[Pasteurella multocida Pneumonia with Hemoptysis in an Immunocompetent Case]

Pasteurella species are gram-negative bacilli found in healthy pets' oropharynx and gastrointestinal tract flora. In humans, skin and soft tissue infections develop most frequently with the bite or scratching of animals such as cats or dogs. At the same time, they cause infections in the respiratory tract, mainly in patients with chronic lung disease or immunosuppressive patients. In this case report, a rare case of pneumonia caused by P.multocida bacteria in a patient with bronchiectasis was presented. A young male patient was admitted to the emergency department of our hospital with complaints of hemoptysis, cough with phlegm, and weight loss. The patient's blood pressure was 140/82 mmHg and SO2= 94%. Rales and rhonchi were detected in the lower left lung during the examination. Standard thorax tomography revealed prominent cystic structures and pneumonic infiltrates in the left lower lobe. Laboratory findings were normal. The Coronavirus disease-2019 (COVID-19) quantitative real-time polymerase chain reaction (qRt-PCR) test was found to be negative in the nasopharyngeal swab sample taken from the patient. Fiberoptic bronchoscopy was performed on the patient to investigate the presence of endobronchial lesion or foreign body aspiration. Culture and cytological evaluation was requested from the bronchial lavage taken. Gram-negative coccobacilli were seen among dense polymorphonuclear leukocytes in the Gram stain of the sample. Acid-fast bacilli were not detected with Ehrlich Ziehl Neelsen stain. In the lavage culture evaluated after 24 hours, colonies growing in blood and chocolate media were stained and gramnegative coccobacilli were observed. The isolate was identified as 96.0% P.canis with the automated Vitek 2 (Biomerieux, France) system. It was determined that the isolate was susceptible to levofloxacin, trimethoprim-sulfamethoxazole, amoxicillin-clavulanic acid, penicillin, ciprofloxacin and cefotaxime in the antibiogram performed by disc diffusion test according to EUCAST v13.0 guideline criteria. Sequence analysis of the isolate obtained from the culture was performed on the ABI Prism 310 Genetic Analyzer (Applied Biosystems, USA). Sequence analysis of the isolate revealed 99.85% homology with P.multocida (GenBank accession no: NG_115137.1). Although Pasteurella multocida pneumonia is not commonly observed, the presence of underlying bronchiectasis in this patient facilitated the establishment of the bacteria. In order not to miss the diagnosis of pneumonia due to P.multocida, microbiological evaluation and molecular typing should be performed in the samples taken from the respiratory tract in patients with chronic respiratory diseases such as bronchiectasis.