An 85-year-old male with a tumour in his right lung was admitted to Internal Diseases Ward to continue treatment after suffering a sudden cardiac arrest. An empiric antibiotic therapy with amoxycillin was introduced due to increased inflammation markers. Blood and sputum were collected. An abundant growth of AmpC β-lactamase-producing Citrobacter freundii was observed in culture grown from the sputum. The antibiogram showed retained sensitivity to fluoroquinolones. The therapy was modified by replacing β-lactam with ciprofloxacin. Neither clinical nor laboratory improvement were observed. Blood culture indicated sepsis of Acinetobacter baumannii etiology. The strain was suspected of producing OXA carbapenemase (CARBA test positive), KPC (-), MBL (-). Antibiogram illustrated retained sensitivity to gentamicin and colistin with complete resistance to ciprofloxacin. Another modification in treatment was implemented and ciprofloxacin was replaced with colistin.
Citrobacter freundii and Acinetobacter baumanii infection in a patient with neoplastic lung disease – Case report. Doi: 10.26444/aaem/140111
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