Hematuria / Stones - Russ Flashcards
(50 cards)
1
Q
What is the most common screening test for blood and protein in the urine?
A
Urine Dipstick
2
Q
When do false negative results occur with urine dipstick testing?
A
- Presence of formalin
- High urinary concentration of ascorbic acid
3
Q
When do false positive results occur with urine dipstick testing?
A
- Alkaline urine (pH > 9.0)
- Contamination with oxidizing agents used to clean the perineum
4
Q
How many RBCs per high power field is considered hematuria in adults? Children?
A
- Adults = 2 RBC/HPF
- Children = 5 RBC/HPF
5
Q
What are the four most common causes of hematuria?
A
- Transient unexplained
- UTI
- Stones
- Cancer (bladder, kidney, prostate)
6
Q
What are some less frequent causes of hematuria?
A
- Exercise
- Trauma
- Endometriosis
- cyclic hematuria
- Sickle Cell Disease
- Polycystic Kidney Disease
- Glomerular Disease
7
Q
What are some risk factors for urinary tract MALIGNANCY?
A
- Age >35
- Smoking history
- Occupational exposure to chemicals
- History of:
- gross hematuria
- chronic cystitis
- pelvic irradiation
- exposure to cyclophosphamide
- obesity
- HTN
- analgesic abuse
- chronic indwelling foreign body
- Alcohol may be protective!
8
Q
What three presentations could look like hematuria but is not hematuria because the urine supernatant is red after spinning a urine sample and the urine dipstick is negative for heme?
A
- Porphyria
- Phenazopyridine
- like Azo
- Beets
- due to red pigment = betalaine
9
Q
What are some historical clues to the diagnosis of hematuria?
A
- Concurrent pyuria and dysuria
- pyuria = pus in urine
- dysuria = painful/difficult urination
- Recent URI
- Family Hx of renal failure
- Unilateral flank pain with radiation to the groin
- Symptoms of hesitancy and dribbling
- Vigorous exercise/trauma
10
Q
How can you tell if the hematuria is glomerular vs. extraglomerular bleeding?
A
- Glomerular
- red cell casts
- proteinuria
- dysmorphic appearing red cells
- smokey brown or “coca cola” color
- Extraglomerular
- clots
11
Q
What is 50% of unexplained hematuria due to?
A
underlying glomerular disease
12
Q
Is microscopic hematuria in children worrisome?
A
NO
- Fairly common, transient
- 3-4% have positive dipstick for blood
- 6-15 yoa
- 1% have positive dipstick for blood after second UA
13
Q
What are the most common causes of persistent microscopic hematuria in children?
A
- Glomerulopathies:
- IgA nephropathy
- Alport’s syndrome (Hereditary nephritis)
- Thin basement membrane disease (Familial hematuria)
- Post-infectious glomerulonephritis
- Hypercalciuria
- urine calcium/creat >2
- Nutcracker syndrome
- left renal vein compression by the aorta and superior mesenteric artery
14
Q
How should you evaluate microscopic hematuria in children?
A
- Asymptomatic & isolated (no protein):
- benign
- just observe
- Asymptomatic with proteinuria:
- quantitate protein with a 1st void morning specimen for urine total protein/creatinine ratio
- normal <0.3
- measure serum creatinine
- consider nephrology referral if either are abnormal
- quantitate protein with a 1st void morning specimen for urine total protein/creatinine ratio
15
Q
What are some causes of symptomatic hematuria in children?
A
- Glomerular diseases
- Interstitial/tubular diseases
- Lower UTI
- Nephrolithiasis
- Tumor
- Vascular disease
- Gross hematuria:
- UTI
- Trauma
- Irritation of meatus or perineum
16
Q
What percentage of men will develop a symptomatic stone by age 70?
A
12%
17
Q
What percentage of women will develop a symptomatic stone by age 70?
A
5%
18
Q
Who is more likely to get a kidney stone:
Young vs. older?
Men vs. women?
White vs. Black?
A
- Older: rate of urolithiasis increases with age
- Men > women
- Whites > blacks
19
Q
What are the four types of stones?
A
-
Calcium = 80% of stones
- ***Oxalate = most common
- Phosphate
- Uric acid
- Struvite
- Cystine
20
Q
What are common symptoms of urolithiasis?
A
- Flank pain
- Abdominal pain
- Testicle/Labial pain
- waxing & waning pain
- Gross/microscopic hematuria
- Possible N/V, dysuria, urgency
21
Q
What are the treatment options for urolithiasis?
A
- Pain medications
- Hydration
- Alpha blocker (tamsulosin) = relax ureters
- Calcium channel blocker (nifedipine) = relax ureters
- Ureteroscopy
- Extracorporeal shock wave lithotripsy
- Endoscopic lithotripsy
- Pyelolithotomy
- flank incision
- Percutaneous nephrolithotomy
- with scope using guidewire
22
Q
What kind of stones have urine sediment showing both dumbbell-shaped, envelope-shaped, and needle-shaped crystals?
A
Calcium oxalate
23
Q
What are the risk factors for calcium stone formation?
A
- Increased calcium excretion = hypercalciuria
- Increased uric acid excretion = hyperuricosuria
- uric acid forms center of stone and calcium oxalate forms around
- Reduced citrate excretion = hypocitraturia
- Low urine volume
- Increased oxalate excretion
24
Q
What are three possible types of Idiopathic Hypercalciuria that predispose individuals to calcium stones?
A
- Absorptive hypercalciuria
- autosomal dominant trait
- increased absorption of calcium in GI → increased calcium excretion
- elevated Calcitriol levels
- Fasting (resorptive) hypercalciuria
- bone loss
- Renal hypercalciuria
- renal leak
- abnormal calcium reabsorption in the proximal tubule
25
What are five possible etiologies for Hypocitraturia that may predispose individuals to getting calcium stones?
