Epidemiological study on the respiratory pathogens in hospitalized patients with lower respiratory tract infection in Fujian Province

Objective: To detect the probable pathogens in patients with lower respiratory tract infection (LRTI) using a bead-based suspension array, and analyze the epidemiological and clinical characteristics of these patients in Fujian Province. Methods: Sputum and/or bronchoalveolar lavage fluid was collected from 819 hospitalized patients diagnosed with LRTI from the Department of Respiratory Medicine of the four tertiary hospitals in Fujian Province from March 2012 to March 2016. The pathogens were detected using a bead-based suspension array and the data were statistically analyzed in combination with the clinical information. Results: The most common bacteria in LRTI were Pseudomonas aeruginosa (P. aeruginosa), Streptococcus pneumoniae (S. pneumoniae) and Klebsiella pneumoniae (K. pneumoniae); the viruses ranking the top three were influenza a virus (Flu-A), human cytomegalovirus (HCMV), and adenovirus. The analysis of the top three viruses with the highest morbidity revealed that the three most common bacteria in patients with community-acquired pneumonia, acute exacerbation of chronic obstructive pulmonary disease, and bronchiectasis were P. aeruginosa, K. pneumoniae, and S. pneumoniae, while viruses with the largest numbers were Flu-A and HCMV. Due to mixed infection of bacteria and viruses, the patients with LRTI were more likely to suffer from pleural effusion and were prone to have a large patchy shadow. Moreover, leukocyte levels, neutrophil/granulocyte ratio, C-reactive protein, and prognosis including invalid, died rates were all higher compared with the other three groups (P<0.05). Conclusion: The results showed that the study of epidemiological and clinical characteristics in Fujian Province could be used to guide clinical drug use.