urine
normal range of urine output in adult
1200-1500 mL/24 hours
decrease in urine output because of dehydration
oliguria
no urine output because of kidney damage or renal failure
anuria
increased urine output at night
caused by reduction in bladder capacity resulting from pregnancy, stones or prostrate enlargement or increased fluid intake at night
nocturia
increased daily output may exceed 2L/day
usually caused by such diseases as diabetes mellitus and diabetes insipidus, or ingestion of diuretics, caffeine and alcohol
polyuria
urine should be analyzed within ___ or preserve
2 hours
preserve urine: this will decrease bacterial growth but will cause precipitation of amorphous phosphates/urates
refrigeration
urine specimen types and collection times: concentrated specimen used for routine screening, pregnancy tests, and for detecting orthostatic proteinuria
first morning
urine specimen types and collection times: used for routine screening and microalbuminuria determination, time of collection not a consideration, patient cleans the external urinary meatus, urinates a small volume in the toilet and collects the rest of the voided sample
random midstream clean catch
urine specimen types and collection times: used for glucose monitoring usually the second voided specimen of the morning following this
fasting
urine specimen types and collection times: void 2 hours after eating, used to monitor glucose contet
2-hour postpandrial
urine specimen types and collection times: for creatinine clearance or for quantifying other analytes including sodium and potassium
24-hour
urine specimen types and collection times: collected from a tube placed through the urethra into the bladder, used for bacterial culture and routine screening
catheterized
urine specimen types and collection times: genital area cleansed with a detergent and urine collected in the middle of urination, used for bacterial culture and is the preferred collection method for routine analysis because it is the most concentrated sample of the day
midstream clean-catch
urine specimen types and collection times: needle inserted into the bladder through the abdominal wall; used for bacterial culture and cytologic testing
suprapubic aspiration
normal color of urine is derived from ___, which is a pigmented substance excreted at a constant rate
increased production can result from thyroid disease or a fasting urine sample
urochrome
formed from the oxidation of urobilinogen as urine stands, adds minimally to the normal yellow color
urobilin
colorless/pale yellow random specimen may indicate this condition as a result with increased urine excretion
diabetes insipidus or diabetes mellitus
this medication is prescribed for UTI resulting thick orange urine will mask chemical and microscopic analysis
pyridium (phenazopyridine)
red/pink urine may signify the presence of these in urine
blood, hemoglobin, myoglobin, porphyrins
these can cause green/blue urine
medications: amitriptyline, indicant and phenols
infections caused by pseudomonas
brown/black color may signify the presence these in urine
denatured hemoglobin
melanin
homogentisic acid
visual inspection of urines
clarity
urine clarity: indicates the absence of significant numbers of formed elements
clear
urine clarity: may be due to the presence of low numbers of formed eleements
hazy/slightly cloudy
urine clarity: in acid urine, may be due to amorphous urates showing a slight pink color, calcium oxalate crystals, or uric acid crystals; in alkaline urine, if the sample is white, may be due to amorphous phosphates and carbonates
cloudy
urine clarity: may be due to the presence of large numbers of formed elements
turbid
maple syrup odor in urine
maple syrup urine disease
sweaty or fruity odor in urine
ketone bodies (diabetic ketosis)
determines the kidney’s ability to reabsorb essential chemicals and water from the glomerular filtrate
detects dehydration and ADH abnormalities
density of a substance compared with the density of a similar volume of deionized water a similar temperature and is influenced by the number of particles dissolved and by the particle size
specific gravity
first renal function to become impaired
reabsorption
measures a refractive index by comparing the velocity of light in air to the velocity of light in a solution
does not require temperature corrections
refractometer
plasma filtrate entering the glomerulus has a SG of ___
1.010
normal random urine ranges from ___ (average)
1.015 - 1.025
fixed SG of 1.010 , indicates loss of concentrating and diluting ability
isosthenuric urine
SG < 1.010
hyposthenuric urine
SG > 1.010
hypersthenuric urine
SG: loss of the kidney’s ability to concentrate urine or presence of disease such as diabetes insipidus, glomerulonephritis and pyelonephritis, or normally if the person has a large fluid intake
low SG
SG: may result from adrenal insufficiency, diabetes mellitus, hepatic disease, congestive heart failure, and dehydration due to vomiting, diarrhea, low fluid intake, or strenuous exercise
high SG
method of choice for the chemical analysis of urine
used for the following tests: pH, protein, glucose, ketones, blood, bilirubin, urobilinogen, nitrite, leukocytes, creatinine, and specific gravity
reagent strips
acid-base balance of the body is primarily regulated by the ___ and ___
lungs
kidneys
provide regulation through secretion of hydrogen ions via ammonium ions, hydrogen phosphate and organic weak acid
facilitate reabsorption of bicarbonate from the convoluted tubules
kidneys
pH of urine ranges from __ for random urines and from ___ for the first morning void
4.5-8.0
5.0-6.0
acid pH in urine can be caused by:
high protein diets
after normal sleep
respiratory/metabolic acidosis
uncontrolled diabetes mellitus
alkaline urine can be caused by:
excreted after meals in response to gastric HCl
vomiting
increased consumption of vegetables
renal tubular acidosis
respiratory/metabolic alkalosis and UTIs
for urine pH, the reagent strip uses ___ to detect changes in pH
at pH 5.0, the pad is __ and __ at pH 9.0
methyl red/bromothymol blue
orange
blue
reagent strip uses ___ to detect protein in urine
indicator is ____ in the absence of protein and the pad changes from shades of ____ when abnormal amounts of protein (albumin) are present
tetrabromophenol blue
normal urine will contain less than ____ of protein or ____
10mg/dL
100mg/24 hour
tamm-horsfall
uromodulin
very diagnostic for renal disease and many indicate tubular reabsorption problems, increased low-molecular weight proteins, and glomerular membrane damaged caused by toxic agents, lupus or streptococcal glomerulonephritis
urine protein
produced due to proliferative disorder of plasma cells as seen in multiple myeloma
light chain monoclonal immunoglobulins
bence-jones protein
useful for patients with renal complications of diabetes mellitus
microalbumin evaluation
performed only for comparison with the protein level to rule out microalbuminuria
creatinine testing in a random urine