Community-acquired pneumonia caused by Kluyvera intermedia: A rare case report.

Background: Kluyvera intermedia is a rare Gram-negative bacillus that predominantly functions as an opportunistic pathogen. Commonly found in environmental sources such as freshwater and soil, it has been infrequently reported in human infections, often leading to underrecognition in clinical practice. Because it can resemble more prevalent pathogens, accurate identification is crucial for effective management of infections. Case report: We report a case of pneumonia caused by Kluyvera intermedia in a 55-year-old male with a 10-year history of well-controlled hypertension. The patient initially presented with classic pneumonia symptoms, including fever, cough, and right-sided chest pain. Although he received empirical treatment with Cefotaxime Sodium and Levofloxacin at the local hospital, follow-up CT scans revealed further enlargement of the pulmonary lesions. To investigate the underlying etiology, the patient underwent MRI-guided lung biopsy at our hospital, and culture of the aspirated fluid identified Kluyvera intermedia as the causative pathogen. He was subsequently treated with Ceftizoxime sodium and Levonidazole Sodium Chloride Injection, resulting in significant clinical improvement. The patient was discharged after 22 days of hospitalization. Conclusion: Further accumulation and reporting of cases will enhance the recognition of the clinical characteristics of Kluyvera intermedia. These studies will not only expand our understanding of this rare pathogen but also provide a foundation for improved response strategies, thereby ensuring better management of similar infections in future clinical practice.