Successful Treatment of Severe Community-Acquired Pneumonia caused by Chlamydia Psittaci: a Case Report

Community acquired pneumonia is a common and deadly condition, which remains a major cause of morbidity and mortality throughout the world. Chlamydia psittaci pneumonia is responsible for less than 5% of community-acquired pneumonia with a fatality rate of 1%. Nonetheless, it is underestimated due to low awareness of the disease and atypical clinical presentation in a majority of the cases. Metagenomic next-generation sequencing can help us diagnose and clarify the etiology in time.We reported a case of an 85-year-old man who presented with intermittent fever and cough with wheezing for 4 days and did a review of related literature.The patient was admitted to our department due to severe CAP and multiple organ dysfunction. After admission, we applied an empirical antibiotic strategy, performed intubation and invasive ventilation, fluid resuscitation, vasoactive drugs and supportive care. On the third day of admission, metagenomic next-generation sequencing results of blood and bronchoalveolar lavage fluid suggested Chlamydia psittaci. We made a diagnosis of sever Chlamydia psittaci pneumonia and adjusted antibiotics to minocycline combined with azithromycin two days after admission. The patient was successfully cured with a good prognosis.Detecting the pathogen as early as possible and achieving accurate diagnosis are essential in infected patients. We can benefit from careful application of metagenomic next-generation sequencing.