Omadacycline for pulmonary coinfection with chlamydia psittaci and staphylococcus aureus:A case report
Zhou Guoqiong
Liu Jilou
Zhang Ming
Abstract：Objective:To report the diagnosis and treatment of a case of pneumonia caused by coinfection with Chlamydia psittaci and Staphylococcus aureus,highlighting the clinical significance of atypical pathogen infections.Methods:A 28-year-old woman presented with pharyngalgia,dry cough,and high fever.Chest CT revealed patchy consolidation in the right lower lobe,and laboratory tests indicated elevated inflammatory markers,leading to an initial diagnosis of community-acquired pneumonia(CAP).After 2 days of moxifloxacin treatment with no significant improvement and worsening headache,further history-taking revealed bird exposure and her pet parrot's diarrhea history,suggesting psittacosis.Intravenous omadacycline tosylate(100 mg once daily)was initiated.Symptoms improved within 3 days,and bronchoscopy with metagenomic next-generation sequencing(mNGS)of bronchoalveolar lavage fluid confirmed C.psittaci and S.aureus coinfection.Results:Follow-up CT at day 12 showed continued radiographic improvement.The patient was discharged on oral doxycycline for 1 month,with near-complete resolution on final CT.Conclusions:C.psittaci and S.aureus coinfection is rare in CAP.Avian exposure history warrants clinical suspicion.Timely antibiotic adjustment and advanced diagnostics like mNGS enhance diagnostic accuracy and therapeutic precision,improving outcomes.
Keywords：Chlamydia psittaci pneumoniaStaphylococcus aureusOmadacyclineMetagenomic next-generation sequencing
Publication Date：2025-06-28
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：3( 207-209 )