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Tag: kidney stones

Published on Leave a comment on Bacteria Found In Kidney Stones
Kidney stones Credit: Wikipedia

The incidence of kidney stones is on the rise worldwide, with 1 in 11 people expected to develop a stone at some point. There are several subtypes of kidney stones, with calcium oxalate (CaOx) stones occurring in more than 70% of cases. Recent research found live bacteria in calcium oxalate stones, along with biofilms.

Biofilms are communities of bacteria sticking to one another and coated with a protective slime. In these kidney stones, the biofilms were in-between mineral layers. Several bacterial species were most common in the kidney stones:  E. faecalis, P. mirabilis, and E. coli.

Prior to this study, calcium oxalate kidney stones were not considered bacterial. The researchers thought that the bacteria might explain why people tend to have recurrent kidney stones.

Kidney stones begin as tiny crystals that can accumulate and clump together in urine. One easy way to decrease risk of developing kidney stones is do drink plenty of water (want to dilute your urine). Low fluid intake and dehydration is associated with increased kidney stone formation, due to concentrated urine.

An interesting earlier study looked at the microbiome of the kidneys and found that the beneficial bacteria L. crispatus is found in the absence of kidney stones, while the presence of E.coli was associated with the development of kidney stones. The researchers found that the L. crispatus somehow blocked E.coli's ability to form kidney stones.

From Medical Xpress: Previously unknown bacterial component in kidney stone formation discovered

In an unexpected finding, a UCLA-led team has discovered that bacteria are present inside the most common type of kidney stone, revealing a previously unrecognized component involved in their formation. ...continue reading "Bacteria Found In Kidney Stones"

Published on Leave a comment on Kidney Stones and the Gut Microbiome
Kidney stones Credit: Wikipedia

What causes a person to develop kidney stones has long been debated. A recent study found that in persons who develop kidney stones, there are alterations in the gut, salivary, and urinary microbiomes. In other words, the community of fungi, viruses, and bacteria at each of these sites are out of whack or imbalanced.

In the study, not only were the 3 microbiomes imbalanced in the persons with kidney stones (when compared to healthy people without kidney stones), but they also had less diversity (fewer species) in their microbiomes. For example, persons with kidney stones had significantly fewer gut health associated bacteria F. prausnitzii, and significantly more inflammation associated E. lenta.

Those with kidney stones also had a history of having taken more antibiotics (antimicrobials).

The researchers conclusion: To avoid kidney stones a healthy diet is essential (for a healthy gut microbiome). One should also avoid taking antibiotics unless necessary. [BTW, the bacteria F. prausnitzii has long been viewed as a keystone microbe in a healthy gut microbiome. It can be increased by increasing fiber in the diet - e.g., fruits, vegetables, seeds, nuts, whole grains, legumes.]

From Medical Xpress: New study sheds light on the connection between the microbiome and kidney stones

A new study from Lawson Health Research Institute and Western University published in the journal Microbiome has found changes in the microbiome in multiple locations in the body are linked to the formation of kidney stones. ...continue reading "Kidney Stones and the Gut Microbiome"

Published on Leave a comment on Certain Foods Lower the Risk of Kidney Stones
Kidney stones Credit: Wikipedia

Kidney stones are not only incredibly painful, but are also associated with chronic kidney disease, osteoporosis, and heart disease. New research suggests a good way to prevent a recurrence of kidney stones is to increase consumption of calcium and potassium rich foods. Very simple!

The Mayo Clinic researchers also found certain dietary factors associated with a higher risk of getting kidney stones for the first time. They are: lower consumption of calcium, potassium, caffeine (e.g., coffee, tea), and phytate in the diet. As well as a lower daily fluid intake. Foods matter!

Some foods to eat to lower the risk of kidney stones:

Calcium rich foods: dairy products (e.g., cheese, milk, yogurt), dark green leafy vegetables (e.g., spinach, collard greens, broccoli, kale), and sardines. [Note: Calcium supplements are associated with kidney stones, while eating calcium rich foods is protective.]

Potassium rich foods: include legumes (beans and lentils), potatoes (with skins), tomatoes, some fruits (e.g., bananas, kiwi, orange juice, melons), dairy foods, some seafood (e.g., salmon, halibut, tuna, shad, clams), leafy greens (e.g., spinach), yam, squash.

Phytate rich foods: include beans, legumes, unprocessed cereal grains (e.g., oats), nuts, seeds, and potatoes.  Some people have referred to phytate rich foods as "anti-nutrients" and say to avoid them (because they may slow down absorption of certain minerals). However, recent research finds that the health benefits of eating phytate rich foods (e.g., they are antioxidants, anti-inflammatory) and other plant foods outweighs any concerns.

