Two cases of Cupriavidus gilardii infection presenting as pneumonia and cholecystitis were reported

RATIONALE: Cupriavidus gilardii is an opportunistic pathogen that rarely causes clinical infections. Due to the absence of definitive antimicrobial susceptibility breakpoints established by the Clinical and Laboratory Standards Institute, diagnosis and treatment remain challenging. We report 2 cases of C. gilardii infection to enhance clinical recognition of this pathogen. PATIENT CONCERNS: Case 1: A 72-year-old female with a history of hypertension, diabetes mellitus, and Parkinson disease presented with fever for > 10 days, accompanied by cough and chest tightness. Auscultation revealed coarse breath sounds bilaterally. Case 2: A 68-year-old female with a history of diabetes mellitus and sequelae of cerebral hemorrhage presented with fever for > 8 days, mild epigastric tenderness, and a positive Murphy sign. DIAGNOSES: Case 1 was diagnosed with pneumonia. Case 2 was diagnosed with cholelithiasis with acute cholecystitis. INTERVENTIONS: Both patients received empirical antibiotic therapy. Sputum (Case 1) and bile (Case 2) cultures confirmed C. gilardii infection. Antimicrobial susceptibility testing guided targeted antibiotic adjustment in Case 1. OUTCOMES: Both patients became afebrile, showed clinical improvement, and were discharged. LESSONS: C. gilardii infection should be suspected in immunocompromised or elderly patients with refractory fever, especially those with underlying neurological or cerebrovascular conditions. Early identification by MALDI-TOF MS and timely susceptibility testing are critical for guiding effective treatment, as this pathogen exhibits intrinsic resistance to multiple antibiotics, including carbapenems and aminoglycosides.