Pneumonia is an inflammation of lung tissue caused by infectious agents, classified as community-acquired or nosocomial based on acquisition location. The document details its pathophysiology, risk factors, clinical features, diagnostic methods, and treatment strategies including antibiotic therapy and prevention measures like vaccination. It highlights the significant impact of pneumonia on morbidity and mortality globally, particularly in developing countries.

1. Pneumonia
Dr. Akhilesh Sah
Prepared by:

3. Pneumonia:
Pneumonia is a inflammation and consolidation of lungs tissue due to an
infectious agent.
• Pneumonia is frequently categorized based on site of acquisition.
• ●Community-acquired pneumonia (CAP) refers to an acute infection of the
pulmonary parenchyma acquired outside of the hospital.
• ●Nosocomial pneumonia refers to an acute infection of the pulmonary
parenchyma acquired in hospital settings and encompasses both hospital-
acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP).
• •HAP refers to pneumonia acquired ≥48 hours after hospital admission.
• •VAP refers to pneumonia acquired ≥48 hours after endotracheal
intubation.

4. • Pneumonia causes inflammation in the alveoli
• Alveoli are filled with fluid or pus, making difficulty to breathe.
• Affects alveoli rather than the bronchi
• CONSOLIDATION:
Inflammatory induration of a normally aerated lung due to the
presence of cellular exudative in alveoli
• More Likely to occur due to:
• immunocompromised
• potent microbe

5. Anatomical classification
• Bronchopneumonia(patchy inflammation of multiple lobes)
• Lobar pneumonia(involves one or more lobe)
• Interstitial pneumonia(inflammatory inflitrate of alveolar wall)
Etiological classification
• Bacterial infection
• Viral infection
• Fungal infection

6. COMMUNITY ACQUIRED PNEUMONIA

7. Incidence.
• It is a major cause of morbidity and mortality with an incidence of 20-
30% in the developing countries and 3-4% in developed countries.
Since pneumonia is not a reportable illness its incidence is based on
crude estimates. It is estimated that Nepal, India, Bangladesh and
Indonesia account for 40% of global acute respiratory infections.In
Nepal, pneumonia and enteric fever was found to be the main cause
of fever.
• Mortality ranges from about 5-35% with a worse prognosis in older
people, men, and people with chronic disease.
• Despite the advances in diagnostic techniques, in approximately 50%
of the cases, etiology is not found

8. Risk factors
• Old age population
• Imunocompromised
• Chronic diseases:COPD, Asthma, DM, Chronic heart disease, HIV
• Viral respiratory tract infection
• Impaired airway protection
• Smoking and alcohol overuse
• Lifestyle: crowded area, low income , homeless, exposure to
environmental toxins
• Malnutrition

9. Etiology(Causes)
• Streptococcus pneumoniae (pneumococcus) and respiratory viruses but
in most of cases no pathogens are detected
• Most identified causes:
• Typical bacteria Atypical
• S. pneumoniae (most common) legionella spp
• Haemophilus influenzae Mycoplasma pneumoniae
• Moraxella catarrhalis chlamydia pneumoniae
• Staphylococcus aureus Chlamydia Psittaci
• Group A streptococci
• Pseudomonas Coxiella Burnetii,

10. Cont.
Respiratory viruses
• Influenza A and B viruses
• Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
• Other coronaviruses (eg, CoV-229E, CoV-NL63, CoV-OC43, CoV-HKU1)
• Rhinoviruses
• Parainfluenza viruses
• Adenoviruses
• Respiratory syncytial virus

11. Cont.
Fungi:
• Cryptococcus spp
• Histoplasma capsulatum
• Coccidioides spp

12. Pathogenesis

13. Pathology
Stages of Pneumonia
1. Stage of congestion:
2. Stage of red hepatization
3. Stage of grey hepatization
4. Stage of Resolution

14. Cont..

15. Clinical features
Symptoms
• High grade fever
• Cough productive/non productive
• Chest pain
• Breathlessness
• Othes:headache, loss of appetite, confusion, excessive sweating

16. Cont..
Signs :
• Febrile
• Tachypnoea
• Cynosis
• Hypotension
• Altered sensorium
• Confusion
Chest examination: percussion dull, bronchial breathe sounds, crackles,
Pleural rub

17. Sounds

18. Investigation
• CBC: Neutrophilic Leucocytosis
• RFT: urea >20mg/dL, Hyponatremia
• Sputum culture
• Gram stain
• AFB
• Giemsa stain: chlamydia , histoplasma
• KOH mount
• Chest xray
• Others:, ESR, CRP, Pro-Calcitonin,, ABG, HRCT CHEST, LFT
• Invasive:bronchoscopy, thoracoscopy, biopsy, aspiration

25. RUL RML

26. RUL Bronchopneumonia

27. Interstitial pneumonia

29. Complication
• Sepsis
• Respiratory failure
• Lung abscess
• Pleural effusion
• ARDS
• Pneumothorax
• Renal failure
• Multi-organ failure

30. Prevention
The three primary pillars for the prevention of CAP are
• Smoking cessation (when appropriate)
• Influenza vaccination for all patients
• Pneumococcal vaccination for at-risk patients

31. Management/Treatment/Approch

32. Severity score

33. PSI
SCORE(pneumoni
a severity index)

34. Suitable area for admission

35. Treatment
The most important aspects of management include
• oxygenation,
• fluid balance and
• antibiotic therapy.
• In severe or prolonged illness, nutritional support may be required.

