[The microbiology of chronic rhinosinusitis with nasal polyps in different phenotype of peripheral blood eosinophils].

Objective

To investigate the association between immune status and microbial community in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) in different phenotype of peripheral blood eosinophils (PBEOS).Method:Retrospective analysis of clinical data of 125 patients with CRSwNP and and 49 control subjects was performed. According to the proportion of peripheral blood eosinophils, the patients with CRSwNP were divided into PBEOS normal group and PBEOS elevated group. The samples of nasal secretions in middle meatus were collected, and then isolated and identified by microbial culture. Differences of microbial colonization rate between the groups were analyzed. SPSS 19.0 software was used to analyze the data.Result:There were 61 cases in PBEOS normal group (0<PBEOS≤ 5%), 64 cases in PBEOS elevated group (PBEOS> 5%) and 49 control subjects.In patient with CRSwNP, the positive rate of microbial culture was 84.4%, and the main microorganisms were Gram positive Aerobic and facultative anaerobic bacteria. The most common bacteria were coagulase negative staphylococci, Staphylococcus epidermidis (S. epidermidis) and Corynebacterium. The average positive rate of Staphylococcus aureus (S.aureus) was 10.4%, and S. epidermidis was 20.0%. The positive rate of S. aureus in the elevated group was higher than that in the normal group (17.2%, 3.3%), and the rate of S. epidermidis was lower (10.9%, 29.5%). The positive rate of S. epidermidis in the elevated group was also lower than that in control subjects (10.9%, 30.6%).

Conclusion

In different PBEOS phenotypes, the colonization rate of S. aureus and S. epidermidis showed the opposite trend. In contrast to the normal goup, the colonization rate of S. aureus in the elevated group increased, and the rate of S. epidermidis decreased. At the same time, the colonization rate of S.epidermidis decreased in elevate group in contrast to the control subjests. This suggests that S. aureus may promote eosinophilic inflammatory response and S. epidermidis may promote noneosinophilic inflammatory response, which plays protective role.