Hematuria (Russ) - W4 Flashcards
How does the urine dipstick identify blood?
strip for blood utilizies hydroen peroxide that catalyzes a chemical rxn between hemologin (or myoglobin) and the chromogen tetramethylbenzidine
What can cause false negatives or positives on the urine dipstick?
- positive = alkaline urine or contaminuation w/oxidizing agents
- negative = occurs in presence of formalin and high urinary concentration of ascorbic acid
What characterizes hematuria in adults and children?
- children = 5 red blooc cells/HPF
- adults = 2 RBC/HPF
What are some causes of hematuria?
- transient unexplained
- UTI
- Stones
- Cancer: bladder, kidney, prostate
- less frequent
- exercise
- trauma
- endometriosis
- sickle cell disease
- polycystic kidney disease
- glomerular disease
What does it mean if the urine sediment is red?
urine supernatant red?
- urine sediment red = hematuria
- urine supernatant red = not hematuria, need dipstick for heme
What can cause a red supernatant dipstick that is NEGATIVE for heme
- porphyria
- phenazopyridine
- beets
What if the red supernatant is POSITIVE FOR HEME?
- myogloinuria - clear plasma
- hemoglobinuria- plasma red
What causes the red color when eating beets?
betalaine pigment
What are 4 good indicators of glomerular bleeding?
- red cell casts
- proteinuria
- dysmorphic appearing red cells
- smokey brown or cola color
What is a good indicator of extraglomerular bleeding?
CLOTS
What test should you do if it’s the first incidence of hematuria?
CT scan of abdomen and pelvis
ultrasound if recurrenty
What are unusual causes of hematuria?
- AV malformations
- fistulas
- loin pain - hematuria syndrome
What are some causes of persistent microscopic hematuria in children?
- glomerulopathies: IgA nephropathy, Alport’s syndrome, thin basement membrane disease, post infectious glomerulonephritis
- Hypercalciuria
- Nutcracker syndrome - left renal vein compressed by aorat and superior mesenteric
What are causes of symptomatic hematuria in children?
- glomerular disease
- interstitial tubular diseases
- lower UTI
- nephrolithiasis
- tumor
- vascular disease
- gross hematuria - UTI, trauma
Who are stones (urolithiasis) more common in?
What are the symptoms?
- Men> women
- Whites > blacks
- risk increases w/age
- Symptoms
- flank pain
- abdominal pain
- testicle/labial pain
- wax and wane pain
- gross/microscopic hematuria
What are the most common types of stones?
How do we diagnose?
- 80% are calcium
- oxalate > phosphate
- diagnose = CT scan of abdomen and pelvis
What are risks for calcium stone formation?
- increased CALCIUM excretion
- increased URIC ACID excretion
- REDUCED CITRATE excretion
- low urine volume
- INCREASED OXALATE excretion
What is the most common cause of idiopathic hypercalciuria?
- absorptive hypercalciuria - autosomal dominant
- leads to elevated Calcitriol levels
What is shown in the image?
Calcium oxalate crystals
“dumbell and envelope shaped”
What can cause decreased citrate? Hypocitraturia
- chronic diarrhea
- renal tubular acidosis
- ureteral diversion
- high protein diet
- topiramate
How do calcium and oxalate work together?
Calcium binds to oxalate to prevent absorption.
If you’re not getting calcium, there is more oxalate exposed.
What are some metabolic problems seen with calcium stone formation?
- primary hyperparathyroidism - excessive calcium in urine
- medullary sponge kidney - abnormal papilla
- distal renal tubular acidosis - citrate issue
What is a good METABOLIC WORK UP for calcium stones
- plasma calcium concentration
- parathyroid hormone
- electrolytes
- serum uric acid
- 24 hour urine - volume, ca, pH, citrate, oxalate, creatinine, pH, sodium, phosphorus
Should you restrict calcium when treating calcium stones?
NO cuz oxalate would be unopposed
