Nasal pathogenic bacteria colonization and related risk factors among medical staff of intensive care unit

Objective To investigate the status and risk factors of nasal pathogenic bacteria colonization among medical staff of intensive care unit (ICU). Methods From February to May 2017, we recruitedthe non-infected ICU medical staff with ≥1 year ICU experience in Qilu Hospital of Shandong University. We collected the general data, blood samples and nasal vestibular swab samples for bacterial culture. Multivariate Logistic regression analysis was used to generate the independent risk factors for the nasal pathogenic bacteria colonization. Results 81 doctors and nurses were enrolled and 50 effective cases were included, 25 cases (50.0%) were identified with nasal pathogenic bacteria colonization. A total of 31 strains were isolated, of which 14 Staphylococcus aureus (45.2%; 2 methicillin-resistant isolates), 5 (16.1%) Enterobacteraerogenes, 4 (12.9%) Klebsiella pneumonia, 4 (12.9%) Citrobacter strains, 2 (6.5%)Klebsiellaoxytoca, 1(3.2%) Enterobacter cloacae, 1 (3.2%) Proteus mirabilis. Compared with those without pathogen colonization, the cases with pathogen colonization had significant shorter working period [(5.1±3.1) years vs (8.4±5.5) years], more frequent nasopharyngeal discomfort (68.0% vs 28.0%), and worse hand hygiene compliance (80.0% vs 28.0%), longer daily bedside contacting time with patients (>4 h) (68.0% vs 28.0%) (all P<0.05). In addition to the above risk factors, the cases colonized with Staphylococcus aureus had significant higher blood neutrophils percentage [(59.5±5.8)% vs (52.7±8.8)%, t=-2.588, P=0.014] and lower lymphocyte percentage [(32.9±5.3)% vs (39.2±7.5)%, t=2.795, P=0.008] (all P<0.05). Multivariate analysis revealed that nasopharyngeal discomfort history (OR=14.223, 95% CI: 1.152-75.575, P=0.038) and bad hand hygiene compliance (OR=13.899, 95% CI: 3.130-61.725, P=0.001) were independent risk factors for nasal pathogenic bacteria colonization (P<0.05). Conclusions It should be noticed thatnear half ICU medical staff had nasal pathogenic bacteria colonization. Improving hand hygiene compliance and early handling of nasopharyngeal symptoms may be beneficial for reducing the nasal colonization rate of pathogens. Key words: Nasal vestibule; Pathogenic bacteria; Colonization; Risk factors