About the flow - Ross Flashcards
What can start with intermittent to sever pain in the flank and radiate to the groin?
Nephrolithiasis.
A person presents in no position of comfort. They have intermittent severe pain in the flank. They are pale, diaphoretic but their vital signs are normal. They don’t happen to have blood in the urine. What is this?
Nephrolithiasis
What are stone mimics?
Renal artery infarction and AAA
Stones do not present first time in men >60 yo and do not cause hypotension.
What are stone risk factors?
Obesity, low volume urine, excess dietary meat (purine), excess dietary sodium, insulin resistance, metabolic syndrome, family history, gout, bowel surgery, primary hyperparathyrodism, prolonged immbolizatoin.
IBD - prone to elevated oxylate levels - leads to more stones.
80% of stones are?
Caclium oxalate or calcium phosphate
Supersaturation of dissovlved salts in the urine.
Struvite (mag/ammonium phosphate) make up ___% of stones.
10% of stones
Protease urea splitting bacteria (proteus, klebsiella)
Uric acid stones make up ___%. How do they appear on xray?
They make up 10% of stones. Gout patients develop stones that are radiolucent.
How do you diagnose nephrolithiasis?
UA: microscopic analysis sesnsitivity is 84% - hematuria is usually microscopic, but can detect pyuria as well
CBC: check for mild leukocytosisis up to 15k (look for bands)
BMP: Baseline Cr - during acute obstruction - no rise in Cr - Kidney elevates fxn.
Non-Contrast Ct - 100% sensitivity, 94% specificity
Plain abdominal radiography has a sensitivity up to 58% so for first timers you should get?
A non-contrast CT
A complicated stone is a kidney stone when someone has what?
Diabetes, HTN, single or horshoe kidney, or a kidney transplant.
or if they have an abnormal creatinine
These people need immediate imaging.
Those with a history of difficult stones get?
Stents lithotripsy.
In uncomplicated nephrolithiaiss and young what imaging and treatment should you give?
No need to image immediately, can be deffered until a f/u visit.
KUB (x-ray)
Tx: with pain meds and d/c
What’s an uncomplicated stone?
no infection
No hydronephrosis
normal Cr
Don’t CT
Obstructed stones can eventually raise what?
Creatinine
Where is the most commonly located stone? 2nd?
UVJ - uterovesicular junction - MC
Then pelvic Brim, also UPG (uteropelvic junction)
What are complicated stones?
Stones that cause infection - see this on a UA, potential bacteria or UA in urine
Stones that cause intractable pain
Stones that won’t pass (obstruction) based on size alone
- 98% < 5 mm pass within 4 weeks
60% pass that are 5-7mm
39% pass that are >7cm
What are some CT imaging indications?
First time presenters: older
Those with continued pain despite meds
Those you consider other dx
Non-contrast CT tells you what about stones?
Gives you size, location, and signs of infection.
Whats a presentation of pregnant women and kidney stones? Whats the first step?
Often a complicated presentation with hydronephrosis
First step is to use ultrasound - if hydronephrosis detected discuss with urology.
Possible low dose CT or MRI
A pregnant women is pain with a kidney stone, should you give her NSAIDs?
No - 1st trimester of pregnancy - vaginal bleeding.
Stones larger than __ mm need stenting. Or high grade obstructions/proximal stones.
Stones larger than 8-10 mm need stenting.
Infected stones need what treatment?
Close follow up with urology and treatement with abx.
2nd gen cephalosporin - cefuroxime
Fluroquinolone
As seen by WBC in urine sample - send culture.
Someone with a UTI (positive UA) and a stone will present how? What treatment do they get?
Obstructed: large stones, hydronephrosis, elevated Cr
Systemic illness - abnormal vitals and fevers.
All need IV antibiotics and urology consultatoin to remove stone/stent.
Someone with UTI and stones gets what abx? And for how long?
Ciprofloxacin, 500mg 14 days.
MAny times wbc in urine is inflammatory and not infection: no systemic signs of infection don’t need admission but still need treatment with abx.
How do you treat nephrolithiasis?
Treat pain aggressively with NSAIDs, IV lidocaine, IV narcotics
Manage nausea with antiemetics, and consider imaging study
Medical expulsive therapy doesn’t benefit stones smaller than?
6mm
What is medical expulsive therapy for nephrolithiasis.
Meds the relieve the spasm of the ureter.
Calcium channel blocker (Nifedipine 30 mg x 8 weeks)
alpha blocker are considered superior - tamsulosin .4mg daily x 3 weeks.
How long make it take to pass a stone? Should you try to catch it?
It may take 7-30 days to pass a stone.
Yes - strain urine to save stones as it is helpful to know what kind of stone ie calcium oxalate or uric acid stones.
People with kidney stones that are discharged should avoid?
caffeine, diuretics, excess Vit C
When should you admit a pt with nephrolithaisis?
Intractable pain or vomiting,
urosepsis,
one or transplanted kidney with obstructing stone,
ARF,
multiple co-morbidities
Consider if: fever, obsturcting stone with UTI.
How do you differentitate ebtween UTI vs Pyelonephritis vs Urosepsis?
UTI - infection of lower tract
Pyelonephritis: infection of upper tract (renal parenchyma)
Urosepsis: pyelo with Bactermia (lactate greater than 2.5)
3 complications of UTI?
Acute bacterial nephritis
Renal abscess
Emphysematous
How does someone with cystitis present? What are pitfalls to this presentation
Women know more often than men.
Pain with urination, frequency, burning.
Pitfalls: chlamydia gives same symptoms but no WBC in the urine.
Herpes can present this way.
Cystitis is?
Inflammation of the bladder = UTI
What are UA findings of cystitis? MC bacteria?
Hematuria
Pyuria (WBC)
Bacteria associated with infection is most often E.Coli
Leukocyte esterase in a UA tells you?
Detects the presence of luekocytes acting on bacteria - for UA of cystitis.
Presence of nitrites in the urine tells you?
Urinary pathogens convert nitrates to nitrites in the urine (presence of bacteria) this is ahigh positive predictive value of infection.
What is the treatement for cystitits?
Make sure not an upper tract infection first, then
Simple 3 day treatment - Treat with macrobid, keflex if pregnant or quinolone if not pregnant.
Offer candidial treatment
What is the time difference between complicated and uncomplicated cystitis treatment?
Uncomplicated - 3 days
complicated - 14 days.