36. Oxygenation
• Oxygen should be administered to all patients with tachypnoea,
hypoxaemia, hypotension or acidosis with the aim of maintaining the
PaO2 ≥ 60 mmHg or SaO2 ≥ 92%

37. Fluid balance
• Intravenous fluids should be considered in those with severe illness,
in older patients and those with vomiting. It may be appropriate to
discontinue hypertensive agents temporarily. Otherwise, an adequate
oral intake of fluid should be encouraged. Inotropic support may be
required in patients with shock

38. Antibiotics:
Uncomplicated CAP
Amoxicillin 500 mg 3 times daily orally
If patient is allergic to penicillin
Clarithromycin 500 mg twice daily orally or Erythromycin 500 mg 4 times
daily orally
If Staphylococcus is cultured or suspected
Flucloxacillin 1–2 g 4 times daily IV plus Clarithromycin 500 mg twice daily IV
If Mycoplasma or Legionella is suspected
-Clarithromycin 500 mg twice daily orally/IV or Erythromycin 500 mg 4 times
daily orally/IV plus
-Rifampicin 600 mg twice daily IV in severe cases

39. Cont..
Severe CAP
• Clarithromycin 500 mg twice daily IV or Erythromycin 500 mg 4 times
daily IV plus
• Co-amoxiclav 1.2 g 3 times daily IV or Ceftriaxone 1–2 g daily IV or
Cefuroxime 1.5 g 3 times daily IV or
• Amoxicillin 1 g 4 times daily IV plus flucloxacillin 2 g 4 times daily IV
Physiotherapy:

40. Cont.(for knowledge)
• For most patients aged <65 years who are otherwise healthy and have
not recently used antibiotics, we typically use oral amoxicillin plus a
macrolide (eg, azithromycin or clarithromycin) or doxycycline.
Generally, we prefer to use a macrolide over doxycycline
• For patients who cannot use any beta-lactam, we select a respiratory
fluoroquinolone (eg, levofloxacin, moxifloxacin, gemifloxacin)
• or patients who can use cephalosporins, we use a third-generation
cephalosporin (eg, cefpodoxime) plus either a macrolide
or doxycycline.

41. • For most patients without suspicion for MRSA or Pseudomonas, we
treat with a beta-lactam
(eg, ceftriaxone, cefotaxime, ceftaroline, ampicillin-sulbactam,) plus a
macrolide (eg, azithromycin or clarithromycin) or a beta-lactam plus a
respiratory fluoroquinolone (eg, levofloxacin or moxifloxacin)

42. • For patients with known colonization or prior infection
with Pseudomonas, recent hospitalization with IV antibiotic use, or
other strong suspicion for pseudomonal infection, we typically use
combination therapy with both an antipseudomonal beta-lactam
(eg, piperacillin-tazobactam, cefepime(2g
bd), ceftazidime, meropenem, or imipenem) plus an
antipseudomonal fluoroquinolone (eg, ciprofloxacin or levofloxacin).
The selection of empiric regimens should also be informed by the
susceptibility pattern for prior isolates

43. Cont..
For patients with known colonization or prior infection with MRSA or
other strong suspicion for MRSA infection, we add an agent with anti-
MRSA activity, such as vancomycin(15-
20mg/kg/dose) or linezolid(600mg BD)
Others antibiotcs: Aztreonam, carbapenems
STEROIDS:

44. ICU ADMISSION/ indication of referal
• CURB score of 4–5 (see Fig. 17.32), failing to respond rapidly to initial
management
• Persisting hypoxia (PaO2 < 8 kPa (60 mmHg)), despite high
concentrations of oxygen
• Progressive hypercapnia
• Severe acidosis
• Circulatory shock
• Reduced conscious level

45. Vaccination
• Pneumococcal Polysaccharide vaccine
• Inactivated influenza vaccine
• Live attenuated influenza vaccine

46. Community-acquired pneumonia: Empiric outpatient antibiotic selection in adults*

47. Community-acquired pneumonia: Empiric antibiotic selection for adults admitted to the general medical ward*

48. Community-acquired pneumonia: Empiric antibiotic selection for adults admitted to the intensive care unit*

49. Hospital Acquired Pneumonia()
• Hospital-acquired pneumonia (HAP) or nosocomial pneumonia refers
to a new episode of pneumonia occurring at least 2 days after
admission to hospital
• . It is the second most common hospital-acquired infection (HAI) and
the leading cause of HAI associated death.

