The world of probiotics is a wild one! And just like me, I’m sure that any renal dietitian who is reading this post wants to understand the why and how for recommending probiotics to CKD patients. Because above all, the health and safety of our patients is priority #1!
So let’s first unpack what the research says about how probiotic therapy may help with the dysbiosis associated with CKD. Secondly, we’ll uncover when to consider recommending probiotics and when to use caution.
If you missed the complementary post: A Renal Dietitian’s Guide to Fiber and Prebiotics, I’d recommend reading that post first. It provides an essential overview of the kidney-gut axis and the importance of fiber and prebiotics for kidney health.
Disclosure: This post is sponsored by Kibow Biotech, the producer of Renadyl, a probiotic for kidney health. As always, all opinions are my own.
Probiotics
Probiotics are defined by the United Nations’ Food and Agriculture Organization and the World Health Organization as “live microorganisms” that, when administered in adequate amounts, confer a health benefit on the host. (1)
By now, we understand the significance of dysbiosis in patients with CKD. And that leads to the question if the goal is increasing the number of beneficial bacteria in the gut to restore balance; why wouldn’t we go straight to the source and add probiotics as a targeted intervention?
How and when to recommend probiotics is a question that we’ve pondered a lot. And while probiotics are an excellent option for some patients, utilizing them alone in no way compares to the benefits gained from consuming a high-quality diet with various types of fiber and prebiotics.
What does the research say about probiotics for kidney disease?
The role of probiotics as a treatment for CKD is an emerging area of research. Although we see more and more studies on this topic, high-quality interventional studies are lacking. (2) So, what are the significant findings in studies so far?
- Reduction in uremic toxins and inflammatory markers
A meta-analysis conducted by Jia et al. reviewed the literature in human studies found that the primary conclusions of probiotics in the CKD population are reductions of PCS and the pro-inflammatory cytokine Interleukin-6 (IL-6). (3)
2. Decrease in serum CRP and reduction of gastrointestinal symptoms
Viramontes-Horner et al. conducted a small double-blinded, placebo-controlled, randomized clinical trial in hemodialysis patients. The trial compared a control group that received only nutritional counseling to the interventional group that received nutrition counseling and a symbiotic gel that contained Omega-3’s, vitamins, inulin, and L. Acidophilus and Bifidobacterium lactis.
The study’s primary outcomes included improvement in gastrointestinal symptoms and decreased serum CRP in the intervention group compared to the control. (4)
3. Decreased inflammatory markers and endotoxins and preservation of residual renal function in PD patients
A randomized, double-blind placebo-controlled study in PD patients found that patients receiving one capsule daily of Bifidobacterium bifidum A218, 109 CFU Bifidobacterium catenulatum A302, 109 CFU Bifidobacterium longum A101, and 109 CFU Lactobacillus Plantarum A87 for six months decreased the pro-inflammatory markers TNF-a, IL-5, IL-6 and preserved residual renal function compared to those who did not receive treatment (5)
4. Reduction in BUN, increased quality of life, and absence of adverse effects in patients with Stage 3+4 CKD
In 2010, Ranganathan et al. conducted a 6-month prospective, randomized, double-blind, placebo-controlled crossover trial in 46 patients with stage 3+4 CKD using a multistrain probiotic formula known as Renadyl. Despite the small sample size, the study’s primary findings were significant. The results included a reduction of BUN, improved quality of life, and no adverse outcomes. (6)
5. The SYNERGY study showed a decrease in PCS and favorable changes to fecal bacteria of patients with CKD stage 4+5
The Synbiotics Easing Renal Failure by Improving Gut Microbiology (SYNERGY) Study was a single-center, double-blind, placebo-controlled, randomized crossover trial investigating the effects of synbiotics in patients with moderate to severe CKD. The synbiotic supplement contained a mixture of both prebiotics and included nine different strains across the Lactobacillus, Bifidobacteria, and Streptococcus genera.
