Dynamics of nasopharyngitis in children.

Abstract

Our goal was to characterize the dynamics and bacterial interaction of the aerobic and anaerobic flora of nasal discharge of children at different stages of uncomplicated nasopharyngitis. Serial semiquantitative nasopharyngeal (NP) and quantitative nasal discharge (ND) cultures were taken every 3 to 5 days from 20 children in whom purulent discharge eventually developed (group 1), and a single culture was obtained from a group of 20 who had only clear discharge (group 2). Aerobic and anaerobic bacteria were isolated from all NP cultures. Bacterial growth was present in 8 (40%) NDs of group 2. Only 7 (35%) of the clear NDs of group 1 showed bacterial growth; the number increased to 14 (70%) at the mucoid stage and 20 (100%) at the purulent stage. It declined to 6 (30%) at the final clear stage. The number of species and total number of organisms increased in the NDs of group 1. Group 1 patients had higher recovery rates of Streptococcus pneumoniae and Haemophilus influenzae in their NP cultures than group 2 patients (P < 0.05). During the purulent stage, Peptostreptococcus species were isolated in 15 (75%), Fusobacterium species in 10 (50%), Prevotella species in 9 (45%), H influenzae in 8 (40%), S pneumoniae in 6 (30%), and beta-hemolytic streptococci in 5 (25%) of group 1 NDs. This was higher than their recovery in the clear stages of both groups and the mucoid stage of group 1. A total of 8 organisms capable of interfering with the growth of potential pathogens were isolated from the NPs of group 1, as compared with 35 from group 2 (P < 0.001). The development of purulent nasopharyngitis is associated with the pre-existing presence of potential pathogens and the absence of interfering organisms.