A good example of the progressive mainstreaming of an alternative medicine into conventional practice is the use of probiotics. Probiotics have long been used by natural medicine practitioners for such afflictions as post-antibiotic vaginosis, diarrhea, irritable bowel, recurrent sinus infections, inflammatory bowel disease, and immune disorders. An excellent recent review article by Kligler and Kligler and Cohrssen 1 demonstrated Category A or B evidenc (SORT evidence rating system) support for probiotics for the following indications:
- Reduce incidence of antibiotic-related diarrhea
- Reduce acute infectious diarrhea
- Reduction in symptoms of IBS
- Prophylaxis for atopic dermatitis in high risk infants
This review article summarizes the strong evidence from meta-analysis and randomized controlled trials that ought change the way physicians practice and prescribe probiotics. They did not go into depth on the many other common uses of probiotics such as lactose intolerance, immunomodulatory effects, vaginal candidiasis, bacterial vaginosis, Helicobacter pylori infections, upper respiratory infections, altered gut permeability (leaky gut), inflammatory disorders, extending remission in pouchitis, reducing incidence of necrotizing enterocolitis in premature infants, and colon cancer prevention. These indications all have been investigated and require more definitive studies to be routinely recommended clinically. However, thoughtful clinicians may consider probiotics in these cases when they see a need and/or failure of conventional therapy.
Let me summarize a case in which probiotics dramatically altered the course of a patient I cared for who had prolonged diarrhea:
A 62 y/o WF with COPD who was treated 3 months prior with antibiotics and steroids for an exacerbation. Developed C. dificile diarrhea and treated with Flagyl. Diarrhea persisted and patient was admitted to hospital with dehydration requiring IV fluids. During a 10 day hospital stay, extensive GI workup was being done to r/o malabsorption, microscopic colitis, sprue, and other causes.WBC of 15,000 spurred use of Levaquin though blood, stool, and urine cultures were all negative. Suspecting gut dysbiosis as the real cause of her diarrhea, antibiotics were stopped and patient placed on 10 Lactobacillus capsules daily from hospital formulary (~250 million CFU each). Within 2 days, diarrhea had resolved and patient was able to stop IV fluids and return home.
In retrospect, after several months of symptoms and extensive workup, the patient had a persistent dysbiosis of her gut flora with a resultant intractable diarrhea. Replacing her gut flora with healthy commensals solved her symptoms in short order.
So perhaps it is best to back up and describe what we mean by probiotics. They are single or mixed cultures of live microbes which have beneficial effects on health by altering the gastrointestinal microflora. They are widely present in fermented food sources such as yogurt, kefir, sauerkraut, milk, some cheeses, miso and tempeh. They are also easily available over the counter in capsule form. In general, products kept in the refrigerated section of a health food store have higher colony counts and quality than those kept dry at room temperature on the drugstore shelf.
The most common organisms in probiotic foods and nutriceuticals preparations are:
- Lactobacillus GG
- Lactobacillus casei
- Lactobacillus acidophilus
- Lactobacillus planatarum
- Lactobacillus reuteri
- Bifidobacterium bifidum/longum
- Saccharomyces boulardii
- Streptococcus thermophilus
All strains are not equivalent for different conditions as in the example of Lactobacillus GG which is more effective than Lactobacillus acidophilus in treating diarrheal diseases.
The mechanisms of action of probiotics include:
- colonization resistance
- production of antibacterial substances
- competition for nutrients
- competitive inhibition at bacterial adhesion sites
- enhancement of the immune defense system
These processes are mediated in part by the formation of biofilms. Bacteria live in single cell or planktonic forms and colonial forms in biofilms, which are highly ordered, often multi-species films exhibiting cooperation and specialization within the film. Components of this probiotic biofilm have anti-infective, anti-adherent qualities, and possibly anti-tumor activity. Probiotics can also inhibit formation of invasive and dysbiotic biofilms. The overall gut microflora is comprised of up to 400 different microbial species, of which 30-40 species predominate and make up 99% of the total bacterial count. Incredibly, the estimated weight of this bacterial biomass is around six pounds, placing it among the body’s largest “organs.” It is not a surprise, therefore, that such a substantial and complex living organism inside our guts can have profound health effects.
How are probiotics prescribed? They should be taken on an empty stomach, spaced 3-4 hours after any antibiotic dosage, continued at least 2 weeks following antibiotic usage. The typical dose should be at least
ranging from 3-30 billion units or even more in difficult cases. They are safe in children in doses of 3-5 billion units daily. The length of intake is uncertain for many conditions. While the refrigerated varieties are most potent, even non-viable organisms may have a benefit such as in blocking bacterial adherence. Dosages of 5-10 billion units have been safely tested in pregnant women and found in high risk cases for familial atopy to reduce atopic eczema in their offspring. Activia, Danactive and Yoplait Yo-Plus are brands containing high counts of probiotic bacteria and may be useful instead of capsule supplements. They also are helpful for those with lactose intolerance, as a calcium supplement, and a delicious source of dairy.
The evidence in this article and suggested by multiple studies is convincing that probiotics are safe, effective, and inexpensive, typically costing under $5 for a short course. Future studies will help clarify clinical recommendations pairing specific conditions and probiotic strain or blends.
for those with lactose intolerance, as a calcium supplement, and a delicious source of dairy. The evidence in this article and suggested by multiple studies is convincing that probiotics are safe, effective, and inexpensive, typically costing under $5 for a short course. Future studies will help clarify clinical recommendations pairing specific conditions and probiotic strain or blends. References: (1) Kligler B, Cohrssen A. Probiotics. Am Fam Phys. 2008;78(9):1073-1078