Russ- Hematuria Flashcards
What is the most common screening test for blood and protein in the urine?
Urine Dipstick Test
How does a urine dipstick test work?
A strip for blood uses Hydrogen peroxide which catalyzes a chemical reaction between Hb and the chromogen tetramethylbenzidine
What can cause false negative results on UDT?
Formalin
High urinary concentration of ascorbic acid
What can cause false positive results on UDT?
Alkaline urine (pH> 9) Contamination with oxidizing agents used to clean the perineum
What is abnormal hematuria in Adults? Children?
1 RBC/ high power field
5 RBC/ high power field
What are frequent causes of hematuria?
- transient unexplained- mCC
- UTI
- Stones
- Cancer (bladder, kidney, prostate)
what are less frequent causes of hematuria?
Exercise (marathons) trauma endometriosis sickle cell disease PKD Glomerular disease
What are risk factors for UT malignancy?
>35 smoking hx exposure to chemicals obesity/htn pelivic irradiation
How should you proceed if you have a patient with red urine?
Obtain a urine sample and spin it.
What does it mean if the urine sediment is red?
hematuria
What does it mean if the urine supernatant is red?
NOT Hematuria
Need to dipstick for heme
What can cause a red supernatant dipstick that is ALSO negative for heme?
Porphyria- abnormal metabolism of Hb
Phenzaopyridine- UT anesthetic to help with pain
Beets
What is beeturia?
14% of pts
increased intestinal absorption (colon) and urinary excretion of hte red pigment betalaine
What is betalaine?
Redox indicator that’s protected by REDUCING agents like oxalate.
DECOLORIZED by ferric ions, HCL acid and colonic bacteria.
In what pt populations does beeturia more predictably occur?
Pts that are IRON DEFICIENCT, ACHLORHYDRIC (pernicious anemia), or eat a diet rich in oxalate containing foods.
What can cause a red supernatant dipstick that is POSITIVE for heme?
Myoglobinuria- plasma clear
Hemoglobinuria- plasma red
Hematuria, pyuria, dysuria
UTI
Hematuria + recent URI
Ig nephropathy
hematuria + family hx of renal failure
Hereditary nephritis
thin basment membrane disease
familial hematuria
Hematuria+ unilateral flank pain w/ radiation to the groin
Kidney stone
hematuria + sxs of hesitancy and dribbling
prostatism
hematuria + vigorous exercise/trauma
not uncommon
cyclic hematuria in women
endometriosis
What are signs of GLOMERULAR bleeding?
- Red cell casts
- Proteinuria
- Dysmorphic appearing red cells (RBC enter tubules and water/salt changes way that RBC appear)
- Smokey brown or coca cola colored urine
What are clots significant for?
NEVER from glomerulus–> d/t urinary collecting system source
What radiological test should you do in a pt with hematuria?
CT scan of abdomen and pelvis*
What causes 50% of unexplained hematuria?
underlying glomerular disease
What are unusual causes of hematuria?
AV malformations
Fistulas
Loin pain- hematuria syndrome (abnormal glomerular basement membrane w/ a possible association w/ intratubular crystal formation)
What is seen with loin pain?
Blood in the urine + unilateral flank pain w/o evidence of obstruction/infection.
Biopsy–> abnormal GBM
How common is microscopic hematuria in children?
2-4% have pos dipstick for plood: 1% after SECOND UA
*NOT that uncommon
What are the MCC of persistent microscopic hematuria in children?
- Glomerulopathies
- Hypercalciuria
- Nutcracker syndrome
What are common glomerulonephropathies in children?
Ig A nephropathy
Alport’s syndrome
Thin basement membrane disease
Post-infectious glomerulonephritis
What causes hypercalciuria? What is it indicative of
Urine Ca/crea > .2
KS when they’re adults–ratio >2 is right environment for stones
What is nutcracker syndrome?
Left renal vein compression by the aorta and superior mesenteric a–> increased venous pressure and hematuria
*asian children
How do you evaluate microscopic hematuria in children that is asymptomatic and isolated (no protein)?
It’s usually benign so just observe it
How do you evaluate microscopic hematuria in children who also have asymptomatic proteinuria?
- QUANTITATE protein w/ a 1st void morning specimen for the urine total protein/creatinine ratio (normal refer to nephrology
What are causes of symptomatic hematuria in children?
