title: Clinical evaluation of the oral probiotic Streptococcus salivarius K12 in the prevention of recurrent pharyngitis and/or tonsillitis caused by Streptococcus pyogenes in adults.
abstract: BACKGROUND
  Streptococcus salivarius K12 has been shown to inhibit the growth of Streptococcus pyogenes due to bacteriocins release. Because of its ability to colonize the oral cavity, we have tested the strain K12 for its efficacy in preventing streptococcal pharyngitis and/or tonsillitis in adults.
  
  
  METHODS
  Forty adults with a diagnosis of recurrent oral streptococcal pharyngitis were enrolled in the study. Twenty of these subjects took for 90 days a tablet containing Streptococcus salivarius K12 (Bactoblis®). The other 20 subjects served as untreated controls. A 6-month follow-up was included to evaluate any persistent protective role.
  
  
  RESULTS
  The 20 adults who completed the 90-day course of Bactoblis® showed a reduction in their episodes of streptococcal pharyngeal infection (about 80%). The 90 days treatment was also associated with an approximately 60% reduction in the incidence of reported pharyngitis in the 6-month period following use of the product. The product was well tolerated by the subjects with no treatment-related side effects or drop-outs reported.
  
  
  CONCLUSIONS
  Prophylactic administration of Streptococcus salivarius K12 to adults having a history of recurrent oral streptococcal pathology reduced the number of episodes of streptococcal pharyngeal infections and/or tonsillitis.
authors.affiliation: Velleja Research, Scientific Department, Viale Lunigiana 23, 20125, Milano, Italy. f.dipierro@vellejaresearch.com
authors.forename: Francesco
authors.initials: F
authors.lastname: Di Pierro
authors.forename: Teresa
authors.initials: T
authors.lastname: Adami
authors.forename: Giuliana
authors.initials: G
authors.lastname: Rapacioli
authors.forename: Nadia
authors.initials: N
authors.lastname: Giardini
authors.forename: Christian
authors.initials: C
authors.lastname: Streitberger
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010612:Pharyngitis / Q000382:microbiology / Q000517:prevention & control*; D019936:Probiotics / Q000008:administration & dosage*; D012008:Recurrence; D013290:Streptococcal Infections / Q000382:microbiology / Q000517:prevention & control*; D013291:Streptococcus / Q000502:physiology*; D013297:Streptococcus pyogenes / Q000472:pathogenicity*; D014069:Tonsillitis / Q000382:microbiology / Q000517:prevention & control*; D055815:Young Adult