Semaglutide-Induced Silent Aspiration: An Unrecognised Cause of Organising Pneumonia

We present the case of a female in her 20s with a history of obesity and obstructive sleep apnea (OSA) on continuous positive airway pressure (CPAP) therapy, who developed silent microaspiration pneumonitis and organising pneumonia (OP) following the recent initiation of Semaglutide for weight loss. She initially presented with shortness of breath, a non-productive cough and subjective fevers of 1-week duration. On admission, she was hypoxic, requiring 6 L of oxygen via nasal cannula and chest imaging revealed right lung infiltrates concerning for community-acquired pneumonia. Despite completing antibiotics, her symptoms and imaging progressively worsened. An extensive infectious and autoimmune workup was conducted, but no clear aetiology was identified. Diagnostic bronchoscopy revealed severe gastroesophageal reflux disease (GERD) with evidence of microaspiration, leading to the diagnosis of organising pneumonia (OP) secondary to silent aspiration. Although long-acting glucagon-like peptide-1 (GLP-1) agonists like Semaglutide do not typically cause reflux, they are known to delay gastric emptying, which can increase intragastric pressure. In this patient, the combination of delayed gastric emptying from Semaglutide, obesity and CPAP therapy likely contributed to reflux and silent aspiration. The patient was successfully treated with corticosteroids and proton pump inhibitors, resulting in clinical and radiographic improvement. This case highlights the potential for silent aspiration in patients on GLP-1 receptor agonists, especially those on CPAP therapy, and underscores the importance of monitoring for reflux-related complications in these patients.