Understanding Medullary Sponge Kidney (Cacchi-Ricci Disease)

Definition-

Cacchi-Ricci Disease is primarily known as Medullary Sponge Kidney (MSK). It is a congenital disorder of the kidneys.  Though it is present from birth, symptoms typically do not occur until adolescence. MSK occurs when the tubules in the kidneys do not properly form in the womb. This results in cystic dilatations of the collecting tubules in one or both kidneys. On imaging scans, this shows up as a “sponge like” appearance. 70% of cases are bilateral, which means MSK occurs in both kidneys.

Patients with MSK are at increased risk for kidney stones and urinary tract infection. They typically pass twice as many stones per year as do other stone formers. Over 55% of MSK patients report chronic kidney pain, renal colic, frequent stones and recurrent infections.

MSK was previously believed not to be hereditary but there is more evidence coming forth that may indicate otherwise. There is conflicting evidence as to whether this condition is of genetic origin.

This kidney disease is unique because patients are, for the most part told they are not candidates for transplant. Though MSK can cause sub-par kidney function, only 10% of patients suffer renal failure and require dialysis. This disease, however is listed as one of the top painful conditions according to the American Chronic Pain Association. Sufferers of this disease complain of symptoms such as: Constant flank pain, renal and bladder spasms, pain associated with stone passage, and frequent urination.

Though not present in all cases, a common marker for this disease is the formation of “Kidney Gravel.” These are small, sand-like stones that some MSK patients pass every single day of their lives. These grains cause frequent irritation in the urinary tract; which in turn causes pain, inflammation and leads to infection. This “sand paper” effect can also cause issues such as bloody urine, constant pain and interstitial cystitis in the bladder.

Diagnosis-

The standard diagnostic test most urologists use is called an intravenous pyelogram (IVP) An IVP is an x-ray examination of the kidneys, ureters and urinary bladder that uses iodinated contrast material injected into veins. An x-ray (radiograph) is a noninvasive test that helps physicians diagnose and treat medical conditions.

If severe enough, MSK can also be viewed on ultrasound and MRI scans.

Additional Testing-

Blood tests for calcium, phosphorus, uric acid, electrolyte levels, blood urea nitrogen (BUN) and creatinine levels to assess kidney function.

Urinalysis to check for crystals, bacteria, blood, and white cells.

24 Hour Litho-Link Urine Test.

There are also imaging tests that can determine if you have lodged or embedded stones.

Additional testing may include: Abdominal X-rays, intravenous pyelogram (IVP), renal ultrasound, MRI or CT scan.

Treatment

Being a rare disease, the treatment for MSK can vary. Diagnostic tests such as urine PH and stone analysis can help sufferers discover what type of stones their body makes and why. Over 50% of MSK patients create calcium stones.  Getting a urine PH test is essential to care with MSK because certain stones form in alkaline urine while others form in acidic urine.

Dietary interventions are also essential in the management of MSK.  Everyone is different and keeping a  Health Log Journal  will help you discover what helps or hurts your symptoms.

Some patients have found great benefit from avoiding chemicals such as citric acid. Patients with stones that form in alkaline urine have found relief from acidifying their urine to decrease stone formation.  Patients who created stones in an acidic urine have found benefit from eliminating acidic foods such as tomato sauce to manage their MSK.

Drinking adequate amounts of water is also key to managing MSK. This is more than hydration, some patients struggle to drink water with additives such as sodium bicarbonate. Be vigilant of what goes into your body. Your kidneys have to filter everything, be sure you are giving them the easiest job possible when they are already struggling to function.

Pain management is typically a necessary intervention in the treatment of MSK. Kidney stones are severely painful and most patients need some sort of pain relief.  Medications such as anti-spasmodics, urinary analgesics and narcotics can be prescribed to manage the agony of MSK. Pelvic floor therapy is also recommended.

With MSK, the tubules in the kidney are not fully formed so they struggle to complete the tasks the body needs.  No two people are the same and you should discuss all options with your urologist. Most patients require a combination of dietary changes, medications and physical therapy to manage MSK.

If you are suffering with Medullary Sponge Kidney (Cacchi-Ricci Disease) please know you are not alone.

For more information and resources, consider reading the book Chronically Stoned: Guide to winning the battle against kidney stones & urinary tract infections

Sources-

https://www.ncbi.nlm.nih.gov/m/pubmed/29468561/

https://www.kidney.org/atoz/content/medullary-sponge-kidney