PURPOSE: Moraxella catarrhalis is known as an important pathogen in the exacerbation of chronic obstructive pulmonary disease. The aim of this study was to assess the clinical and pulmonary thin-section computed tomography (CT) findings in patients with acute Moraxella catarrhalis pulmonary infection.
METHODS: Thin-section CT scans obtained between January 2004 and March 2009 from 292 patients with acute Moraxella catarrhalis pulmonary infection were retrospectively evaluated. Patients with concurrent infection, including Streptococcus pneumoniae (n=72), Haemophilus influenzae (n=61), or multiple pathogens were excluded from this study. Thus, our study group comprised 109 patients (66 male, 43 female; age range, 28-102 years, mean, 74.9 years). Among the 109 patients, 34 had community-acquired and 75 had nosocomial infections.
RESULTS: Clinical and pulmonary CT findings in the patients were assessed. Underlying diseases included pulmonary emphysema (n=74), cardiovascular disease (n=44), or malignant disease (n=41). Abnormal findings were seen on CT scans in all patients and included ground-glass opacity (n=99), bronchial wall thickening (n=85) and centrilobular nodules (n=79). These abnormalities were predominantly seen in the peripheral lung parenchyma (n=99). Pleural effusion was found in eight patients. No patients had mediastinal and/or hilar lymph node enlargement.
CONCLUSIONS: Moraxella catarrhalis pulmonary infection was observed in elderly patients, often in combination with pulmonary emphysema.
CLINICAL IMPLICATIONS: Moraxella catarrhalis pulmonary infection is an important type of pneumonia because these infections (1) exacerbate chronic obstructive pulmonary disease; (2) cause pneumonia, particularly in older adults; and (3) comprise a nosocomial respiratory tract pathogen. Therefore, it is essential to identify the risk factors associated with poor outcome and to evaluate the radiological findings as quickly as possible for timely initiation of appropriate management and treatment. This work will contribute to reduce the mortality of patients with acute Moraxella catarrhalis pulmonary infection.
DISCLOSURE: The following authors have nothing to disclose: Tomoko Nakayama, Fumito Okada, Yumiko Ando, Asami Ono, Masanori Watanabe, Hajime Takaki, Hiromu Mori
No Product/Research Disclosure Information