Severe Fulminant Hypoxemic Respiratory Failure Secondary to Mycoplasma Pneumoniae in a Previously Healthy Adult Patient: A Case Report
Authors:   Hôpital Montfort, Clinical Pharmacist, Assistant Clinical Professor, University of Ottawa School of Pharmaceutical Sciences, Institut du Savoir Montfort, Ottawa, Canada, Khan Imran , Thabet Pierre ,   Hôpital Montfort, Department of Critical Care, Assistant Clinical Professor, University of Ottawa School of Pharmaceutical Sciences, & Institut du Savoir Montfort, Ottawa, Canada, Kovacs Bernadett ,   Critical Care Medicine, Chief of Critical Care Medicine, Montfort Hospital, University of Ottawa, Canada, Elias Sarah ,   General Internal Medicine Resident, Ottawa Hospital, Canada, Dann Melissa ,   Medical Student, Montfort Hospital, University of Ottawa, Canada, Richler Caitlin ,   Hôpital Montfort, Clinical Pharmacist, Assistant Clinical Professor, University of Ottawa School of Pharmaceutical Sciences, Ottawa, Canada, Landry Christine ,   Hôpital Montfort, Clinical Pharmacist, Director, Pharmacy Program and Accreditation, School of Pharmaceutical Sciences, University of Ottawa, Ottawa, Canada, Morin Sydney ,   Hôpital Montfort, Clinical Pharmacist, Assistant Clinical Professor, University of Ottawa School of Pharmaceutical Sciences, Ottawa, Canada, Do Kimberly ,   Hôpital Montfort, Clinical Pharmacist, Assistant Clinical Professor, University of Ottawa School of Pharmaceutical Sciences, Institut du Savoir Montfort, Ottawa, Canada
Published: January 2025

Background: Mycoplasma pneumonia (M. pneumoniae) is a common cause of community-acquired pneumonia, usually presenting as a mild respiratory illness. However, severe complications, including Acute Respiratory Distress Syndrome (ARDS), can occur, even in previously healthy individuals. The Centers for Disease Control and Prevention has reported an increase in M. pneumoniae infections, particularly among young children, coinciding with rising cases of macrolide-resistant strains. Early diagnosis remains challenging due to the organism’s atypical presentation, and the need for targeted therapy is critical to managing severe cases effectively.

Case Presentations: A 40-year-old previously healthy male presented with one week of progressively worsening respiratory symptoms, including fatigue, myalgias, and a productive cough. Initial investigations revealed leukocytosis, and chest imaging showed bilateral pneumonia with areas of consolidation. Despite empiric therapy with ceftriaxone and azithromycin, his condition worsened, and he required mechanical ventilation for ARDS on Day 3. Bronchoalveolar Lavage (BAL) confirmed M. pneumoniae as the causative pathogen. After de-escalating antimicrobial therapy and following the ARDS mechanical ventilation protocol with prone positioning, the patient was extubated on Day 8 and, by Day 14, required only minimal oxygen support.

Conclusions: Severe M. pneumoniae infections, such as ARDS, can occur in previously healthy individuals, requiring rapid diagnosis and intensive care. This case underscores the importance of Polymerase Chain Reaction (PCR) testing and Bronchoalveolar Lavage (BAL) for accurate diagnosis. With the increasing virulence of M. pneumoniae, potentially due to macrolide resistance, early diagnosis and timely treatment with azithromycin remain essential, although alternative therapies may be needed for resistant strains. Ongoing surveillance and updated treatment strategies are critical to managing this evolving clinical challenge.