50. Clinical Feature and Investigation
Same as CAP(community accquired pneumonia)
• The diagnosis should be considered in any hospitalised or ventilated
patient who develops
• purulent sputum (or endotracheal secretions)
• new radiological infiltrates(In xray or CT scan)
• an otherwise unexplained increase in oxygen requirement,
• a core temperature > 38.3°C, and
• a leucocytosis or leucopenia

51. Factors predisposing/Causes
Reduced host defences against bacteria
• Reduced immune defences (e.g. glucocorticoid treatment, diabetes,
malignancy)
• Reduced cough reflex (e.g. post-operative)
• Disordered mucociliary clearance (e.g. anaesthetic agents)
• Bulbar or vocal cord palsy
Aspiration of nasopharyngeal or gastric secretions
• Immobility or reduced conscious level
• Vomiting, dysphagia (N.B. stroke disease), achalasia or severe reflux
• Nasogastric intubation

52. Cont.
Bacteria introduced into lower respiratory tract
• Endotracheal intubation/tracheostomy
• Infected ventilators/nebulisers/bronchoscopes
• Dental or sinus infection
Bacteraemia
• Abdominal sepsis
• Intravenous cannula infection
• Infected emboli

53. Treatment
• The principles of management are similar to those of CAP, focusing on
adequate oxygenation, appropriate fluid balance and antibiotics
• In patients who have received no previous antibiotics, co-amoxiclav or
cefuroxime represents a sensible choice
• If the patient has received a course of recent antibiotics, then
piperacillin/tazobactam or a third-generation
cephalosporin(ceftriazone) should be considered.
• Antipseudomonal cover may be provided by a carbapenem
(meropenem), an anti-pseudomonal cephalosporin or piperacillin–
tazobactam

54. Cont.
• MRSA cover may be provided by glycopeptides such as vancomycin or
linezolid

55. Aspiration pneumonia and Suppurative
Pneumonia
Suppurative and Aspiration Pneumonia are considered together as
clinical feature overlap
is characterised by destruction of the lung parenchyma by the
inflammatory process
develop after the inhalation of septic material during operations on the
nose, mouth or throat, under general anaesthesia, or of vomitus during
anaesthesia or coma, particularly if oral hygiene is poor
Additional risk factors for aspiration pneumonia include vocal cord
palsy, achalasia or oesophageal reflux, and alcoholism

56. Cont.
• The organism(s) isolated from the sputum include Strep.
pneumoniae, Staph. aureus, Streptococcus pyogenes, H. influenzae

57. Clinical features of Aspiration Pneumonia
Symptoms
• Cough with large amounts of sputum, sometimes fetid and blood-
stained
• Pleural pain common
• Sudden expectoration of copious amounts of foul sputum if abscess
ruptures into a bronchus

58. Clinical signs
• High remittent pyrexia
• Profound systemic upset
• Digital clubbing may develop quickly (10–14 days)
• Consolidation on chest examination; signs of cavitation rarely found
• Pleural rub common
• Rapid deterioration in general health, with marked weight loss if not
adequately treated

59. Treatment
• Aspiration pneumonia can usually be treated with amoxicillin and
metronidazole
• MRSA is usually susceptible to a variety of oral non-β-lactam
antibiotics, such as trimethoprim/sulfamethoxazole, clindamycin,
tetracyclines and linezolid, VANCOMYCIN

60. Pneumonia in the immunocompromised
patient
• Patients immunocompromised by drugs or disease (particularly
human immunodeficiency virus (HIV) infection are at increased risk of
pulmonary infection and pneumonia is the most common cause of
death in this group
• low virulence or non-pathogenic, may become ‘opportunistic’
pathogens cause pneumonia
• Depending on the clinical context, clinicians should consider the
possibility of Gram-negative bacteria, especially P. aeruginosa,
viruses, fungi, mycobacteria
• Infection is often due to more than one organism

61. Clinical Feature
• fever,
• cough and
• breathlessness
but are influenced by the degree of immunosuppression
Other similar to other type of pneumonia

62. treatment
• treatment should be based on an established aetiological diagnosis;
• in practice, however, the causative agent is frequently unknown.
• Factors that favour a bacterial aetiology include neutropenia, rapid
onset and deterioration
• broad-spectrum antibiotic therapy should be commenced
immediately, e.g. a third-generation cephalosporin(ceftriazone), or a
quinolone(ciprofloxacin , levofloxacin), plus an antistaphylococcal
antibiotic(amoxicillin), or an antipseudomonal penicillin(piperacillin)

63. Thank you