Table 2

 Focal manifestations of infection, age dependence and involved bacterial groups

Age (years)<22–<44–<1515–<25⩾25
A, adenoids; T, tonsils
Number of patients1020201010
Number of samples1010202020101010
No signs of infection11254814
Adherent infiltrates
    No adherence (single bacteria irregularly attached to the epithelium)5812164915
    Adherence exclusively to crypt entrance and within crypts00001124
    Islands of adherence covering <5% of the epithelial surface426410441
    Lawns of bacteria covering >5% of the epithelial surface10205130
    No fissures5781557710
    Branched fissures00004100
    Diffuse infiltration of tissue761276300
Occurrence of bacterial groups
    Haemophilus influenzae (Haeinf)761469220
    Beta-Proteobacteria incl. Neisseria (Bet42a)20203012
    Actinobacteria (HGC)65936402
    Atopobium and other (Ato291)00102010
    Coriobacterium group (Cor653)00002011
    Firmicutes (LGC)3311813743
    Fusobacteria (Fuso)00524110
    Streptococcus (Strc493)428713567
    Streptococcus pyogenes (Strpyo)10003022
    Staphylococcus aureus (Staaur)31000023
    Lactobacillus and Enterococcus (Lab)30427001
    Clostridium coccoides—Eubacterium rectale group (EREC)20525021
    Listeria, Brochothrix (Lis 637,1255)00001021
    Ruminococcus bromii, Ruminococcus flavefaciens (Rbro, Rfla)00113000
    Veillonella group incl. Veillonella parvula (Veil,Vepa)10215043
    Bacteroides/Prevotella group (Bac303)42724143
    Cytophaga-Flavobacteria (CF 319)21218344
    Prevotella intermedia (Prin)10412000
    Burkholderia (Burcep, Burkho)00534201
    Pseudomonas (Ps, Pseaer A, Pseaer B)21554034