- glomerular disease
- interstitial/tubular disease
- Lower UT
- Nephrolithiaseis
- Tumor
- Vascular disease
- Gross hematuria: UT infeciton; trauma; irritation of meatus/perineum
What percent of men and women develop symptomatic kidney stones by age 70?
12% men
5% women
In what populations is the rate of urolithiasis increased?
- Elderly
- M> W
- W > B
*7-10/ 1000 hopsital admissions
What percent of KS are calcium? Are they more commonly oxalate or phosphate?
80%
Oxalate > phosphate
What are the sxs of kidney stones?
Pan that wax/wane
Higher stone–> flank pain
As stone moves done–> dilation of the ureter behind obstruction–> abdominal pain–> moves lower–> groin pain–> uretral/bladder junction–> testicle/labial pain
Gross/microscopic hematuria
N, V, dysuria, urgency
How do you diagnose KS? What is commonly used in the ER?
- Abdominal plain film (KUB) used for Ca stone
- Ultrasound of hte kidneys- individual w/ hx of KS to decrease radiation
- CT scan of abdomen/pelvis (in ER if they hadn’t had KS before)
How do you treat KS?
Pain medications
Hydration
Relax uretral smooth muscle: Alpha blocker (tamsulosin) Ca channel blocker (nifedipine)
What is ureteroscopy?
Use a scope to ascend from the urethra> bladder > ureter
Use a basket, lithotripsy or laser
What is extracorporeal shock wave lithotripsy?
Break up large stone so it passes w/ out obstruction
What is endoscopic lithotripsy used for?
staghorn calculi (large)
What does a calcium oxalate crystal look like?
dumbbell shape
or
under polarized light–> coarse, needle- shaped CaOxalate crystals
What are risk factors for calcium stone formation?
Hypercalciuria hyperuricosuria hypocitraturia Low urine volume Increased oxalate excretion
What does citrate do to calcium stones?
usually inhibits stone formation
What is the most common cause of hypercalciuria?
Idiopathic hypercalciuria
What causes idiopathic hypercalciuria?
- Absorptive hyperclaciuria- AD, elevated calcitriol levels–> increased Ca absorbed from kidneys
What is fasting hypercalciuria?
Movement of Ca from bones to blood stream to urine
What is renal hypercalciuria?
Renal leak (abnormal Ca reabsorption in the PT)
What cause hypocitraturia?
- Chronic diarrhea
- Renal tubular acidosis
- Ureteral diversion (leads to bicarbonate loss–> metabolic acidosis)
- High protein diet–> acidic urine–> low citrate levels
- Topiramate
What causes hyperoxaluria?
- Increased oxalate absorption: low Ca diet, absorptive hypercalicuria, enteric hyperoxaluria (malabsorption of FA and bile salts–observed w/ intestinal bipass surgery)
- Overproduction of oxalate: primary hyperoxaluria (genetic abnormality when there’s an overproduction of oxalate in the body, fairly unusual)
How does Ca affect oxalate?
Ca is a primary binder of oxalate in the intestine–> more Ca ingested–> more oxalate binded –> more excreted in the urine
What medical problems are associated with calcium stone formation?
- primary hyperparahtyroidism
- medullary sponge kidney
- distal renal tubular acidosis
What is medullary sponge kidney?
Abnormality at end of UT as it enters the papilla> reflux of urine > puts people at risk for cyrstallizaiton at the tip of hte papilla > KS form more easily
What causes distal renal tubular acidosis?
Pre-existing disorder that leads to KS formation
What type of labs should you do to evaluate KS?
- Plasma Ca concentration (make sure they don’t have primary hyper PTH)
- PTH
- Electrolytes- acidosis
- Serum uric acid- excessive UA in serum
- 24 hr collection: volume, Ca, UA, citrate, oxalate, cr, pH, Na, phosphorus
How do you tx KS?
- fluid- 2 L of water > dilute things that cause stones to form
- Salt-> drives Ca excretion; lower Ca excretion > low salt diet
- Protein> lower protein > limit acid load> drop citrate levels
- low ca > make oxalate more available and make problem worse
- Limit oxalate if high in urine
What medications are used to treat KS?
