Atypical Pneumonia

Atypical Pneumonia

Atypical pneumonia is a term used to distinguish from typi-cal pneumonia caused by Streptococcus pneumoniae. Earlier any patient with sudden onset of fever, chills, pleuritic pain, and expectoration of blood-tinged sputum was believed to present with typical pneumonia caused by S. pneumoniae. The patients not showing these characteristic manifestations were referred to as having atypical pneumonia. M. pneumoniae, Chlamydia pneumoniae, and Legionella pneumophila are three importantagents responsible for atypical pneumonia. In this condition, these pathogens are usually not isolated from sputum by rou-tine culture methods.

      Beta-lactam antibiotics are usually ineffective against Mycoplasma because of the absence of cell wall, and these anti-biotics usually act by inhibiting synthesis of cell wall. Penicillin and cephalosporins are ineffective against all these pathogens because they do not show intracellular penetration in these pathogens.