Lung Infection Due to Species Infrequently Isolated in the Community Setting: Klebsiella variicola and Acinetobacter baumannii

The authors report a case of pulmonary infection caused by two typically nosocomial bacterial agents, Klebsiella variicola and Acinetobacter baumannii, simultaneously evidenced in a 65-year-old male patient from the community. Both diagnoses were established after culture and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis of sputum, and the patient was successfully treated with oral levofloxacin, with microbiological eradication subsequently confirmed by three negative follow-up sputum cultures. The singularity of this case challenges the conventional paradigm distinguishing community- and hospital-acquired infections and underscores the importance of maintaining a high index of suspicion for atypical pathogens in routine clinical practice.