UROLITHIASIS Flashcards
kidney stones: ____________ affected more than ____________
men affected more than women
kidney stone prevalence increases with ________
age
kidney stone age of initial presentation
30s-50s
what are the 5 major types of kidney stones
1) calcium oxalate
2) calcium phosphate
3) struvite
4) uric acid
5) cystine
Stone formation is thought to be from
Supersaturation of calcium
stones Form in the _________and get extruded at the ________
interstitium
renal papilla
the most common kidney stone
calcium oxalate
RISK FACTORS FOR KIDNEY STONES
Areas of high humidity
Elevated temperatures
Incidence greater in the summer months
Sedentary lifestyle
High protein and salt intake
Genetic factors – particularly with the calcium stones
Examples: cystinuria, distal renal tubular acidosis (75% of pts)
most common risk factor for kidney stones
decreased fluid intake
urine composition & diet risk factors for calcium stones
Urine composition for Calcium stones
- Hypercalcuria
- Hyperoxaluria
- Hypocitraturia
Diet
- Low calcium intake
- High oxalate intake
- High animal protein intake
- High sodium intake
- Low fluid intake
risk factors for uric acid stones
Chronic diarrhea
Gout
Diabetes
risk factors for struvite stones
Urease-producing organisms
- Proteus & Klebsiella
- Form Staghorn calculi
symptoms of kidney stones
Acute and severe colic
May awaken pt from sleep
Localized to the flank
May be referred to the groin
May be associated with nausea and vomiting
Patients are writhing in pain trying to find a comfortable position
Urinary urgency, dysuria and frequency
(If stone becomes lodged at the ureterovesicular junction)
In men the pain may radiate to the tip of the penis
HEMATURIA
work up for kidney stones
- UA with culture
- urine pH
- CBC
- BMP (chem 8)
- pregnancy test
normal urine pH
5.8 - 5.9
which stone type is genetic
cystine
struvite stones are made of
magnesium ammonium phosphate
think proteus / klebsiella = think which stone
struvite (staghorn!)
urine pH < 5.5 = which stone/s
uric acid stones
cystine stones
urine pH 5.5-6.8 = which kidney stone/s
calcium oxalate stones
urine pH > 7.2 = which kidney stone/s
struvite or calcium phosphate stones
pts need to ________ their urine at home for analysis
strain
to catch stones
for recurrent stone formers (or family history) = do full metabolic work up
Serum PTH, calcium, uric acid, ‘lytes, creatinine, BUN
24 h urine collection
- Volume, pH, calcium, uric acid, oxalate, phosphate, sodium, citrate
DIAGNOSIS OF KIDNEY STONES
- CT/ultrasound
- KUB
CT and ultrasound will show obstruction and hydronephrosis
ultrasound = good cheap fast test for present of stone
what does KUB detect
only large radiopaque stones (calcium & struvite)
misses radiolucent stones
doesn’t detect obstructions
initial diagnostic test for kidney stones
ultrasound
common sites where kidney stones are lodged
- ureteropelvic junction (between kidney & ureter)
- as ureter crosses iliac artery
- ureterovesicular junction (between ureter & bladder)
narrowest point of urinary tract
ureterovesicular junction
medical emergency = Any obstructing stone with associated ___________
infection
acute therapy for kidney stones
IV hydration
Pain meds (ketorolac/Toradol, morphine)
Antiemetic (metoclopramide/reglan)
when to admit the pt for kidney stones
Intractable nausea and vomiting or pain
Obstructing stone with signs of infection
gold standard diagnosis for kidney stones
noncontrast abdomen/pelvic CT
REASONS FOR UROLOGICAL CONSULT FOR KIDNEY STONES
⦁ evidence of urinary obstruction
⦁ urinary stone with associated flank pain
⦁ anatomic abnormalities or solitary kidney***
⦁ concomitant pyelonephritis or recurrent infection
Which of the following is the greatest risk factor for kidney stone formation?
a. High sodium diet
b. Low fluid intake with low urine volume
c. Lower socioeconomic status
d. ETOH abuse
b. Low fluid intake with low urine volume
What type of stone composition is the most common? Select one: a. Uric acid b. Calcium oxalate c. Cystine d. Xanthine
b. Calcium oxalate
A 54 year-old female with a past medical history of headaches, left nephrectomy for cancer, and ovarian cysts presents to the ER after a motor-vehicle crash. A CT scan done revealed an incidental 4mm right ureteral stone. The patient is asymptomatic and no other findings are found. What is the best option for this patients ureteral stone?
Select one:
a. Send her home with Flomax and let her know she will pass this on her own
b. Do nothing since this patient is asymptomatic
c. Give her pain medication and send urine sample for culture.
d. Consult Urology
d. Consult Urology
- only has 1 kidney!
