EC Clinical and Medical Case Reports

Introduction: Chryseobacterium gleum is a rare non-fermenting Gram-negative bacillus increasingly recognized as an opportunistic healthcare-associated pathogen. It is mainly associated with bacteremia, ventilator-associated pneumonia, urinary tract infections, and catheter-related infections, particularly in patients with prolonged hospitalization and significant comorbidities. Reports of C. gleum bacteremia remain uncommon worldwide.

Case Report: We report the case of a 44-year-old Moroccan man admitted to the intensive care unit for severe heart failure. During a prolonged hospital stay, he developed persistent fever, marked inflammatory syndrome, and hemodynamic instability. Two blood cultures collected on separate days became positive after 14 and 16 hours of incubation and yielded Chryseobacterium gleum, identified by matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility testing revealed resistance to β-lactams and carbapenems, while susceptibility to amikacin, fluoroquinolones, trimethoprim-sulfamethoxazole, tigecycline, and colistin was preserved. The diagnosis of true bacteremia was supported by the positivity of multiple blood cultures, a short time to positivity, and a clinical presentation consistent with severe sepsis. Despite targeted antimicrobial therapy, the patient died from refractory cardiogenic and septic shock.

Conclusion: This report describes, to our knowledge, the first documented case of Chryseobacterium gleum bacteremia in Morocco. It highlights the importance of considering this emerging opportunistic pathogen in critically ill patients with prolonged hospitalization. Rapid identification by MALDI-TOF MS and appropriate antimicrobial susceptibility testing are essential for accurate diagnosis and optimal therapeutic management.

Keywords: Chryseobacterium gleum; Bacteremia; Bloodstream Infection; MALDI-TOF MS; Antimicrobial Resistance; Intensive Care Unit; Case Report

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