Possible lansoprazole-induced eosinophilic syndrome

Area of Science:

• Gastroenterology
• Rheumatology
• Pharmacology

Background:

• Proton pump inhibitors like lansoprazole are widely used for acid-related gastrointestinal disorders.
• Eosinophilic disorders, including eosinophilia-myalgia syndrome and eosinophilic fasciitis, can present with significant musculoskeletal pain.

Observation:

• A 50-year-old woman developed severe myalgia and eosinophilia within a week of initiating lansoprazole.
• Her symptoms gradually improved after discontinuing lansoprazole and initiating prednisone therapy.

Findings:

• This case represents the first reported instance of lansoprazole-associated eosinophilic syndrome.
• The clinical presentation suggested a potential overlap between eosinophilia-myalgia syndrome and eosinophilic fasciitis.

Implications:

• This case highlights the importance of considering medication side effects, particularly lansoprazole, in patients presenting with unexplained myalgia and eosinophilia.
• It underscores the need for a broad differential diagnosis for eosinophilic disorders, recognizing potential drug-induced etiologies.