Research offers promising evidence that probiotics might help to treat childhood respiratory infections, genitourinary infections, as well as atopic dermatitis and allergic diseases.
Based on this clinical evidence, the American Academy of Family Physicians gives the following key recommendations for practice regarding probiotic use:
- Probiotics may reduce the incidence of antibiotic-related diarrhea.
- Probiotics may reduce the duration and severity of all-cause infectious diarrhea.
- Probiotics may reduce the severity of pain and bloating in patients with irritable bowel syndrome.
- Probiotics may reduce the incidence of atopic dermatitis in at-risk infants. There is preliminary support for treatment of symptoms (AAFP 2008)
Probiotic therapy as a treatment for atopic dermatitis has been escalating in recent years. Indeed, considering the increasing prevalence of eczema and the lack of a definitive cure, patients and parents often turn to complementary and alternative medicine treatments when they are dissatisfied with the result of conventional medicine [Astin 1998].
In addition, atopic dermatitis is often associated with other allergic diseases, including food allergies, asthma and seasonal allergies, and some experts advocate the “atopic march” theory, which suggests that atopic dermatitis may lead to subsequent allergic conditions such as those of the respiratory and gastrointestinal systems. Therefore, there is significant interest in the prevention of atopic dermatitis to possibly halt the development of other allergic illnesses [Spergel 2010].
Given that the bacterial flora is very different in patients with atopic dermatitis, the idea that adding back healthy bacteria might be a useful treatment is compelling. An exciting paper in 2001 showed that the probiotic strain Lactobacillus rhamnosus GG reduced the incidence of atopic dermatitis in at-risk infants through the age of 7 years [Alliomaki 2001].
In 2005, a similarly exciting paper seemed to take this a step farther, showing that probiotics given twice daily to children with moderate to severe AD led to significant improvements over the use of a placebo [Weston 2005].
At that time there was a lot of initial excitement about the positive role of probiotics in eczema prevention and treatment. Then in 2008, a study found no reduction in incidence or severity of atopic dermatitis with probiotic supplementation, and it even found an association between such supplementation and increased incidence of wheezing bronchitis [Kopp 2008]. In this study, however, only breastfeeding mothers were supplemented with the Lactobacillus rhamnosus GG strain of probiotics during the first three months after birth.
In the studies that followed, researchers experimented with different strains of probiotics, dosing, timing, and frequency in order to optimize the efficacy of probiotics and achieve more consistent results. In 2009, in the first study of its kind, the Probiotics and Allergy (PandA) trial selected strains of probiotics based on their anti-inflammatory activity [Niers 2009].
Trial participants received either a multistrain probiotic supplement (Bifidobacterium bifidum, Bifidobacterium lactis, and Lactococcus lactis) or a placebo administered prenatally (6 to 8 weeks prior to delivery) and postnatally (infants were supplemented for 12 months).
Fecal colonization with Bifidobacterium was confirmed in 100 percent of the probiotic group at three months of age, while only 85 percent of the control group showed such colonization. A larger proportion of the probiotic group also demonstrated colonization with Lactococcus lactis. Blood analysis to measure the levels of inflammatory markers revealed lower levels in the probiotic group, suggesting some anti-inflammatory effect.
The physician-reported incidence of eczema in the trial was 23 percent in the control group and 6 percent in the probiotic group, which was significant. The results also showed a long-term reduction in the incidence of eczema measured at 2 years of age.
Supporting this work, a meta-analysis of 14 trials demonstrated that probiotics decreased the incidence of atopic dermatitis, regardless of prenatal or postnatal use or the subjects receiving the probiotics (mother or child) [Pelucchi 2012]. Additionally, in a 2012 review, a significant risk reduction was found for AD in children 2 to 7 years old after the administration of Lactobacilli strains of probiotics during pregnancy [Doege 2012].
A very recent study on probiotics and AD prevention, published October 2012 in The Journal of Allergy and Clinical Immunology, found that supplementation with strains of Lactobacillus rhamnosus and Bifidobacterium longum or Lactobacillus paracasei and Bifidobacterium longum in combination reduced the risk of developing eczema in infants [Rautava 2012]. In this study of 241 mother-infant pairs, breastfeeding mothers were supplemented with probiotics beginning 2 months before delivery and during the first 2 months of breast feeding. Reduction in eczema development in high-risk infants was confirmed up to 2 years of age.
credit to: nationaleczema.org