The study’s findings showed a significant reduction of PCS but not IS and an increase in the amount of Faecalibacterium found in the stool of the intervention group compared to the control group. Faecalibacterium is known to have anti-inflammatory effects and potentially reduce tryptophan which can induce IS production. (7)
Practical applications for probiotics
While these findings show exciting promise, probiotic therapy may not be necessary for all patients. Understanding which patients might benefit and what type of probiotics to use takes a lot of careful research and trial and error.
Let’s start by examining why probiotics may be helpful and when to use caution.
When to recommend probiotics
There are several reasons why a patient may benefit from probiotic therapy, even on a short term basis:
1. Following a course of antibiotics
In a literature review, the administration of S. Boulardii or L. acidophilus+ L. Casei showed a decreased incidence of C. difficile following an antibiotic course compared to a control group. (8)
While this review did not discuss the optimal timing of taking a probiotic with an antibiotic, it is a well-known practice not to take them simultaneously because the antibiotic may kill off the good bacteria.
When recommending a probiotic concurrently with an antibiotic, it’s best to advise patients to avoid taking them together. For example, when antibiotics are dosed in the morning and at night, it’s best to take a probiotic at lunch.
2. Patients with diarrhea, constipation or a combination of both may benefit from a trial of probiotics
There is mixed evidence that probiotics can help with IBS symptoms, and it is not clear which probiotic strain is superior. However, according to the Candian Association of Gastroenterology, a one-month trial to monitor for improvement or worsening symptoms is considered a supportive way to manage IBS. (9)
3. Chronic use of certain medications.
Proton pump inhibitors are well known to alter gut flora, and patients with long-term use may benefit from probiotic therapy. It’s important to note that several other common medications, including anti-depressants and statins, are also correlated with changes to the microbiome. (10)
4. Managing uremia and correcting CKD related dysbiosis
Probiotics can be a therapeutic strategy to decrease uremic toxins and nitrogenous waste and correct the dysbiosis associated with reduced renal function.
As kidney function declines, waste products such as urea, uric acid, and creatinine that are circulating in the blood wind up translocating to the colon, increasing uremic toxin load in the gut and causing a disruption in the normal bacterial flora.
Renadyl is a probiotic that consists of three bacterial strains. The bacteria were thoughtfully selected because of their ability to metabolize nitrogenous waste products. The three strains of bacteria include:
- Streptococcus thermophilus
- Lactobacillus acidophilus
- Bifidobacterium longum
When these bacteria act on nitrogenous waste as a source of food, it produces toxic metabolites. The toxic metabolites are removed from the body through stool, preventing uremic toxins from re-entering the bloodstream.
This targeted therapeutic approach is a way to use the gut as a means of “enteric or intestinal dialysis” and has the additional benefit of reinstating beneficial bacteria to the microbiome.
The benefits of using a probiotic that targets the unique needs of individuals with CKD include:
- Decreased symptoms of uremia
- Less burden on the kidneys due to circulating waste products
- Correction of dysbiosis commonly seen in patients with CKD
- Improved quality of life
- Decreased markers of inflammation, specifically C-reactive protein
To learn more about Renadyl, including success stories and additional research, visit the Kibow Biotech website.
What are some of the reasons to use caution with probiotics?
Several contraindications come to mind when we think of probiotics in the CKD patient population. However, when reviewing the research, the tables are turning as new research and evidence emerge!
Kidney transplantation
Historically it has been recommended that individuals taking immunosuppressive medications for transplant avoid probiotic supplements due to the potential risk of infection. However, dysbiosis has also been found in transplant patients, and there is current evidence that Lactobacillus GG and Bifidobacterium can be safe options for transplant recipients.
More studies are needed to determine the best approach for this unique population. However, these new findings are a good reminder that this is an evolving science, and staying current with research is essential for renal dietitians. (11)
Central Venous Catheters (CVC’s)
Several known fungal infections are associated with the Saccharomyces family, a type of yeast that includes S. Boulardii or S. Cerevisiae. These infections are thought to be caused by the translocation of the yeast into the bloodstream. They are most common in patients with CVC’s, primarily those receiving antibiotics and who are critically ill. (12)
In addition, there have been several case reports of spore-forming bacteria like the genus Bacillus causing bloodstream infections in patients with a CVC.
