Labs on kidney stone/pyelo?

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In my setting, a work-up would include a history, physical, and usually a UA.

Additional work-up which I do on selected patients may include components of the following: a bedside renal and aorta ultrasound, blood testing, possibly a CT, and occasionally a KUB XR.

I'm not skirting the issue at all – you asked me how I would approach a given case and I told you. If a person with a history of uncomplicated renal stone comes into the ED with another presentation and UA consistent with a renal stone, I would presumptively treat them as a kidney stone and might do no testing other than a UA.

I generally opt to do some type of imaging for first time renal stones, as well as patients with history of complicated stones. UA's can be quite difficult to interpret, and Tis established that the presence of a kidney stone can cause leukocytes to be present in the urine, which do not equal an infection. Sometimes additional testing (blood testing, imaging, cultures, etc.) is necessary to determine whether an infection is present. Stable patients with small stones and a UTI would typically be discussed with our urologist on call, who may arrange follow-up, and they would be given a trial of outpatient therapy with return precautions for the ED.

I CT a lot of kidney stones, but I will add this article to the discussion:
http://www.nejm.org/doi/full/10.1056/NEJMoa1404446

For the residents too timid to get in the middle of an "attending brawl", I just put this out there - if I didn't know, what you wrote would confuse me. For me, it is straightforward - if the pt looks like a stone, UA, IV, 1mg Dilaudid, 4mg Zofran, 30mg Toradol, CT-A/P non-con (stone protocol - thinner slices), done. CT negative? Door (because people trying to screw me for drugs are sometimes GREAT actors, as they should be). I get to tell them about "epiploic appendicits" as a possibility. Look ill, too? (Like, febrile, look sick?) CBC, BMP (for the creatinine).

As a note to med students and residents, in the community, you will not gain the enmity of the nursing staff if you bundle your orders. Want to get on the bad side? Piecemeal your labs one at a time. Academics can do that, because no one expects efficiency in that realm. However, in my career, I have had one patient with whom I had an actual good discussion about the pluses and minuses of a CT, and the pt opted for it - for he was an interventional cardiologist, and he got complete relief from 30mg Toradol.

Likewise, a 20-something female with history of stones? Treated symptomatically (including pain meds), and explaining how I wanted to save her the radiation - mother complained that "she always gets an MRI" (yes, she wrote that). That's what happens. Can't win.

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Am I the only one that read that urology algorithm? No one commented on the fact that they consider LFTs a requirement in working up a kidney stone.....not a single person on here said they get LFTs.
 
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Am I the only one that read that urology algorithm? No one commented on the fact that they consider LFTs a requirement in working up a kidney stone.....not a single person on here said they get LFTs.

Oh, I call the staff Urologist to discuss every abnormal LFT result. Don't you?
 
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Am I the only one that read that urology algorithm? No one commented on the fact that they consider LFTs a requirement in working up a kidney stone.....not a single person on here said they get LFTs.

I read it and just assumed the GOBSAT who authored the algorithm were all having a stroke.
 
I just don't understand this. All sorts of subspecialties want to dictate emergency care when they have little if any experience in emergency care. Urologists don't see the vast majority of kidney stones; cardiologists don't see the vast majority of chest pain; ortho doesn't see fractures; etc. The fact that a subspecialists could testify against an ER doc should be criminal.

Further, flomax in kidney stones makes me crazy. The preponderance of evidence shows no benefit and there is potential for harm. Why not just throw everyone on a drug that causes orthostatic hypotension and doesn't help? What happened to "First, do no harm?" That's bad medicine.

Multiple RCTs have shown that alpha blockers increase chances of stone passage (by about 50%), decrease the time to passage, and decrease analgesic use. Patients with distal ureteral stones benefit most as the highest concentration of alpha receptors is found in the distal ureter. This isn't controversial.

We use tamsulosin as the alpha-blocker of choice because of its high selectivity and extremely good side effect profile. The incidence of symptomatic postural hypotension on tamsulosin is 0.2% (1/502 in the drug trials).

The risk/benefit ratio is definitely on the side of medical expulsive therapy.
 
