Prognostic factors of community-acquired pneumonia in patients with pathological lungs

Introduction : Community-acquired pneumonia (CAP) is a common condition of the lower respiratory tract. <bold>Aim:</bold> To determine prognostic factors of CAP in pathological lungs. Methods : Comparative retrospective study including 127 patients hospitalized for CAP. These patients were divided into two groups: group 1 (G1=38): patients with underlying chronic pulmonary pathology and group 2 (G2=89): patients with healthy lungs. <bold>Results:</bold> Chronic pulmonary pathologies in G1 were dominated by chronic obstructive pulmonary disease (n = 16), bronchiectasis (n = 7) and pulmonary fibrosis (n = 8). Compared to patients in G2, CAP in patients in G1 was more severe with a mean ambient air saturation (89% versus 93%, p = 0.03) and systolic blood pressure on admission (115 mmHg versus 122 mmHg, p = 0.048) lower. Mean PaCO2 (40 mmHg versus 31 mmHg, p = 0.015) and mean bicarbonate level (25 mmol/L versus 22 mmol/L, p = 0.046) were higher in G1. G1 patients had more smoking (72% versus 42.9%, p = 0.025), less chest pain (24% versus 54.3%, p = 0.01) and less pleural effusion on radiography thoracic (32% versus 58.8%, p = 0.04). The use of acute oxygen therapy was more frequent (68% versus 42.9%, p = 0.05) in G1 with a higher average oxygen flow (3.2 L/min versus 1.34 L/ min, p = 0.04). The frequency of complications such as abscess (p = 1), sepsis (p = 1) and death (p = 0.06) was comparable between the groups. <bold>Conclusion:</bold> The presence of underlying pulmonary pathology constitutes a factor in the immediate severity of community-acquired acute pneumonia.