Prebiotics in infants for prevention of allergic disease and food hypersensitivity.

BACKGROUND: The composition of the intestinal microflora may be different in individuals with atopic eczema from those without this condition, and such differences may precede the development of eczema. Prebiotics are nondigestible food components that benefit the host by selectively stimulating the growth or activity of non-pathogenic bacteria in the colon. Prebiotics (commonly oligosaccharides) added to infant feeds have the potential to prevent sensitisation of infants to dietary allergens. OBJECTIVES: To determine the effect of prebiotics given to infants for the prevention of allergic disease or food hypersensitivity. SEARCH STRATEGY: This included searches of the Cochrane Central Register of Controlled Trials (Issue 1, 2007), MEDLINE (1966 - February 2007), EMBASE, PREMEDLINE, abstracts of conference proceedings and citations of published articles, and expert informants. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials that compared the use of a prebiotic to no prebiotic; or the use a specific prebiotic compared to a different prebiotic. DATA COLLECTION AND ANALYSIS: Assessment of trial quality, data extraction and synthesis of data were performed using standard methods of the Cochrane Neonatal Review Group. MAIN RESULTS: Seven studies were eligible for inclusion. Only two studies reported an allergic disease outcome for 432 infants. Study quality was reasonable, although Moro 2006 reported 20% post-randomisation losses. Moro 2006 enrolled hydrolysed formula fed infants at high risk of allergy and reported a significant reduction in eczema in infants up to six months of age (RR 0.42, 95% CI 0.21, 0.84). Ziegler 2007 enrolled formula fed infants who were not selected on the basis of risk for allergy and reported no significant difference in eczema up to four months of age (RR 1.62, 95% CI 0.62, 4.26). Meta-analysis of the two studies found no significant difference in eczema, but significant heterogeneity was detected. Differences were potentially attributable to differences in infant risk, prebiotic formulation or measurement of eczema. Analysis of five studies reporting measures of infant growth found no consistent adverse effects. AUTHORS' CONCLUSIONS: There is insufficient evidence to determine the role of prebiotic supplementation of infant formula for prevention of allergic disease and food hypersensitivity. One small trial of prebiotic oligosaccharides with excess losses reported a reduction in eczema in high risk formula fed infants. Further trials are needed to determine whether this finding persists over a longer period of time, applies to other manifestations of allergic disease, is associated with reductions in allergen sensitisation, and is reproducible.

Probiotics in infants for prevention of allergic disease and food hypersensitivity.

BACKGROUND: The composition of the intestinal microflora may be different in individuals with atopic eczema from those without this condition, and such differences may precede the development of eczema. Probiotics are live bacteria that colonize the gastrointestinal tract and provide a health benefit to the host. Probiotics added to infant feeds have the potential to prevent sensitisation of infants to dietary allergens. OBJECTIVES: To determine the effect of probiotics given to infants for the prevention of allergic disease or food hypersensitivity. SEARCH STRATEGY: This included searches of the Cochrane Central Register of Controlled Trials (Issue 1, 2007), MEDLINE (1966 - February 2007), EMBASE, PREMEDLINE, abstracts of conference proceedings and citations of published articles, and expert informants. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials that compare the use of a probiotic to no probiotic; or the use a specific probiotic compared to a different probiotic; or a probiotic with added prebiotic to control. DATA COLLECTION AND ANALYSIS: Assessment of trial quality, data extraction and synthesis of data were performed using standard methods of the Cochrane Neonatal Review Group. MAIN RESULTS: Twelve studies were eligible for inclusion. Allergic disease and / or food hypersensitivity outcomes were assessed by 6 studies enrolling 2080 infants, but outcomes for only 1549 infants were reported. Studies generally had adequate randomisation, allocation concealment and blinding of treatment. However, the findings of this review should be treated with caution due to excess losses in patient follow-up (17% to 61%). Meta-analysis of five studies reporting the outcomes of 1477 infants found a significant reduction in infant eczema (typical RR 0.82, 95% CI 0.70, 0.95). However, there was significant and substantial heterogeneity between studies. One study reported that the difference in eczema between groups persisted to 4 years age. When the analysis was restricted to studies reporting atopic eczema (confirmed by skin prick test or specific IgE), the findings were no longer significant (typical RR 0.80, 95% CI 0.62, 1.02). All studies reporting significant benefits used probiotic supplements containing L. rhamnosus and enrolled infants at high risk of allergy. No other benefits were reported for any other allergic disease or food hypersensitivity outcome. AUTHORS' CONCLUSIONS: There is insufficient evidence to recommend the addition of probiotics to infant feeds for prevention of allergic disease or food hypersensitivity. Although there was a reduction in clinical eczema in infants, this effect was not consistent between studies and caution is advised in view of methodological concerns regarding included studies. Further studies are required to determine whether the findings are reproducible.

Developmental outcome of preterm infants after surfactant therapy: systematic review of randomized controlled trials.

OBJECTIVES: To review neuro-developmental outcome at 1 and 2 years of age following randomized controlled trials (RCT) of neonatal surfactant therapy. METHODS: A systematic review of the MEDLINE, Embase and Cochrane Controlled Trial Register databases, searching for RCT of surfactant replacement therapy with follow-up outcomes, was carried out. The main outcome measures were severe and mild disability at 1 and 2 years plus composite adverse outcome of death and/or severe disability. RESULTS: A meta-analysis using odds ratios was carried out on 13 RCT. There were a total of 2218 treated and 2090 control infants who underwent follow up at 1 year of age. There were 303 treated and 292 control infants with follow up at between 18 months and 2 years of age. Surfactant therapy was associated with a lower rate of mild disability at 1 year (OR 0.79; 95% CI 0.66-0.95). There was a reduction in the combined adverse outcome (death or severe disability rate) at 1 year (OR 0.8; 95% CI 0.72-0.89). Neither the 1 year nor the 2 year follow-up examination showed a statistical difference in the severe disability rate between the control and treated group. CONCLUSION: Surfactant therapy increases survival without an increase in subsequent morbidity at 1 and 2 years of age.

Umbilical cord blood lactate in normal infants: comparison between two methods of measurement.

OBJECTIVES: Firstly, to determine the accuracy of the Radiometer ABL 625 lactate electrode (Radiometer Medical Pty Ltd, Nunawading, Victoria, Australia) by comparing the lactate values obtained by this method to those obtained with the Hitachi 917 lactate analyser (Boehringer Mannheim Corporation, Charlottetown, Prince Edward Island, Canada). Secondly, to determine the effect of delay in measurement on blood lactate levels. METHODOLOGY: Umbilical venous (UCV) blood samples were obtained from healthy term infants delivered vaginally. Lactate levels were measured with the Radiometer ABL 625 lactate electrode in the Neonatal Intensive Care Unit, Westmead Hospital and with the Hitachi 917 lactate analyser in 49 paired samples. In addition 26 UCV blood samples were placed in ice slurry and a further 26 samples at room temperature and blood lactate was measured at 5-min intervals for 30 min to determine the change of lactate levels with time. RESULTS: The lactate levels obtained from the Radiometer ABL 625 lactate electrode were consistently lower than the levels obtained from the Hitachi 917 lactate analyser (mean difference - 0.24), but the correlation was high (r = 0.97). The blood lactate levels increased at the rate of 0.012 mmol/L per min if the blood was left at room temperature. The lactate levels remained stable for 20 min if the blood was placed in ice slurry. CONCLUSION: The Radiometer ABL 625 lactate electrode was easy to use and there was high correlation with the values obtained by the standard laboratory method. The blood specimen must be place in an ice slurry if a delay in analysis is anticipated.