“Hi, my name is Sharon, I’m filling in at this clinic as a physician assistant, until they can hire another permanent provider. What brings you in?”
“Oh man, I’ve had this back pain that just won’t quit. It’s on my left side and when it starts up I just want to scream, it hurts so bad. I’ve tried changing positions, nothing helps. It started last night. I really need help!.”
“Alright, are you in pain right now? You’re winching your face, is why I ask.”
“Yeah, the pain has started back up again.”
“So the pain comes and goes at any time?”
“Yeap, but now mostly it just stays, last night it did come and go somewhat.”
“Okay, have you taken anything for the pain?”
“I took some Motrin last night and this morning, it helped a little bit.”
“Are you having any blood in your urine, changes in your bowel habits, abdominal pain, nausea, vomiting or fevers?
“I started noticing my urine was turning pink last night and this morning it was just red. I’m not throwing up, nor do I think I have a fever.”
“Okay, have you had any previous history with urinary tract infections?”
“No, I don’t recall one.”
“Have you had any history of having kidney stones?”
As David squirmed trying to find a comfortable position to sit in, he answered, “No.”
“What medications are you on?”
“I take a blood pressure medication, I think it’s called lisinopril?? I also take something for this troublesome gout I get, when it occurs, which only happens about once, maybe twice a year.”
“Ah-ah, that could explain the possible cause of your back pain. I think you could have a renal stone, seeing that uric acid is the cause of your gout and it can also form renal stones.”
“Oh, no, are you serious?”
“ ‘fraid, so.”
I finished taking his history and then did his physical exam, which revealed he was quite tender to palpation over his posterior left side. He also had a swollen, red joint over his first toe on his right foot.
“David, how long has you toe joint been swollen?”
“Huh, oh yeah, It’s been like that since yesterday. But I forgot about it because my back is hurting so much.”
“Have you taken your medicine for your gout because of your toe?”
“Yeah, I started taking it last night, but I’ve only taken one dose, I’ve been too distracted by my back pain to think about my toe.”
High calcium level in the urine
10-12% incidence rate (i.e. 10-12% of all patients will have at least 1 renal stone episode in their lives)
Males > females
Diet: high intake of chocolate, spinach, green/black tea which can all increase the amount of oxalate in the system which then has to be excreted and can lead to stones
Genetic disorder (autosomal recessive genes)
Back or abdominal colicy pain
Blood in the urine
Possible crystals in the urine
“Okay, David I need you to give us a urine sample, get some blood drawn to assess your kidney function and then I’m going to send you over to the x-ray department for a CT scan of your abdomen and pelvis. I’ll have the nurse come in and give you something for your pain, so that you’re not squirming while you’re having your CT scan done.”
“Okay, thanks for the pain med.”
I left to find one of the clinic nurses and gave her the written orders to give David sixty mgs. of Toradol IM, draw the blood work and give him the specimen cup for his urine sample. After that she sent him over for his stat CT scan.
David was back in the clinic waiting room waiting for me to see him an hour later. So with the news that he was waiting, I walked over to the radiology department to check on his CT scan results. Thankfully the after-hours radiologist was still there and was willing to review the scan with me.
Dr. Earl, the radiologist asked, “you say, left sided pain?”
“Well here’s the reason for your patient’s pain. See this right here? He’s got a nice sized stone caught in his left ureter. I’d say it looks to be about 7 mm in size. Boy, does that have to hurt.”
“Well, the patient will agree with you there. Thanks for reading the CT scan for me.”
“No problem, that’s why we’re here.
I went back to the urgent care clinic and looked up his lab results. His kidney function was normal, as was his calcium and phosphorus levels. He had gross blood in his urine sample, but nothing else was out of whack except his specific gravity which showed his urine was concentrated.
Urine sample to assess for blood
CT scan (non-contrast) to look for the presence of a renal stone
Blood work to assess for kidney function, phosphorus, calcium, uric acid levels
Analysis of stone (if captured upon passage)
24 hour urine collection to assess for kidney function, urea, calcium, phosphate, citrate, sodium, oxalate, uric acid (usually done by the patient’s primary care physician at their follow-up appointment)
General Treatment Guidelines
Treatment of renal stones is based on what type of stone the patient has: stone composition can be either uric acid (10% of stones), cystine, or struvite (composed of magnesium and calcium, 10% of stones), or calcium oxalate (80% of stones).
All patients need fluid hydration, fluid hydration, fluid hydration
Tamsulosin or Nifedipine (either of which will help decrease muscular spastic pain from the ureters)
Most stones <7 mm can be passed with supportive help, if stone is not passed then patient has to be seen by urology who can then decide on shock therapy lithrotripsy, ureteroscopy (usage of a scope to retrieve stone), or open surgical procedure (nephrostomy).
Based on the type of stone patients can also be given potassium, sodium, or calcium supplements to help dissolve the stone.
I went to call David out of the waiting room, to have him come back into an empty exam room.
“Come in here, David, I have your test results back and I need to explain them.”
David walked gingerly into the exam room and sat down. “Thanks,” he said.
“I reviewed your CT scan you had done with the radiologist. Your CT scan shows you do indeed have a renal stone caught in your ureter, in other words the draining tube from your kidney to your bladder on the left side. It’s a sizable stone, 7 mm. So it may or may not pass on its own. Your uric acid level is quite high, it came back at 11, when normal is around 6. Your calcium and phosphorus levels are normal. So I do believe you have a uric acid stone. The stone has rough edges and this is why it hurts so much as your system is trying to pass it, every time it moves down your ureter, it goes into spasms and you end up in pain.”