Multiple RCTs have shown that alpha blockers increase chances of stone passage (by about 50%), decrease the time to passage, and decrease analgesic use. Patients with distal ureteral stones benefit most as the highest concentration of alpha receptors is found in the distal ureter. This isn't controversial.

We use tamsulosin as the alpha-blocker of choice because of its high selectivity and extremely good side effect profile. The incidence of symptomatic postural hypotension on tamsulosin is 0.2% (1/502 in the drug trials).

The risk/benefit ratio is definitely on the side of medical expulsive therapy.

I respectfully disagree. There are many of us in EM who are underwhelmed by the poor evidence for alpha blockers in kidney stones.
 
No urology residents at my hospital so they admit no one unless its a simple post op patient.

It was amusing seeing academic urology standard of care because our urologists will tell us to send a febrile pt w wbc 20k and a uvj stone to clinic tomorrow after fluids and iv abx. They have essentially no interest in anything that is an elective outpatient procedure. If the pt is discharged then bounces back septic uro isnt responsible anyway so why would they make work for themselves by doing an admission?

If im worried about an infected stone pt i just admit them to the hospitalist. When uro calls back 2-3 hrs later i just let them know to see the pt in am.

We start flomax on discharged stone pts wo contraindication, rarely talk to uro about anyone i discharge because they take too long to call back.
 
I respectfully disagree. There are many of us in EM who are underwhelmed by the poor evidence for alpha blockers in kidney stones.
There is better evidence for alpha blockers in stones than there is for most things we do. Multiple RCTs and several meta analyses is pretty good in my book. Tamsulosin is cheap and safe. I don't see a lot of downside. What are your concerns with the data?
 
There is better evidence for alpha blockers in stones than there is for most things we do. Multiple RCTs and several meta analyses is pretty good in my book. Tamsulosin is cheap and safe. I don't see a lot of downside. What are your concerns with the data?

http://emlyceum.com/2012/05/19/nephrolithiasis-answers/

http://thesgem.com/2014/04/sgem71-like-a-rolling-kidney-stone-a-systematic-review-of-renal-colic/

The best argument is probably made by Dave Newman which is only on a paid subscription website. The long and short of it is that most of the trials are very poor. Few blinded. As I'm sure you're aware with meta-analysis, crap-in, crap-out.
 
There is better evidence for alpha blockers in stones than there is for most things we do. Multiple RCTs and several meta analyses is pretty good in my book. Tamsulosin is cheap and safe. I don't see a lot of downside. What are your concerns with the data?
Pretty much what TimesNewRoman said. Also, I 've seen a couple of head bleeds associated with orthostatic syncope after starting tamulosin. I counsel my patients about the risk, but from the bouncebacks I've seen that's not a universal practice.
 
Here's my write-up on the evidence for alpha-blockers in renal colic:
http://www.emlitofnote.com/2014/04/sadly-inadequate-cochrane-review-of.html

I believe it probably works, but likely only benefits a subset of stones. The only high-quality evidence was neutral, though. Nearly all small studies. Few in the U.S. Basically junk science – but a lot of junk science that's reasonably consistent. Maybe I'll kick the nest and see if anyone's interested in doing a definitive trial at my next job.
 
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Dr. Swaminathan also has a good overview of the alpha-blockers/renal colic research at rebel em:

http://rebelem.com/use-tamsulosin-renal-colic-facilitate-stone-passage/

"This is a great example of systematic reviews and meta-analyses only being as good as the original studies that go into them. I always use the haircut analogy. I wouldn’t let a 5 year-old cut my hair. I also wouldn’t let five 5 year-olds cut my hair because five 5 year-olds don’t make a 25 year-old. Putting together a bunch of poor studies does not make a good study."
 
Maybe I'll kick the nest and see if anyone's interested in doing a definitive trial at my next job.[/QUOTE said:
Mind telling us what your next gig is?
 
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Kaiser PDX.

The EM research group is: KP-CREST
This is trivial, but, everyone in the faculty pictures is smiling. That is the first time I've ever seen that. Is that because they were told to smile for their pictures ("or else"), or are they all KP "Stepford wives"?

As I say, trivial.
 
