Typical Presentation of Legionella pneumophila Community-Acquired Pneumonia

Abstract

Legionnaires’ disease (LD) is often present as a severe form of pneumonia and is caused by the intracellular pathogen Legionella pneumophila which has an atypical presentation with nonspecific radiographic patterns and clinical presentation1. The presence of extra-pulmonary complications that could affect the central nervous system, heart, liver, gastrointestinal tract and kidney are the main differences to the typical presentation of bacterial pneumonia2. L. pneumophila serogroup 1 is the most comment species causing LD in Europe and America, accounting for approximately 90% of the cases3. However, Legionella longbeacheae, another species of Legionella, is involved in approximately 30% of the cases presented in Australia and New Zealand4,5. Mortality rate of pneumonia caused by L. pneumophila is around 10% but this rate is higher in cases of nosocomial outbreaks and in immunosuppressed patients with approximately 25% of mortality.