From Science Daily: Diets higher in calcium and potassium may help prevent recurrent symptomatic kidney stones

Kidney stones can cause not only excruciating pain but also are associated with chronic kidney disease, osteoporosis and cardiovascular disease. If you've experienced a kidney stone once, you have a 30% chance of having another kidney stone within five years.  ...continue reading "Certain Foods Lower the Risk of Kidney Stones"

Published on Leave a comment on Antibiotics and Kidney Stones

A recent large study (using health data from the United Kingdom) found that children and adults who took five commonly prescribed types of antibiotics had an increased risk of developing kidney stones, compared to people who didn't take these antibiotics. The five types of antibiotics were sulfas, cephalosporins, fluoroquinolones, nitrofurantoin, and broad-spectrum penicillins. The antibiotics were taken orally (by mouth).

However, not all antibiotics were associated with an increased risk of kidney stones. The study examined 12 types of antibiotics, and found seven types that didn’t appear to influence the risk of kidney stones.The strongest risks for kidney stones were in children and adolescents, and with more recent exposure. The risk of kidney stones decreased over time, but remained elevated several years after antibiotic use.

The researchers pointed out that recent studies have found differences in the gut microbiome (community of microbes) between patients with kidney stones and those without kidney stones. And that studies find that the use of antibiotics disrupts the microbiome. (here and here) Another reason to only take antibiotics when absolutely necessary. From Science Daily:

Oral antibiotics may raise risk of kidney stones

Pediatric researchers have found that children and adults treated with some oral antibiotics have a significantly higher risk of developing kidney stones. This is the first time that these medicines have been linked to this condition. The strongest risks appeared at younger ages and among patients most recently exposed to antibiotics.  ...continue reading "Antibiotics and Kidney Stones"

Published on Leave a comment on Sexual Intercourse Helps Pass Kidney Stones?

Yesterday's post on the possibility of riding "medium intensity" (think old fashioned) roller coasters to dislodge and pass kidney stones was amusing, but now I've read of another interesting way to facilitate passing of kidney stones. One study of Turkish men found that having sex 3 to 4 times a week promoted passage of kidney stones under 6 mm in size. Kidney stones are small, hard mineral deposits that form inside the kidneys, affecting up to 15 percent of people in developed countries.

All the men in the 3 groups (Sexual intercourse group, Tamsulosin group, and Control group) were also told to drink 2 liters of water a day to help expel kidney stones. Note that tamsulosin (also called Flomax) is a drug used to improve urination and to help with the passage of kidney stones. They found that after 2 weeks: 83.9% of the Sexual Intercourse group, 47.6% of the Tamsulosin group, and 34.8% of the Control group had successfully passed kidney stones, and after 4 weeks: 93.5% of the Sexual Intercourse group,  81% of the Tamsulosin group, and 78.3% of the Control group had done so. Frequent sex appeared to work, especially in speeding up the process! From the journal Urology:

Can Sexual Intercourse Be an Alternative Therapy for Distal Ureteral Stones? A Prospective, Randomized, Controlled Study.

OBJECTIVE: To investigate the effect of sexual intercourse on spontaneous passage of distal ureteral stones.

The patients were randomly divided into 3 groups with random number table envelope method. Patients in group 1 were asked to have sexual intercourse at least 3-4 times a week. Patients in group 2 were administered tamsulosin 0.4 mg/d. Patients in group 3 received standard medical therapy alone and acted as the controls. The expulsion rate was controlled after 2 and 4 weeks. Differences in the expulsion rate between groups were compared with the chi-square test for 3 × 2 tables. P <.05 was considered as statistically significant.

The mean stone size was 4.7 ± 0.8 mm in group 1, 5 ± 1 mm group 2, and 4.9 ± 0.8 mm group 3 (P = .4). Two weeks later, 26 of 31 patients (83.9%) in the sexual intercourse group, and 10 of 21 patients (47.6%) in tamsulosin group passed their stones, whereas 8 of 23 patients (34.8%) in the control group passed their stones (P = .001). The mean stone expulsion time was 10 ± 5.8 days in group 1, 16.6 ± 8.5 days in group 2, and 18 ± 5.5 days in group 3 (P = .0001).

Our results have indicated that patients who have distal ureteral stones ≤6 mm and a sexual partner may be advised to have sexual intercourse 3-4 times a week to increase the probability of spontaneous passage of the stones.

Published on Leave a comment on Ride A Roller Coaster To Pass Kidney Stones?

Image result for roller coaster wikipedia The most amusing study that I've read in a while, but hey, if it works - why not? Bottom line: Riding certain types of roller coasters (such as Big Thunder Mountain at Disney World) enables some people to pass kidney stones. Kidney stones are small, hard mineral deposits that form inside the kidneys, affecting up to 15 percent of people in developed countries.

