Pneumonia , definition, symptoms , treatment

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1. Pneumonia Dr Okanga. N

2. is an infection of the pulmonary parenchyma. The context in which pneumonia develops is highly suggestive of the likely organism(s) involved. Classification – Community acquired, Hospital acquired and ventilator associated pneumionias . Lobar pneumonia - homogeneous consolidation of one or more lung lobes, often with associated pleural inflammation; bronchopneumonia - refers to more patchy alveolar consolidation associated with bronchial and bronchiolar inflammation.

3. Pathophysiology Pneumonia results from the proliferation of microbial pathogens at the alveolar level and the host’s response to those pathogens. Microorganisms gain access to the lower respiratory tract usually by aspiration from the oropharynx, rarely via hematogenous spread (e.g., from tricuspid endocarditis) or by contiguous extension from an infected pleural or mediastinal space. Small-volume aspiration occurs frequently during sleep (especially in the elderly) and in patients with decreased levels of consciousness. Resident alveolar macrophages kill pathogens that manage to reach the alveoli. Only when the capacity of the alveolar macrophages to ingest or kill the microorganisms is exceeded does clinical pneumonia become manifest.

4. Factors that predispose to pneumonia Cigarette smoking Upper respiratory tract infections Alcohol Glucocorticoid therapy Old age Recent influenza infection Pre-existing lung disease HIV Indoor air pollution

5. Organisms causing community-acquired pneumonia

6. Clinical features Presentation - Acute illness. Systemic features - fever, rigors, shivering and malaise. Delirium may be present. Appetite ↓, Headache. Pulmonary symptoms – Cough; short, painful and dry, but later is accompanied by the expectoration of mucopurulent sputum. Pleuritic chest pain may be a presenting feature and on occasion may be referred to the shoulder or anterior abdominal wall. Physical exam - ↑respiratory rate and use of accessory muscles of respiration. Palpation may reveal increased or decreased tactile fremitus, and the percussion note can vary from dull to flat, reflecting underlying consolidated lung and pleural fluid, respectively. Elderly patients - Presentation may not be so obvious, May initially display new-onset or worsening confusion and few other manifestations

7. Labs Haemogram - Very high (> 20 × 109/L) or low (< 4 × 109/L) WBC: marker of severity, Neutrophil leucocytosis > 15 × 109/L: suggests bacterial aetiology , Haemolytic anaemia : occasional complication of Mycoplasma Urea and electrolytes Urea > 7 mmol/L marker of severity, ↓Na: marker of severity, Liver function tests - Abnormal if basal pneumonia inflames liver, Hypoalbuminaemia : marker of severity ESR /CRP -non-specifically elevated Blood culture - Bacteraemia : marker of severity Pulse oximetry - SPO₂ < 93%, marker of severity.

8. Sputum samples - Gram stain, culture and antimicrobial sensitivity testing. Chest X-ray - Lobar pneumonia; Patchy opacification evolves into homogeneous consolidation of affected lobe. Bronchopneumonia - patchy and segmental shadowing Complications - Para-pneumonic effusion, intrapulmonary abscess or empyema. Pleural fluid - Always aspirate and culture when present in more than trivial amounts, preferably with ultrasound guidance.

9. Lobar Pneumonia of the right middle lobe bronchopneumonia: multifocal lung consolidation bilaterally

10. Management of pneumonia Oxygen - should be administered to all patients with tachypnoea, hypoxaemia , hypotension or acidosis with the aim of maintaining the Pa O2 ≥ 8 kPa (60 mmHg) or SP O2 ≥ 92%. Fluid balance - iv fluids should be considered in those with severe illness, in older patients and those with vomiting. Antibiotic treatment .

11. Antibiotic treatment for community-acquired pneumonia

12. Antibiotic treatment for community-acquired pneumonia

13. Complications of pneumonia

14. Indications for referral to ITU CURB score of 4–5, failing to respond rapidly to initial management Persisting hypoxia ( Pa O2 < 8 kPa (60 mmHg)), despite high concentrations of oxygen Progressive hypercapnia Severe acidosis Circulatory shock Reduced conscious level

15. Prognosis Most patients respond promptly to antibiotic therapy. Fever may persist for several days, chest X-ray takes several weeks or even months to resolve, Delayed recovery suggests either that a complication has occurred or that the diagnosis is incorrect.

16. Hospital acquired pneumonia

17. Suppurative pneumonia, aspiration pneumonia and pulmonary abscess

18. Pneumonia in the immunocompromised patient.