COMMUNITY ACQUIRED PNEUMONIA
Acute infection of pulmonary parenchyma Causative Organism : Streptococcus pneumoniae (pneumococci) - most common Haemophilus influenzae - 2nd most common Mycoplasma pneumonia Chlamydia pneumonia Rare : Legionella Staphylococcus aureus Gram negative organism ( klebsiella , pseudomonas) virus (adenovirus , meta pneumo virus) In India : - 20% cases of CAP - Tuberculosis - 40% cases of CAP - Not established PATHOLOGY : Initially there is a inhalational of bacteria into the lungs results in phase of Edema ↓ proteinaceous exudates developed in the alveoli (so there can be a crepitation, crackles of bronchial breathing in the patient and subsequently patients enter into the following phases) Red hepatization - RBC + Neutrophils (3-4 days) Grey hepatization - RBC lysis + Neutrophils (it signifies successful)(5 -7 days) Resolution - here Macrophages predominantly present because these cells restore the normal tissue Typical / lobar pneumonia : Lobar consolidation causative org...