Terhi Tapiainen

Xylitol in preventing acute otitis media.

Xylitol is a polyol sugar alcohol and is referred to as birch sugar, because it can be produced from birch. Natural sources of xylitol include plums, strawberries, raspberries and rowan berries. Xylitol inhibits the growth of Streptococcus pneumoniae and it inhibits the attachment of both pneumococci and Haemophilus influenzae on the nasopharyngeal cells. In two clinical trials xylitol was found efficient to prevent the development of acute otitis media with a daily dose of 8.4-10 g of xylitol given in five divided doses. The efficacy in these 2-3 months follow-up trials was approximately 40% when chewing gum was used and approximately 30% with xylitol syrup. The need to use antimicrobials reduced markedly when using xylitol. In a high-risk group of children with tympanostomy tubes xylitol was ineffective in preventing otitis. Xylitol appears to be an attractive alternative to prevent acute otitis media. A more practical frequency of doses should be found before its use can be widely recommended.

Childhood Urinary Tract Infections as a Cause of Chronic Kidney Disease

OBJECTIVE: Urinary tract infections (UTIs) in childhood are considered a risk for chronic kidney disease (CKD), but this association is poorly verified. We wanted to determine the etiologic fraction of UTIs in childhood as a cause of CKD. METHODS: A systematic literature search on the association between childhood UTIs and CKD was conducted, and data for patients with CKD in the area of 1 tertiary care hospital were reviewed. RESULTS: In our literature search, we found no patients among the 1576 reviewed cases for whom childhood UTIs were the main cause of subsequent CKD. However, there were 3 patients with childhood UTIs for whom the results of kidney imaging studies were not reported. Of the 366 patients with CKD who were monitored in the Oulu University Hospital, 308 had a specific noninfectious cause of CKD. Of the remaining 58 patients, 13 had a history of UTIs in childhood. In their first imaging studies, all of those 13 patients demonstrated kidney tissue abnormalities, which could have been observed through ultrasonography. Recurrent UTIs in childhood were possibly the cause of CKD in 1 case; therefore, the etiologic fraction of recurrent childhood UTIs as a main cause of CKD was, at most, 0.3%. CONCLUSIONS: In the absence of structural kidney abnormalities evident in imaging studies after the first childhood UTI, the etiologic fraction of recurrent childhood UTIs as a main cause of CKD seems to be small. A child with normal kidneys is not at significant risk of developing CKD because of UTIs.

Effect of Xylitol on Growth of Streptococcus pneumoniae in the Presence of Fructose and Sorbitol

ABSTRACT Xylitol is effective in preventing acute otitis media by inhibiting the growth of Streptococcus pneumoniae. To clarify this inhibition we used fructose, which is known to block similar growth inhibition observed in Streptococcus mutans. In addition, we evaluated the efficacy of sorbitol in inhibiting the growth of pneumococci, as sorbitol is widely used for indications similar to those for which xylitol is used. The addition of 5% xylitol to the growth medium resulted in marked growth inhibition, an effect which was totally eliminated in the presence of 1, 2.5, or 5% fructose but not in the presence of 1 or 5% glucose, 1% galactose, or 1% sucrose. This finding implies that xylitol-induced inhibition of pneumococcal growth is mediated via the fructose phosphotransferase system in a way similar to that in which mutans group streptococcal growth is inhibited. The addition of sorbitol at concentrations of 1, 2.5, or 5% to the growth medium did not affect the growth of pneumococci and neither inhibited nor enhanced the xylitol-induced growth impairment. Thus, it seems that xylitol is the only commercially used sugar substitute proven to have an antimicrobial effect on pneumococci.

Failure of Xylitol Given Three Times a Day for Preventing Acute Otitis Media

Background: Xylitol administered regularly 5 times a day after each meal is successful in preventing acute otitis media (AOM) in children, but if given only during respiratory infections it is ineffective against AOM. To find a more convenient dosing regimen, we tested whether xylitol administered 3 times a day reduces the occurrence of AOM. Methods: In this 3-month randomized, double-blind trial, 663 healthy day care children were randomized to receive either a control product (n = 331) or xylitol (n = 332). Xylitol was given in chewing gum or in a mixture 3 times a day, the daily dose being 0.5 g in the control group and 9.6 g in the xylitol group. The occurrence of the first AOM diagnosed during any period of respiratory symptoms during the follow-up was the main outcome measure. Results: At least one AOM episode was diagnosed in 98 of the 331 children who received control products (30%) and in 94 of the 332 who received xylitol products (28%). A total of 142 episodes of AOM were diagnosed in the control group compared with 156 in the xylitol group. The differences were not statistically significant. Conclusions: Xylitol given regularly 3 times a day for 3 months during the respiratory infection season failed to prevent AOM.