- thiazide diuretics> decrease Ca excretion in urine
- K citrate or bicarbonate > alkalinize urine to increase citrate excretion
- Orthophosphate> absorptive hypercalcuria> reduces Ca in intestine
- Allopurinol/febuxostat> decrease UA production > pts w/ high UA level and Ca stones
- Ca carbonate> used to bind oxalate in stomatch > prevents it from being absorbed
What stone most commonly occurs in hot arid climates? What does it look like on radiologic evaluation
Uric acid urolithiasis (40%)
5-10% of stones in US/Europe
Non-opaque
No demonstrable abnormality in uric acid metabolism
What causes uric acid urolithiasis?
- High conc of UA in urine
2. Acidic urine pH– more insoluble in acidic urine
How do you diagnose uric acid urolithiasis?
Analysis of stone material recovered
Indirectly by demonstrating increased urine UA excretion
How do you treat UA urolithiasis?
Allopurinol/febuxostat
Alklainize the urine
Urine output to be > 2 L /day
What’s another name for struvite stones?
Magnesium ammonium phosphate stones
Infection stones
What do struvite stones look like?
Coffin lid crystals
What conditions lead to struvite stones? What organism causes these conditions?
increased ammonia production
increased urine pH (decreased solubility of phosphate)
Urease producing organism (PROTEUS AND KLEBSIELLA) that breaks down urea to ammonia
What pts often get struvite stones?
Pts w/ chronic indwelling foley catheters
How do you tx struvite stones?
- chronic admin of antibiotics
- acetohexemic acid- urease inhibitor (slows down production of ammonia)
- ESWL/Percutaneous nephrolithotomy
What do cystic stone crystals look like?
Hexagonal
What causes cystinuria? What type of trait is cystinuria?
Impairment of cystine transport>
decreased proximal tubular re-absorption and increased cystine excretion
Autosomal recessive
What are the cystinuria subtypes and what are they characterized by?
Characterized by the amts of cystine excreted by parents phenotypes (usually asymptomatic heterozygotes)
1/1 parents excrete a NORMAL mat of cystine (mut on chrom 2)
II/II parents excrete LARGE amts
III/III parents excrete intermediate amts
What do cystic stones look like on x-ray?
- radio-OPAQUE (d/t density of sulfur containg molecules)
- fuzzy gray appearance–less radio-opaque than Ca
- usually discrete but staghorn can occur
How do you diagnose cystic stones?
- family hx
- hexagonal cystien crystals on urinalysis
- measurement of cystine excretion
What is medical therapy for cystic stones?
- High fluid intake >3 L/day
- Alkalinization of urine (pH > 7)
- Restriction of Na–> more reabsorption of cyteine
What medications complex cysteine molecules and make it more soluble and are used to treat cystic stones?
Penicillamine
tiopronin
captopril
What type of invasive therapy is used for cystic stones?
- irrigation of renal pelvis via catheter w/ penicillamine or actylcystine
- RESISTANT to ESWL
- Percutaneous nephrolithotomy/ultrasonic lithotripsy (soft so not as affective)
What can cure cystic stones?
Renal transplant> no longer have genetic abnormality in the kidney
When is medical treatment indicated after a first kidney stone?
ONLY in pts w/ metabolically active stone disease
Need to demonstrate: formation of new stones enlargement of old stones passage of gravel multiple stones at presentation
What is the rick of a symptomatic 2nd stone? Who is more at risk for a second, stone men or women?
15% at one year
35-40% at 5 yrs
50% at 10 yrs
MEN
How do you evaluate a first kidney stone?
- Plasma Ca x 2-> make sure they don’t have a parathyroid adenoma
- increase fluid intake (over 2 L/d)
- Consider CT scan w/ IV contrast (look for medullary sponge kidney)
- dietary hx
What percent of asymptomatic stones pass?
50%
What are complications associated wtih ESWL?
Obstruction
Reversibly damage blood vessels and tubules
New HTN
Impaired renal fucntion
Does a complain of red urine equate to blood in the urine?
Not necessarily!
Lab > centrifuge> supernatant vs. urine sediment
Does painless hematuria help narrow the differential diagnosis?
YES!
UTI/KS are usually symptomatic
What is kidney function and does it help in the differential diagnosis?
Normal > suggests that theres no obstruction that keeps kidneys from draining properly
What significance is there in the lack of proteinuria?
Lack> NOT form glomerulus