AUTHOR=He Lujuan , Yang Hongzhong , Liu Shenggang , Liang Weijun , Zhou Zezhi , Long Jing , Wu Jinyang 

TITLE=Physiological analysis of severe chlamydia psittaci pneumonia and clinical diagnosis after doxycycline-based treatment

JOURNAL=Frontiers in Physiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2023.1132724

DOI=10.3389/fphys.2023.1132724

ISSN=1664-042X

ABSTRACT=<p><bold>Objective:</bold> To describe the clinical spectrum of severe <italic>Chlamydia psittaci</italic> pneumonia in order to understand the disease better.</p><p><bold>Methods:</bold> Retrospective analysis was made on 31 patients with severe <italic>Chlamydia psittaci</italic> pneumonia diagnosed in ICU by next-generation sequencing of metagenome Metagenomic next-generation sequencing(mNGS) from January 2019–November 2022, including clinical characteristics, laboratory examination results, imaging characteristics, treatment, and prognosis.</p><p><bold>Results:</bold> We included 31 patients with severe <italic>Chlamydia psittaci</italic> pneumonia, 15 of whom had a history of virus exposure. There were 12 cases with multiple bacterial infections, and the common symptoms included fever (31/31,100%), dyspnea (31/31, 100%), cough (22/31, 71.0%), and myalgia (20/31, 64.5%). Laboratory data showed that white blood cells were average or slightly increased, but the levels of C-reactive protein and neutrophils were high. CT findings of the lung were consolidation (19/31, 61.3%) and pleural effusion (11/31, 35.5%). Only one lobe was involved in 11 patients (35.5%). Before diagnosis, 22 patients (71.0%) did not have atypical pathogens in their antimicrobial regimen. After diagnosis, 19 patients (61.3%) received single drug treatment, of which doxycycline or moxifloxacin were the most commonly used drugs. Among 31 patients, three died, nine improved, and nineteen were cured.</p><p><bold>Conclusion:</bold> The clinical manifestations of severe <italic>Chlamydia psittaci</italic> pneumonia are non-specific. The application of mNGS can improve the diagnostic accuracy of <italic>Chlamydia psittaci</italic> pneumonia, reduce the unnecessary use of antibiotics, and shorten the course of the disease. Doxycycline-based treatment is effective for severe <italic>chlamydia psittaci</italic> pneumonia, but it is necessary to understand the secondary bacterial infection and other complications in the course of the disease.</p>