The researchers made a model kidney (and used actual kidney stones and urine) and brought it on the roller coaster ride multiple times - and found that what they were hearing from patients was true. Riding the medium intensity roller coaster dislodged the kidney stones in many cases so that they can be passed. Can you imagine a prescription for kidney stones that says "Go ride a roller coaster"?  Note that "the ideal coaster is rough and quick with some twists and turns, but no upside down or inverted movements." From Futurity:

Roller coasters can jostle out kidney stones

Riding a roller coaster helps patients pass kidney stones with nearly a 70 percent success rate, research shows. David Wartinger, a professor emeritus in the department of osteopathic surgical specialties at Michigan State University, led both a pilot study and an expanded study to assess whether the stories he was hearing from patients were true. “Basically, I had patients telling me that after riding a particular roller coaster at Walt Disney World, they were able to pass their kidney stone,” Wartinger says. “I even had one patient say he passed three different stones after riding multiple times.” 

This resulted in Wartinger going out and testing the theory. Using a validated, synthetic 3D model of a hollow kidney complete with three kidney stones no larger than 4 millimeters inserted into the replica, he took the model in a backpack on Big Thunder Mountain at the theme park 20 times. His initial results verified patient reports. “In the pilot study, sitting in the last car of the roller coaster showed about a 64 percent passage rate, while sitting in the first few cars only had a 16 percent success rate,” Wartinger says.

The expanded study, conducted with Mark Mitchell, a Michigan State University resident at the time, included riding the same roller coaster with multiple kidney models attached to the researchers. They discovered even better results while sitting in the back of the coaster, with a passage rate of nearly 70 percent. They also found that both studies showed a 100 percent passage rate if the stones were located in the upper chamber of the kidney.

“In all, we used 174 kidney stones of varying shapes, sizes and weights to see if each model worked on the same ride and on two other roller coasters,” Wartinger says. “Big Thunder Mountain was the only one that worked. We tried Space Mountain and Aerosmith’s Rock ‘n’ Roller Coaster and both failed.” Wartinger went on to explain that these other rides are too fast and too violent with a G-force that pins the stone into the kidney and doesn’t allow it to pass. “The ideal coaster is rough and quick with some twists and turns, but no upside down or inverted movements,” he says.

Lithotripsy, which breaks apart kidney stones that are too large to pass, is a common treatment for the problem. Wartinger says the procedure is usually used in cases where the kidney stone is larger than 5 millimeters. “The problem though is lithotripsy can leave remnants in the kidney which can result in another stone,” Wartinger says. “The best way to potentially eliminate this from happening is to try going on a roller coaster after a treatment when the remnants are still small.” He adds that patients could even try going on a coaster once a year as maintenance, lessening the chances of future issues and minimizing health care costs. 

The original pilot study from the Journal of the American Osteopathic Association: Validation of a Functional Pyelocalyceal Renal Model for the Evaluation of Renal Calculi Passage While Riding a Roller Coaster

Published on Leave a comment on Calcium Supplements and Kidney Stones

Once again, a study finds that foods are superior to supplements (here calcium supplements). It appears that eating foods rich in calcium has protective effects against kidney stones, but taking calcium supplements may result in kidney stone growth.

On the other hand, vitamin D may prevent kidney stone formation. Reviewing studies over the past few years, it seems that vitamin D (the sunshine vitamin) is the one supplement with positive effects.

From Science Daily: Calcium supplements may increase the risk of kidney stone recurrence

Calcium supplements may increase the risk of kidney stone recurrence, according to a new study.

While eating foods rich in calcium has protective effects against kidney stones, the effect of supplementation with calcium and vitamin D on the risk of kidney stone formation remains unclear. To investigate, Christopher Loftus, MD candidate (Cleveland Clinic Lerner College of Medicine) and his colleagues reviewed the 24-hour urine collections and CT imaging scans from patients at their institution who had a history of kidney stones.

They identified 6050 patients with a history of kidney stones by imaging scans, 2061 of whom had 24-hour urine collections before and after starting supplementation. A total of 1486 patients were supplemented with calcium, 417 with vitamin D only, and 158 with no supplementation.

Patients who took calcium supplements had lower total calcium and oxalate (which are components of kidney stones) in their urine while blood levels were unaffected. However, these patients also had a faster rate of kidney stone growth suggesting that the mechanism of calcium supplementation on stone formation may not be straightforward. Vitamin D supplementation also decreased urinary calcium excretion as well as stone growth, suggesting that it may help prevent the risk of stone formation.

"While taking supplemental calcium has associated positive effects, these results suggest that supplemental, as compared with dietary, calcium may worsen stone disease for patients who are known to form kidney stones," said Loftus.