The publications and other materials used herein to illuminate the background of the invention, and in particular, cases to provide additional details respecting the practice, are incorporated by reference.
Xylitol has been classified as a polyol or a sugar alcohol and is referred to as birch sugar, because it can be produced from birch. Xylitol occurs widely in nature, although the concentrations are low. Natural sources of xylitol include plums, strawberries, rasberries and rowan berries (1). Xylitol has the same relative sweetness as sucrose, and it has been used as a sugar substitute for dietary and medical purposes. Because of its five-carbon sugar alcohol structure, xylitol is unsuitable as a source of energy for most oral micro-organisms, such as Streptococcus mutans (2). Yet, most S. mutans strains are, via the fructose phosphotransferase system, able to transport xylitol into the cell, where it is phosphorylated into xylitol-5-phosphate, which then has to be expelled from the cell (3). This metabolically futile xylitol cycle consumes energy stores of the call and is thought to be responsible for the inhibition of the growth of S. mutans observed both in vitro and in vivo when exposed to xylito (4).
Regular consumption of xylitol has been shown to reduce the incidence of dental caries, although the mechanisms are not completely understood (5-8). The most significant effect so far demonstrated is the ability of xylitol to reduce the growth and acid production of S. mutans, which is the most important bacterium taking part in the pathomechanism of dental caries (9).
We have previously found that xylitol inhibits the growth of S. pneumoniae and S. mutans in vitro during their logarithmic growth phase. This effect is dosedependent. We similary observed a slight postexponential inhibition of growth with beta-hemolytic streptococci, but not with Haemophilus influenzae, nor with Moraxella catarrhalis (10). The disclosure of this reference 10 is hereby incorporated as reference.
S. pneumoniae is an important etiologic agent of bacterial pneumonia, sepsis and meningitis (11). It accounts for about 30% of all acute otitis media (AOM) episodes, as estimated by bacterial cultures from the middle-ear (12-13). This figure may be even higher when more sensitive methods of detecting bacteria are applied (14). At the age of 3 years, 20 to 40% of healthy children carry pneumococci in their nasopharynx. This carriage increases during acute infections (15). Nasopharyngeal carriage of pneumococci has been shown to be a predisposing factor for AOM in children in the day care setting (15).