A 43 year old male presents to your office just recently passing his fourth stone. Which diagnostic test is most useful to identify the cause of his recurrent stone formation? Select one: a. UA dip with micro b. Renal biopsy c. 24 hour urine d. Urine cytology e. CMP
24 hr urine
A 48 year old female with a history of right flank pain on/off for 3 days and recent altered mental status presents to the ER. Her spouse reports that she has had fever/chills, dysuria, N/V, dark colored urine (that has decreased in the past 24 hours), and a history of nephrolithiasis. Her vital signs are BP 100/55, HR 115, RR 27, and Temp. 103.1. Imaging study confirms a 6 mm R obstructing ureteral stone. What is the next best step in the management of this patient?
Select one:
a. IV fluids, pain management, oral antibiotics, discharge to home and follow up with urology the following day
b. IV fluids, pain management, and Flomax.
c. Hospital admission for IV fluids, pain management, antibiotics and urgent urology consult
d. Oral pain management, antibiotics, and 24 hour urine collection
c. Hospital admission for IV fluids, pain management, antibiotics and urgent urology consult
infected!
CHANCES OF KIDNEY STONE PASSAGE 1mm 2-4mm 5-7mm 7-9mm >9mm
87% for 1 mm 76% for 2-4 mm 60% for 5-7 mm 48% for 7-9 mm 25% for stones ≥9 mm
RX to help with kidney stone passage
⦁ Tamsulosin 0.4mg qd
⦁ NSAIDS - Ibuprofen 600mg TID
⦁ Low dose prednisone 10mg qd x 5 days
Tamsulosin 0.4mg qd - alpha blocker - helps relax smooth muscle to allow stone to pass through more easily
THERAPEUTIC INTERVENTION IS NEEDED FOR KIDNEY STONES WHEN:
⦁ failure to pass stone in 4 weeks
⦁ fever, intolerable pain, persistent nausea or vomiting
SURGICAL TREATMENT FOR KIDNEY STONES
⦁ Ureteroscopy with stent placement
⦁ ESWL = extracorporeal shock wave lithotripsy
⦁ Percutaneous Nephrolithotomy (PNL)
PREVENTION OF KIDNEY STONE FORMATION
⦁ increase fluid intake** (most important)
⦁ avoid sodium
⦁ reduce animal protein consumption
⦁ limit foods high in oxalate (beer, tea, coffee)
STONE ANALYSIS - IF DUE TO HYPERCALCURIA
- Absorptive
⦁ Types I, II, III
⦁ Type I can be treated with Thiazides x 5 years or cellulose phosphate - Renal hypercalciuria
⦁ long term rx with thiazides - Resorptive
⦁ Hyperparathyroidism
STONE ANALYSIS
o HYPERCALCURIA
- Absorptive
⦁ Types I, II, III
⦁ Type I can be treated with Thiazides x 5 years or cellulose phosphate
- Renal hypercalciuria
⦁ long term rx with thiazides - Resorptive
⦁ Hyperparathyroidism
o HYPERURICOSURIC
o HYPEROXALURIC
⦁ chronic diarrhea from Inflammatory bowel disease
o HYPOCITRAURIC
⦁ persistent metabolic acidosis (Renal tubular acidosis, chronic diarrhea, chronic HCTZ)
almost all bladder stones occur in
MEN
bladder stones are ______ common than kidney stones
LESS
Most common bladder stone
URIC ACID STONE
Surface of bladder stones range from smooth & faceted to jagged & spiculated (_________)
JACK STONE
bladder stones (men) are usually due to
urinary retention secondary to BPH
RISK FACTORS FOR BLADDER STONES
⦁ bladder diverticulum ⦁ bladder outlet obstruction (Most common)** ⦁ Neurogenic bladder ⦁ UTIs ⦁ Catheters
MOST COMMON RISK FACTOR FOR BLADDER STONES
BLADDER OUTLET OBSTRUCTION
PRESENTATION OF BLADDER STONES
⦁ abdominal pain/pressure ⦁ hematuria or dark colored urine ⦁ difficulty urinating ⦁ urgency/frequency ⦁ interruption of stream ⦁ penile discomfort ⦁ UTI
physical exam for bladder stones
usually an enlarged prostate present (have BPH)
diagnosis of bladder stones
- bladder or pelvic xray
- cystoscopy
labs for bladder stones
⦁ UA with culture
TREATMENT FOR BLADDER STONES
- Cystoscopy in office for small stones
- Surgery
⦁ Cystolithalopaxy
⦁ Cystolithotomy
⦁ TURP
⦁ Simple prostatectomy - Potassium citrate