Etiology, Pathogenesis, Clinical Stages, Morphology, and Complications of Pneumonia

Pneumonia is an inflammatory condition of the lungs primarily caused by infections. Understanding its etiology, pathogenesis, clinical stages, morphology, and complications is crucial for effective management.

Etiology

Pneumonia can be caused by various pathogens, including bacteria (e.g., Streptococcus pneumoniae), viruses (e.g., Influenza virus), fungi, and other microorganisms.

Pathogenesis

The disease process begins with microbial invasion, followed by an inflammatory response that leads to alveolar damage and fluid accumulation.

Clinical Stages of Pneumonia

Early Phase

Characterized by initial symptoms such as fever, cough, and malaise.

Progressive Phase

Patients experience worsening respiratory symptoms, including dyspnea and sputum production.

Resolution Phase

With appropriate treatment, inflammation subsides, and pulmonary function improves.

Morphology

Pneumonia presents as lung consolidation, alveolar exudates, and inflammatory cell infiltration.

Complications

• Sepsis
• Pleural effusion
• Lung abscess
• Respiratory failure