Dr. Seema Alam *
Reader, Dept of Pediatrics, JN Medical College, AMU, Aligarh 202001, UP *
|Probiotic is a live microbial culture food ingredient which beneficially influences the health and nutrition of the host. The term prebiotic was introduced by Gibson and Roberfroid who exchanged "pro" for "pre", which means "before" or "for". They defined prebiotics as "a non-digestible food ingredient that beneficially affects the host by selectively stimulating the growth and/or one or a limited number of bacteria in the colon."
The term symbiotic is used when a product contains both probiotics and prebiotics. Because the word alludes to synergism, this term should be reserved for products in which the prebiotic compound selectively favors the probiotic compound.
An analysis of physician practices in a small Canadian city showed that only 31% had any knowledge of probiotics and 24% felt that probiotics had no place in their practices. The 31% figure may be much higher in many parts of the Western world, and of those who have knowledge, the accuracy of their information may also be flawed.
The comprehensive review of the literature by the expert panel of FAO and WHO demonstrated a relatively small number of areas in which probiotics have proven anti-disease effects.
Bacterial colonization or infection of the intestine by pathogens such as Clostridium, Escherichia, Klebsiella, Salmonella, Shigella, Campylobacter, Pseudomonas, Streptococcus, Enterococcus, Staphylococcus aureus , and coagulase-negative staphylococci increases the risk of necrotizing enterocolitis. If non pathogens, such as lactobacilli and bifidobacteria, colonize the intestine, or if breast milk rather than formula is used, the incidence of necrotizing enterocolitis has been reported to fall.
A study of the enteric microbiota of 25 babies with necrotizing enterocolitis compared to 23 matched controls revealed that lactobacilli were less common in the necrotizing enterocolitis babies (12% versus 48%, P = 0.006). Perhaps the most impressive indication that probiotics could benefit newborns comes from a human trial with 2.5 x 10 8 live Lactobacillus acidophilus and 2.5 x 10 8 live Bifidobacterium infantis in 1,237 neonates in Colombia . Compared with 1,282 hospitalized patients seen during the previous year, treatment with these strains resulted in a 60% reduction in necrotizing enterocolitis and overall mortality. This has been mirrored in a more cent clinical trial done on Chinese VLBW babies.
A subsequent study involved newborn infants with a gestational age of less than 33 weeks or birth weight of less than 1,500 g and a standard milk feed supplemented with Lactobacillus GC once a day until discharge, found a reduced rate of necrotizing enterocolitis compared to placebo (1.4% versus 2.7%) but was not statistically significant, suggesting that either the GG strain is not as good as the L.acidophilus-B infantis combination, milk is not an effective delivery system, or probiotics are not as effective as earlier thought. We have no such studies from India.
The strongest evidence of a beneficial effect of probiotics in acute diarrhea (more so rotavirus diarrhea) has been established in the western literature with LGG by at least three meta-analyses. But recently published 2 studies from Brazil and Peru have found no effect of the LGG. There is some evidence that Saccharomyces boulardii is more effective against bacterial diarrhea. In our own country there is scarcity of published evidence. In a RCT done at our center (with tyndallized Lactobacillus acidophilus) we found no beneficial effect of the probiotic. With the etiological profile of diarrhea so different in the developing world, I think we need more studies to decide the issue. Till then we should not encourage probiotics as they tend to increase the management cost of acute diarrhea.
There is enough evidence for the role of probiotics in antibiotic associated diarrhea but the prevalence of antibiotic associated diarrhea in our setting of pediatric patients is very low. So how justified are the probiotic antibiotic combinations swarming the Indian markets?
Recently there is a lot of interest generated for the role of probiotics in IBD especially in Crohn's disease. One such open label study done in pediatric age group did show beneficial effect of Lactobacillus GG but double blind placebo controlled RCT's are warranted for establishing the role.
There are some in vitro and animal data to indicate that lactic acid bacteria can inhibit the H. pylori's growth and decrease the urease enzyme activity, necessary for it to survive in the acidic environment of the stomach. In humans, there is also evidence that probiotic strains can suppress infection and lower the risk of recurrences. Much more data is required before we can decide the role of probiotics in treatment of H.pylori.
In my opinion we, as health care givers in a poor nation like India , should feel the responsibility of not allowing any treatment modalities to be forced on us (by business pressures or doctored trials) unless proved by scientifically planned trials in our own country.
|How to Cite URL :|
|Alam S D.. Available From : http://www.pediatriconcall.com/fordoctor/ Conference_abstracts/report.aspx?reportid=203|