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I admit the studies aren't extremely high quality. Nonetheless, there is a good physiological mechanism to explain why alpha-blockers work, and the available data does support their use. At best you can say the jury is still out. The negative studies cited in the above analyses are not powered to prove that alpha-blockers do not work.

I think you are demanding a pretty high standard of evidence for a very benign therapy. Despite anecdotal reports above, tamsulosin's side effect profile is pretty much as benign as a drug can get. There are high quality drug safety data that demonstrate that. Most of the drugs you prescribe in the ER probably don't have this level of evidence supporting their use for a given indication. The potential benefit is great, as those patients who pass stones due to alpha-blocker therapy are avoiding general anesthesia and surgery.
 
I agree with cpants.
 
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My practice:
First time stone- CT, UA, Renal Fxn
Repeat offender (assuming reasonably confident on clinical grounds)- UA, Renal Fxn
- if an abrupt worsening in renal fxn or infected urine, get CT to confirm stone and call Urology

To me, I'm mostly trying to figure out who needs Urology to put in a stent or manipulate that stone. Everyone else goes home. My urologists will go in if there's an abrupt rise in Creatinine or if it looks like a stone (or if I keep them in Obs for 12-24 hrs and they continue to have severe pain from a kidney stone). One of the posters above said they have seen abrupt rise in creatinine in a unilateral stone, and I also seem to catch a few of those every year (though I'm sure vomiting and dehydration are pretty major contributing factors in those cases).

I really don't see a major role for CBCs. I check the BUN and Cr on bedside "i-stat" machines, so the tests come back quick and don't really delay disposition too much.
 
We sometimes have some disagreement on when to use postrenal AKI with stone as grounds for uro consult. Theoretically: 3ish mm stone, distal ureter. Hydro. Couple days of sx. Not infected, WBC normal. Cr mid-1 range, bumped by 0.3-0.5 from baseline gotten just recently for unrelated reason, with GFR now 60. Stone very readily expected to pass by odds. Good symptom control at home. Reliable. On Flomax. Discharge with strict return precautions or call uro as is? Have some very different mindsets out here. My feeling is hold NSAIDs until resolved despite my love for them, fluids, discuss, discharge if agreeable without calling the dick farm, lots of po fluids. Some of ours call urology for less.
 
As another quick aside, here's an interesting study that just came out for Feb in Urology Gold journal:

Role of Tamsulosin, Tadalafil, and Silodosin as the Medical Expulsive Therapy in Lower Ureteric Stone: A Randomized Trial (a Pilot Study)

Materials and Methods
Between January 2011 and December 2012, 285 patients presenting with distal ureteric stones of size 5-10 mm were on consent randomly assigned to 1 of 3 outpatient treatment arms: tamsulosin (group A), silodosin (group B), and tadalafil (group C). Therapy was given for a maximum of 4 weeks. Stone expulsion rate, time to stone expulsion, analgesic use, number of hospital visits for pain, follow-up, and endoscopic treatment and adverse effects of drugs were noted. All 3 groups were compared for normally distributed data by the analysis of variance, Bonferroni or Kruskal-Wallis test, and Mann-Whitney U test, as required. All the classified and categorical data were analyzed for all 3 groups by using the chi-square test.

Results
There was a statistically significant expulsion rate of 83.3% in group B compared with 64.4% and 66.7% in groups A and C, respectively, with lower time of stone expulsion (P value = .006 and P value = .016, respectively). Statistically significant differences were noted in colicky episodes and analgesic requirement in group B than groups A and C. There was no serious adverse event.




Again, not a perfect study, but it is a pilot study and has some interesting results...not that anyone here is going to start giving rapaflow (or that it'd be covered necessarily), but interesting to say the least
 
Talk about it in my blog post later today. Pretty good study. Doesn't close the door on large, distal stones – I think there may yet be some benefit hidden in there, but the magnitude would be small. Something like an NNT of 20 or so.
 
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Talk about it in my blog post later today. Pretty good study. Doesn't close the door on large, distal stones – I think there may yet be some benefit hidden in there, but the magnitude would be small. Something like an NNT of 20 or so.

I just read your post and popped into this thread to tell the previous poster to check your post for your opinion. I guess I don't need to do that, and I apologize for the previous sentence.
 
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