* Chronic diarrhea
* Renal tubular acidosis
* Ureteral diversion
* High protein diet
* more acid that needs excretion
* Topiramate
* migraine medicine
\*\*\*Any disease that causes metabolic acidosis!
26
What can Hyperoxaluria be attributed to in the context of calcium oxalate stones?
* Diet - 10%
* Glycine metabolism - 40%
* Ascorbic acid metabolism - 40%
* Increased oxalate absorption
* low calcium diet
* absorptive hypercalciuria
* enteric hyperoxaluria (malabsorption of fatty acids and bile salts)
* Overproduction of oxalate = Primary hyperoxaluria
* RARE
27
What are three medical problems associatd with calcium stone formation?
1. Primary hyperparathyroidism
2. Medullary sponge kidney
1. abnormality in renal papilla → more susceptible to injury → crystals latch onto damaged tissue
3. Distal renal tubular acidosis
28
What is the appropriate metabolic work-up for diagnosing why calcium stones are forming?
* Plasma [Ca2+]
* Parathyroid hormone
* Electrolytes
* rule out metabolic acidosis
* Serum uric acid
* 24 hour urine collection
* volume
* Ca2+, Uric Acid, Citrate, Oxalate, Creatinine, pH, Na+, PO4
29
What dietary recommendations are appropriate for a patient with calcium stones?
* Fluid
* drink 2L+ of water per day
* Restrict salt intake
* Lower protein intake
* protein increases citrate excretion
* Continue Calcium intake!
* don't decrease dairy products → will make calcium stones worse
* Restrict Oxalate
* if calcium oxalate stones
30
What medicinal treatments are appropriate for calcium stones?
* Thiazide diuretics
* Potassium citrate or Bicarbonate
* Orthophosphate
* Allopurinol/Febuxostat
* decreases uric acid production and excretion
* Calcium carbonate
* take TUMS with meals
31
What type of stones are non-opaque (radiolucent) on plain films, comprise 5-10% of stones in the US & Europe, but are 40% of stones in hot/arid climates?
Uric acid urolithiasis
(Hot/arid climates → low urine volume & acidic urine pH)
32
How are uric acid stones diagnosed?
* Analyze stone material recovered
* Indirectly by demonstrating increased urine uric acid excretion
33
What is the treatment for uric acid urolithiasis?
* Fluids: drink \>2 L per day
* increase urine output
* Alkalinization of urine
* Allopurinol/Febuxostat
34
What type of stones produce "coffin lid" crystals in urine sediment and only form in alkaline urine?
Struvite Stones
| (Magnesium ammonium phosphate)
35
What urine pathology are struvite stones most associated with?
* UTI due to Proteus/Klebsiella (most commonly)
* urease producing organism
* Increased ammonia production
* Increased urine pH
* decreases solubility of phosphate
36
What is the treatment for Struvite Stones?
* Chronic administration of antibiotics
* Acetohexemic acid
* urease inhibitor
* ESWL/percutaneous nephrolithotomy
* most effective treatment
37
What kind of stone produces hexagonal crystals in urine sediment?
Cystine Stones
38
What is cystinuria?
* Impairment of cystine transport leading to decreased proximal tubular re-absorption and increased cystine excretion
* autosomal recessive trait
39
How is Cystinuria characterized?
* The amount of cystine excreted by the **parents**
* ****parents usually = asymptomatic heterozygotes
40
How are cystine stones diagnosed?
* Family Hx
* Hexagonal cystine crystals on urinalysis
* Measure cystine excretion
41
What is the medical treatment for cystine stones?
* High fluid intake: \>3 L/day
* Alkalinization of urine: pH \>7.0
* Restrict dietary Na+
* Drugs that attach to cystine → increase solubility
* Penicillamine
* Tiopronin
* Captopril
42
What are procedural treatments for cystine stones?
* Irrigation of renal pelvis via catheter with penicillamine or acetylcystine
* RESISTANT to ESWL
* very soft stones
* Percutaneous nephrolithotomy / ultrasonic lithotripsy
* CURE = renal transplant
43
When is medical treatment indicated for the first kidney stone?
* Only in patients with metabolically active stone disease
* formation of new stones
* enlargement of old stones
* passage of gravel
* multiple stones at presentation
44
What is the risk of having a symptomatic 2nd stone?
* 1 year = 15%
* 5 years = 35-40%
* 10 years = 50%
* Men \> Women
45
What is the recommended evaluation for the first kidney stone?
* Limited evaluation:
* dietary history
* plasma calcium x2
* consider CT scan with IV contrast
* looking for medullary sponge kidney
Increase fluid intake → 2+L/day
46
How do asymptomatic stones typically resolve?
* 50% required procedure
* 50% passed stone spontaneously
\*\*\*Need to balance the risk of symptoms vs. the risk of morbidity from ESWL
47
What are common complications of ESWL?
* Treatment of \<2 cm stones can lead to a 2-3% increased incidence of obstruction
* Reversibly damages blood vessels and tubules
* New onset HTN (8%)
* presumably due to renin release form focal areas of renal ischemia
* Impairment in renal function
* due to scar formation
* Residual calculi
* (particularly with struvite stones)
48
Does a complaint of red urine equate to blood in the urine?
NO
* Could be caused by:
* Beets
* Porphyria
* Azo
49
Does painless hematuria help narrow the DDx?
Yes
points towards malignancy
50
Does kidney function help in the DDx?
Yes
can differentiat between obstruction or glomerulonephropathies