While there are no clear guidelines for the use of spore-forming probiotics or saccharomyces, it’s critical to evaluate the potential risk for patients with CVC’s.
Small intestine bacterial overgrowth (SIBO)
Probiotics were previously thought to be contraindicated for individuals with SIBO. However, a recent meta-analysis by Zhong et al. showed that probiotics decreased abdominal pain and diagnostic markers of SIBO. (13)
In conclusion, However, it is necessary to use even more discernment for patients at a higher risk for infection.
How do probiotic food sources compare to probiotic supplements?
Food sources of probiotics typically contain a much lower amount of CFU’s *colony-forming units of bacteria than probiotic supplements.
Food sources can be an excellent option for individuals who do not tolerate supplemental probiotics or are at high risk for infection.
Some of the best sources of probiotics include:
- Yogurt- always look for live active cultures
- Miso
- Sauerkraut*
- Kimchi
- Tempeh
- Kombucha
- Some pickles
Not all of the foods listed above are good sources of probiotics. We’re all aware that not all yogurts found at grocery stores contain live active cultures, but did you know that sauerkraut may not either!
It’s true! Many sauerkraut products on the market have been pasteurized, destroying the live active cultures. A good rule of thumb to know if sauerkraut is the real deal is to choose refrigerated products.
It’s also good to check the label for pasteurization and vinegar or other preservatives in the ingredients list.
One of the concerns that dietitians may have is the amount of sodium and phosphorus that these fermented foods contain. However, you only need a small amount of these foods to provide a hefty dose of probiotics! Therefore the minimal amounts of sodium and phosphorus far outweigh the risks.
How do we know if probiotic therapy is working?
Although measuring fecal samples before and after introducing probiotic therapy would be fantastic to see what positive changes ensue, unfortunately, this is impossible for many of us.
So how do we know if probiotic therapy is effective and beneficial?
There are several potential markers of success in the effectiveness of probiotics. Closely monitoring for improvements in gastrointestinal symptoms, lab changes, and even quality of life are all telltale signs that probiotics are benefiting our patients. Some of the improved GI symptoms to watch for include:
- Decreased heartburn
- Less constipation or diarrhea
- Improved IBS symptoms
- Less gas or bloating
While there are considerable benefits to utilizing these available therapies, we can’t overshadow the importance of a healthy balanced diet.
Taking a pill or powder cannot undo or improve the effects of a poor diet. Instead, the use of probiotics in addition to a healthy balanced diet full of fiber and prebiotics may result in significant improvements in kidney and gut health in our CKD patients!
Final Thoughts
Dysbiosis is a significant clinical feature of chronic kidney disease.
Research has not yet uncovered therapeutic targets of probiotics to restore the integrity of the microbiome and improve the health of patients with CKD. Still, the evidence so far suggests that it can play a pivotal role in the course and outcomes of the disease.
Probiotic supplements are a tool to consider in treating dysbiosis for individuals with CKD. Research has shown that they can improve inflammatory markers and reduce uremic toxins.
Synbiotic therapy is a combination of pre-and pro-biotics that work synergistically to restore balance in the gut. One well-known product explicitly designed for CKD patients is Renadyl.
Renadyl contains three strains of bacteria that target and metabolize nitrogenous waste products, ideal for uremic patients. It also includes the prebiotic fiber psyllium husk. In patients with stage 3+4 CKD and patients on dialysis, Renadyl shows promising benefits by marked reductions in inflammatory markers and uremic toxins.
Conclusion
As renal dietitians, we are constantly learning about new treatment options for our patients with CKD. Finding new ways to help support kidney and overall health to live long and healthy lives. Reducing the complications of kidney disease is always at the forefront of our care.
Understanding the role of probiotics as a therapeutic approach to kidney care is in its early stages. We are looking forward to learning more from the latest research, our patients, and each other as the science evolves!
Interested in learning more about prebiotics and kidney care? Email to info@kibowbiotech.com