“Wow, a little thing like a stone that small can cause this amount of pain? Oh, geez. What can I do about it?”
“Well, first let me ask a question. Your urine sample showed your urine was really concentrated. What quantity of fluids do you drink per day?”
“I thought I was keeping up with my fluids, but maybe not. It’s been really hot outside, seeing that it is summer. I’ve been working out 4 times a week to lose this extra weight I have put on. As a part of my trying to lose weight, I’ve been on a high protein diet.”
“That answers the reason you ended up with a renal stone. Your system is dehydrated, you’ve overloaded your system with purines, or protein to you, and you are somewhat overweight. So we need to push IV fluids on you and continue your pain medication. We’ll give you 6-8 hours of IV fluids here in the urgent care clinic as well as a medication called Tamsulosin which will help with the ureter spasms. I’ll also start you on allopurinol which you will have to take every day. The nurse will give you a cheesecloth to strain your urine with, in hopes of catching the stone. We need to send it in for analysis if you are able to pass it.”
“Okay, so you’re saying this stone I have will pass in the next few hours.”
“No, I’m hoping you pass it in the next few hours, but you may not. If you don’t then I’ll have to send you home with instructions to chug fluids at home, use the cheesecloth and continue taking the two meds I’m going to start you on. If you don’t pass the stone within the next 24 hours or so I’ll have to send you to a urologist who will have to schedule you for a procedure called, lithotripsy. Lithotripsy is where the urologist sends shock waves through your skin and into the stone to break it up so you can pass it. But let’s cross that road after you’ve had lots of IV fluids and see what happens.”
I walked with him down the hallway to our observation unit and gave the nurse his orders for intravenous fluids which would have potassium bicarbonate in it. Hopefully he would be able to pass the stone, but only time would tell. He was also given pain medications.
I went back to the clinic and started seeing other patients. At the end of my shift, I walked over to the observation unit and checked in on David. I found out that he still hadn’t passed the stone, but he did think it had moved a little bit, due to his continuing to have spastic pain, masked by the pain meds he was on.
“Okay, David it looks as though the IV fluids haven’t been successful in getting the stone to pass. I’m going to go ahead and discharge you home. You have to promise me that you will continue to chug fluids at home, take the prescription meds I gave you, i.e. the allopurinol, the pain medications and the tamsulosin. You need to come back tomorrow afternoon if you still haven’t passed the stone. You’ll know you will have passed it because the pain will be gone but right before you pass it you’ll have symptoms of needing to urinate frequently. This will be your bladder’s response to the presence of the stone in it. If you pass the stone, please make sure to bring it back into us so that we can test it for what sort of stone it is. Most likely it is a uric acid stone, but only the lab will be able to tell us with 100% certainty that it is.
“Okay, well I hope that I don’t spent the night in the bathroom, but I promise I’ll just continue to drink water until I can’t stand to look at it again.”
“Alright, I hope you have progress tonight.”
:So do I.”
The following afternoon, David checked back into the urgent care clinic. I saw him shortly after he arrived.
“Hi, David what’s happened?”
“I’m still having spastic pain and I’ve drank more water than I can stand. I don’t even want to look at it again.”
“Okay, am I to assume you still have back pain on the left side?”
“Alright, then let me go call the urologist who’s on call. He’ll come down and see you and then decide on how to proceed. I’ll be back shortly.”
I went out to the nurse’s station and paged the urologist. When he called back I told him what was going on with David, he said he’d be down to see him shortly. Thirty minutes later the urologist showed up and went into see David.
He came out a little while later and advised me that he was taking David up to the procedure room to do shock therapy lithotripsy. He wanted to get him up to the procedure room before the daytime urology nurses left for the day.
David was brought back down by one of the urology nurses to the urgent care clinic about 4 hours later. I could tell by the look on his face that the stone was gone.
“Hey, David you’re back. How did it go?”
“I’m free of that stone, at last! They put me in a big tub of water and then used some machine to break up the stone. I passed the stone in pieces about an hour after they put me in the tub. Boy am I glad it’s gone.”
“Well, I’m glad to hear it! Let me get that IV line discontinued for you and then you need your discharge orders. So hang tight, let me get the clinic nurse to take care of your IV line for you.”
After the clinic nurse removed his IV line, I went over his discharge meds. I told him he had to stay on the allopurinol every day, his lisinopril, and take the colchicine whenever he had another attack of gout. I also advised him to increase his daily fluid intake and to stop his high protein diet. I asked him to see his primary care physician in a few weeks for follow-up.
I checked his labs 3 days later and found out that the urologist had indeed sent the stone fragments in for analysis to the lab. The fragments were tested and they were indeed formed from concentrated uric acid. Hopefully with David on allopurinol and drinking lots of fluids he wouldn’t have another episode of renal stones.
Long-term prevention of renal stone re-occurrence
This is based on the type of stone the patient has.
All patients have to be taking in a high amount of fluids every day
Uric acid formers are put on allopurinol (which prevents uric acid formation)
Calcium stone formers can be advised as to dietary changes, and given diuretics which prevent the formation of subsequent stones.
All stone formers are advised as to a low sodium and low protein diet.