Community-Acquired Pneumonia in Alcoholic Patients

Abstract

In Brief Recent reports have identified alcoholism to have an important public health impact and cause a substantial loss of lives worldwide. For a long time alcoholism has been identified to favor pulmonary infections. But only in the last 2 decades the alterations induced by ethanol to the complex mechanisms of lung defense have been recognized. Alcohol alters lung defenses on all levels. It is known to favor oropharyngeal colonization by potentially pathogenic bacteria, aspiration by altering the cough reflex, and to decrease ciliary motility and surfactant production. Innate and adaptive immune responses on the systemic and alveolar level are compromised by alteration of cytokines, decreased chemotaxis, and phagocytic activity of alveolar macrophages and neutrophils. Recent data suggest that Streptococcus pneumoniae is the leading pathogen responsible for community-acquired pneumonia in alcoholic patients. However, series have reported Klebsiella pneumoniae, Legionella pneumophilia, and other Gram-negative enterobacteriaceae to be frequent, especially in severe cases. Anaerobes may play a role if aspiration after acute intoxication is the cause. The clinical course of community-acquired pneumonia in alcoholic patients is more severe leading to more intensive care unit care, longer hospital stay, and a delay of clinical improvement after initiation of therapy. Convincing data are available showing a predisposition of alcoholic patients for the development of acute respiratory distress syndrome. Some issues still remain controversial as to the rate of multiresistant bacteria or an increased mortality. Regarding the treatment of alcoholic patients, particularities and potential modifiers of antimicrobial treatment have to be accounted for. These include other frequent comorbid conditions such as chronic obstructive pulmonary disease and liver disease, complex socioeconomic and psychiatric conditions, and poor adherence to therapy. For a long time alcoholism has been identified to favor pulmonary infections. But only in the last 2 decades the alterations induced by ethanol to the complex mechanisms of lung defense been recognized. The following review provides an overview of the pathophysiology, epidemiology, and particular clinical aspects of community-acquired pneumonia in alcoholic patients.