Immune response to Fusobacterium nucleatum, Prevotella intermedia and other anaerobes in children with acute tonsillitis

The number of aerobic and anaerobic bacteria was determined in the saliva of 20 children with acute group A beta-haemolytic streptococcal (GABHS) pharyngo-tonsillitis, and 20 with acute non-GABHS tonsillitis. Antibody titres to four Gram-negative anaerobic bacilli that reside in the oropharynx (Fusobacterium nucleatum, Prevotella intermedia, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans) were determined in these and 20 control patients. An average of 8.8 aerobic and anaerobic isolates per patient saliva specimens were found during the acute tonsillitis stage in both groups, and 6.9 (in GABHS tonsillitis) and 5.6 (in non-GABHS tonsillitis) 5-6 weeks later. There were 10- to 1000-fold more bacteria in the acute stages of the inflammation in both GABHS and non-GABHS groups. These bacteria were Staphylococcus aureus, Haemophilus influenzae, Moraxella catarrhalis, Peptostreptococcus spp., F. nucleatum, Prevotella spp. and Porphyromonas spp. Significantly higher antibodies levels to F. nucleatum and P. intermedia were found in the second serum sample of patients with non-GABHS pharyngo-tonsillitis (P < 0.001) and GABHS tonsillitis (P < 0.05), as compared with their first sample or the levels of antibodies in controls. The increase in the number of several aerobic and anaerobic bacteria during acute tonsillitis and the increase in antibody levels to F. nucleatum and P. intermedia, known oral pathogens, may suggest a possible pathogenic role for these organisms in acute non-GABHS and GABHS tonsillitis.