Have questions about Loin Pain Hematuria Syndrome (LPHS)? Find clear, research-based answers below.
LPHS is a rare and poorly understood clinical disorder characterized by recurrent or persistent loin (flank) pain and hematuria (blood in the urine). Patients are typically young, predominantly women (70–80%), and Caucasian.
LPHS is a rare clinical condition affecting approximately 12 out of 100,000 people
LPHS is underreported and underrecognized, but there is no geographic variation.
As the name suggests, the main symptoms of Loin Pain Hematuria Syndrome (LPHS) include pain arising from the kidney (loin pain) and hematuria (blood in the urine).
The cause of primary LPHS is currently unknown and is the subject of our studies.
There is no specific diagnostic test for LPHS. It is a diagnosis of exclusion, meaning it is diagnosed only after other potential causes are ruled out. Evaluation typically includes clinical history, urinalysis, urine culture, blood tests, and imaging studies such as CT scans and nuclear medicine scans to exclude kidney stones, infections, cysts, tumors, and other conditions.
No, a kidney biopsy is not required.
The loin pain usually starts from either of the 2 kidneys. However, some of the patients eventually develop pain in both kidneys. Kidney function, measured by the glomerular filtration rate (GFR), usually remains normal or near normal. LPHS is not known to cause significant kidney damage and is unlikely to progress to dialysis.
Some clinicians believe LPHS may eventually resolve in many patients, and LPHS is uncommon in individuals over 60 years of age.
Because the cause of LPHS is unknown, treatment primarily focuses on symptom relief, particularly pain management.
Pain management options may include:
Our research focuses on a minimally invasive procedure called catheter-based renal denervation, which involves percutaneous radiofrequency ablation of the kidney sympathetic nerves. This procedure is performed at Regina General Hospital, the renal denervation center for the province of Saskatchewan, Canada. We have completed two prior research studies involving 16 patients using the Vessix™ Renal Denervation System (Boston Scientific, USA). Our feasibility randomized controlled trial, which enrolled 13 patients with LPHS using the Symplicity Spyral™ Renal Denervation System (Medtronic, USA), has also been completed and published. We are now working on the Tio-WGS study, the next phase of our research program.
A procedure that interrupts nerve signals between the kidney and brain to reduce pain.
Symplicity Spyral TM Renal Denervation System includes a catheter (very thin wire) and a generator. A catheter is connected to a radiofrequency generator and delivers controlled radiofrequency energy to the inner layers of the kidney's blood vessels. The energy (brief high temperature) then dissipates to the outer layers of the blood vessels to interrupt nerve impulses that communicate between the kidney and the brain. This interruption of these pathways leads to pain relief for variable time periods.
No. Since the renal denervation will take place under general anesthesia at our center, you are not allowed to drink or eat for 12 hours before the procedure.
What should I expect on the day of the renal denervation procedure?
You will be given general anesthesia by an anesthesiologist (a physician specializes in anesthesia care). General anesthesia is a treatment with certain medicines that puts you into a deep sleep, so you do not feel pain during the procedure. After you receive these medicines, you will not be aware of what is happening around you.
You might feel some immediate pain or discomfort after the anesthesia wears off. In MDRU, you will be given pain medications after the procedure as needed. Dull ache usually lasts for only a few hours to a few days.
The procedure typically takes around 45 minutes.
Effectiveness varies, but most patients show significant improvement.
No. Patients experience pain relief for variable time periods. Some patients experience recurrence of pain 6 months post-procedure (but still have lower pain scores than before the procedure). This finding suggests regrowth of the nerves along the kidney vessels.
There are a number of risks associated with catheterization, imaging, renal denervation, and general anesthesia. However, the overall safety analysis of renal denervation in previous studies from others and our group has been very positive. We have not identified any vascular complications in 60 patients who underwent the procedure over the last 8 years at our center.
Possible risks include:
As renal denervation is a relatively new procedure for LPHS patients, we have not noticed any side effects over the last 6 years.
There will be no cost to you if you wish to participate in the study involving renal denervation. There will be costs associated with traveling to Regina and staying for 24-48 hours.
Yes. If the feasibility LPHS study findings are promising, we will conduct a larger multi-center Randomized Controlled Trial with 64 LPHS patients.
Please stay in touch. We are trying to include other sites in other countries.
If the cause of primary LPHS is discovered, the disease can be eventually treated. This is what we are hoping to eventually achieve through our molecular research studies (proteomics and genomics studies). We plan to identify genetic signatures unique to LPHS patients by isolating DNA from patient blood samples and performing whole-genome sequencing. This approach will provide a comprehensive and quantitative measure of mutations associated with LPHS and will help us understand the reasons for the origin of pain in LPHS patients.
