Community-acquired pneumonia is defined as the infection of lung parenchyma which is not acquired in the hospital, long-term care facility, or another recent contact with health care system. It causes significant morbidity and mortality in adults.

Community-acquired Pneumonia is caused by:-

• Streptococcus pneumonia
• Haemophilus influenza
• Chlamydia species
• Legionella species
• Respiratory viruses.

Symptoms of Pneumonia:-

• Fever
• Cough
• Increased yellowish sputum production
• Chest pain which is more of deep inspiration
• Breathlessness
• Altered mental state( particularly in old age)
• Hypotension (low blood pressure)

Investigations Recommended for Pneumonia :

• Complete blood count
• Kidney function test
• Liver function test
• Sputum examination for gram stain, AFB Stain, culture sensitivity
• Blood culture and sensitivity
• Chest X-ray
• Serum procalcitonin(optional)

Treatment for Pneumonia:-

The decision regarding inpatient versus outpatient treatment is based on CURB 65 criteria. There are 5 variables in this scoring system (each variable is given one point if the total score is two or more than patient should be admitted and treated if the score is three or more than ICU admission is advised).

Variables are:-

• Confusion
• Blood urea nitrogen level>20mg/dl
• Respiratory rate > 30 breaths per minute
• Blood pressure (Systolic<90mm of Hg or diastolic <60mm of Hg
• Age more than 65 years

Empirical antibiotics:

• If the patient has no comorbidities then outpatient treatment should be with macrolides or doxycycline.
• If the patient has comorbidities and/or antibiotic use within last three months then outpatient treatment should be with beta-lactam antibiotics plus macrolides or respiratory quinolones should be used as monotherapy.
• In non ICU inpatients treatment should include beta-lactam antibiotics plus macrolide or respiratory quinolone(levofloxacin)
• In Icu patients beta-lactam antibiotics plus IV, Azithromycin/respiratory quinolones should be used
• If there is a risk factor for pseudomonas antipseudomonal antibiotic should be added, if there is a risk factor for MRSA Vancomycin or linezolid should be added.
• If there is a suspicion of swine flu oseltamivir should be added.

Complications associated with Pneumonia:-

• Septic shock
• Metastatic infections
• Empyema
• Cavity formation

Indication for CT SCAN chest:-

• Pneumonia not improving after 48-72 hours of therapy
• Suspicion of complications
• Alternative diagnosis.