Omadacycline for treating severe Legionella pneumonia in a patient following initial treatment failure: A case report

Background: Fluoroquinolones and macrolides are the preferred antibiotics for the treatment of Legionnaire's disease. However, adverse drug reaction and limited utility in cases of organ insufficiency are major problems. Omadacycline is a novel tetracycline antibiotic with a good safety profile and in vitro antibacterial activity against Legionella, but lacking validation by clinical data.Case Presentation:Here, we report a case of severe pneumonia caused by Legionella infection in which the patient was empirically treated with antibiotics, including moxifloxacin, after admission but had a poor clinical outcome with severe hepatic and renal insufficiency. After Legionella infection was confirmed by metagenomic next-generation sequencing, the patient was switched to omadacycline antibiotic therapy and eventually discharged.Conclusions:The results of this study suggest that metagenomic next-generation sequencing can facilitate early diagnosis of Legionnaire's disease, and omadacycline can be an alternative antibiotic treatment for severe Legionnaire's disease, especially in cases of antibiotic resistance or multiple organ failure.