Exam 2 Flashcards
(196 cards)
kidney stones - most common age group
70% of kidney stones occur between 20-50 yrs old
kidney stones - characteristics of pain
note: intra-renal stone (within the kidney) does not cause pain
kidney stones - types of stones
Calcium oxalate (80%): most common
Struvite (2-20%)
Uric Acid (6%): seen in younger women
Cystine 1(%): occurs only in patients with cystinuria
calcium oxalate stones - characteristic findings
most common
radio-opaque (can see on x-ray)
associated with hypercalcemia (high Ca++ in urine only) - primary hyperparathyroidism, malignancy, sarcoid
associated with hyperoxaluric states (high oxalates) - Crohn’s, jejunal ill bypass, high consumption of sweet tea
struvite stones - characteristic findings
cause staghorn calculi
triple phosphate stones: composed of phosphate, ammonium, magnesium
requires pH >7.2 and ammonia (caused by UTI)
proteus is most common organism
associated with foreign body (chronic catheter) or neurogenic bladder (spastic / not well controlled)
uric acid stones - characteristic findings
caused by super saturation of urine with uric acid
- gout patients get these
Radiolucent
Diet changes, allopurinol (med to dec uric acid), increased water intake prevent further stones
kidney stones - areas of impaction
Renal calyx
- stones get stuck here (cannot pass)
Ureteropelvic junction
UVJ-smallest diameter in the urinary tract
- most common site of impaction
kidney stone - sizes and ability to pass
<4 mm: 75% will pass
4 to 5 mm: 50% will pass
6 mm: 10% will pass
>10mm: require urologic intervention
Note: fully obstructed ureter can cause renal stasis
kidney stones - clinical presentation
colicy, severe pain on affected side
- pain in waves
- patient moves around a lot (cannot escape pain)
visceral pain caused by distention of ureter
nausea, vomiting, and pale color common
usually NOT hypotensive (shocky)
kidney stone location and site of pain
kidney = flank pain
proximal to mid ureter = flank pain, anterior abdomen to lower quadrant
UVJ (ureteral vesical junction) = labia, scrotum, groin region
Note: SUVJ and bladder stones may cause urgency, and dysuria as well as pain, or urinary retention
kidney stones - key history questions
Previous episodes of renal colic
Recurrent or Chronic UTI’s
Family history for hereditary disorders causing stones.
Immunocompromise
Solitary functioning kidney, or transplant (more concerning)
Bone pain, fractures (hyperparathyroidism = claim oxalate)
Gout, PUD peptic ulcer disease): uric acid stones
Diet, antacid use
suspicion of kidney stone - physical exam
vitals: tachycardia, elevated BP, tachypnea and diaphoresis
- hypotensive = concerned (not kidney stone)
Fever: suggests stone is infected
Flank tenderness, CVA tenderness
Abd: no point tenderness, pain not exacerbated with palpation
- must auscultate for bruits (AAA)
colicky flank pain - Ddx
AAA (often misdiagnosed as renal colic)
Renal Artery thrombosis/embolism
- seen in A fib or IV drug use
Testicular torsion
Ectopic pregnancy
Appendicitis
Cholecystitis
AAA - clinical presentation
misdiagnosed as renal colic
Caution: patients > 50 with flank pain, especially H/O tobacco, HTN, PVD (peripheral vascular disease)
A rupturing AAA may cause hydronephrosis (swelling of kidney) due to compression, and hematuria (ureteral irritation)
- white cells and red cells in urine since ureter is compressed and inflamed
renal artery embolus - clinical presentation
pain, hematuria and vomiting (intractable vomiting and pain)
- worse then a stone
risk factors: embolic disease (A-fib, PVD, IVDU)
Image: IVP (intravenous pyelogram, angiogram)
- non contrast CT will not give good info
Definitive study: arteriogram
Labs: CPK (elevated) - creatinine phosphokinase
ED role in renal colic
Relieve pain
Exclude life threatening diagnoses (AAA)
Provide appropriate disposition, follow up and instructions for returning
Not every patient needs a definitive diagnosis
ED treatment - renal colic
Hydration
- only if dehydrated or slightly hypotensive
Pain control before diagnostic tests
Analgesia: narcotics, anti-emetics (Zofran), or NSAIDS
NSAIDS: toradol (IV anti-inflammatory), ketorolac, diclofenac
benefits of NSAIDS to treat renal colic pain
non sedating
no ureteral spasm
no effect on hemodynamics
NSAIDS: toradol (IV anti-inflammatory), ketorolac, diclofenac
urinalysis and urine culture - renal colic
urinalysis and urine culture
- 10-30% will not have microscopic hematuria
- pyuria (WBCs) occurs due to inflammation or w/ bacteria infection
- crystals in urine may correspond to stone type (pH>7.6 proteus infection or RTA (renal tubular acidosis)
microscopic hematuria - what it means in kidney stones and acute cystitis (UTI)
magnitude of blood in urine does not correlate with size of obstruction, pain, or significance of infection
any localized inflammation may irritate ureter (causing hematuria) - e.g. appendicitis
laboratory studies - renal colic
urinalysis and urine culture
CBC: only if concerned about infection
Chem 7: prior to contrast study
SPT (serum preg test): prior to contrast study
passed stone - sent for evaluation
Chem 7 laboratory test
electrolytes, BUN, creatinine
order before contrast study
imaging for suspected renal stones - 4 functions
non-contrast CT
1) Confirms diagnosis
2) R/O other serious disorders
3) defines site of stone
4) Detects or R/O serious complications such as obstruction
imaging for suspected renal stones - who should be imaged
first time stone producers
history of IVDU
suspicion of serious disorder
Note: frequent stone formers who are not infected and symptomatically improve, do not require a study