Dynamics of gut colonization and source of intestinal flora in healthy newborn infants

The aim of the study was to evaluate the dynamics of gut colonization and the main source of intestinal bacterial flora in infancy in a quantitative manner using computerized analysis of bacterial cellular fatty acid (CFA) profiles. Each stool was collected from 10 healthy newborn infants during their first 2–7 days of life and a follow‐up sample at 6 months of age. Stool samples were collected from mothers and nurses for comparison. Gas‐liquid chromatography of the 159 stool samples was used to produce bacterial cellular fatty acid (CFA) profiles by means of a previously developed computerized program. The CFA profiles for the infants fluctuated from hour to hour during the first days of life and resembled those for both the mothers and the nurses, doing so all the more in the case of the five infants examined 6 months after birth. Gut colonization fluctuated markedly from hour to hour in the perinatal period. The effect of the maternal flora on the initial gut colonization may be less than expected as the fecal flora of infants started to resemble both the fecal flora of the mother as well as that of the first nurse.

Effect of xylitol and other carbon sources on Streptococcus pneumoniae biofilm formation and gene expression in vitro

Kurola P, Tapiainen T, Sevander J, Kaijalainen T, Leinonen M, Uhari M, Saukkoriipi A. Effect of xylitol and other carbon sources on Streptococcus pneumoniae biofilm formation and gene expression in vitro. APMIS 2010; 119: 135–42.

Biofilm formation by Streptococcus pneumoniae isolates from paediatric patients

Tapiainen T, Kujala T, Kaijalainen T, Ikäheimo I, Saukkoriipi A, Renko M, Salo J, Leinonen M, Uhari M. Biofilm formation by Streptococcus pneumoniae isolates from paediatric patients. APMIS 2010; 118: 255–60.

Effect of antimicrobial treatment of acute otitis media on the daily disappearance of middle ear effusion: a placebo-controlled trial.

IMPORTANCE Antimicrobial treatment reduces the symptoms of acute otitis media (AOM). The effect of antimicrobial treatment on the duration of middle ear effusion (MEE) and concomitant hearing impairment is not known. OBJECTIVE To determine whether the antimicrobial treatment of AOM reduces the duration of MEE. DESIGN, SETTING, AND PARTICIPANTS This randomized, double-blind, placebo-controlled trial involved a total of 84 children with AOM between 6 months and 15 years of age. Participants were recruited from September 14, 1999, to January 4, 2000; October 10, 2005, to December 16, 2005; and September 22, 2009, to June 4, 2012, from among children attending an AOM prevention trial and children visiting local outpatient clinics in Oulu, Finland. INTERVENTIONS Children were randomly allocated to receive either 40 mg/kg of amoxicillin-clavulanate or a placebo mixture per day for 7 days. MAIN OUTCOMES AND MEASURES The primary outcome measure was the time to the disappearance of MEE as defined by a normal tympanogram finding (A curve) from both ears on 2 consecutive measurement days. Parents performed daily tympanometry at home. The study physician performed tympanometry and otoscopy at study entry, after 3 and 7 days, and then weekly until both ears were healthy. The main secondary outcome measures were the time to normal otoscopy findings and the proportion of children without persistent MEE at 14 days and 2 months. RESULTS Middle ear effusion disappeared 2.0 weeks (13.7 days) earlier (P = .02) in the antimicrobial group (mean time, 2.7 weeks; 95% CI, 1.7-3.7) than in the placebo group (4.7 weeks; 95% CI, 3.6-5.7). Normal otoscopy findings were observed 1.4 weeks sooner in the antimicrobial group than in the placebo group (P = .02). On day 14, 69% of children in the antimicrobial group and 38% in the placebo group had normal tympanometry findings (number needed to treat, 3.2; 95% CI, 2.0-10.5). On day 60, 2 children (5%) in the antimicrobial group and 10 children (24%) in the placebo group had persistent MEE (P = .01). CONCLUSIONS AND RELEVANCE Antimicrobial treatment effectively reduced the duration of MEE and possible concomitant hearing impairment in children with AOM. Antimicrobial treatment also reduced the risk for persistent MEE. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01244581.

Xylitol Concentrations in the Saliva of Children After Chewing Xylitol Gum or Consuming a Xylitol Mixture

Abstract.Xylitol prevents otitis media when given to children regularly five times per day. To find a more convenient dosing schedule, an enzymatic assay was used to measure xylitol concentrations in the saliva of 65 children after giving them xylitol chewing gum or syrup in doses equal to those used in clinical trials. Although concentrations high enough to have an antimicrobial effect were attained, the xylitol disappeared from the saliva within 15 min. This finding indicates that high peak concentrations are more important for efficacy than the amount of time the xylitol concentration exceeds that needed to produce an antimicrobial effect. A schedule with the same single doses given less frequently could be clinically effective in preventing otitis media.

Finnish guidelines for the treatment of laryngitis, wheezing bronchitis and bronchiolitis in children.

Evidence‐based guidelines are needed to harmonise and improve the diagnostics and treatment of childrens lower respiratory tract infections. Following a professional literature search, an interdisciplinary working group evaluated and graded the available evidence and constructed guidelines for treating laryngitis, bronchitis, wheezing bronchitis and bronchiolitis.