This document discusses the causative agents and management of pneumonia according to age group and clinical features. It covers viral, bacterial, and atypical causes of pneumonia in different age groups from newborns to children and adolescents. For each type of pneumonia, the document discusses the typical causative organism, clinical presentation, potential complications, and recommended treatment approaches. A variety of bacterial causes are outlined including pneumococcal, staphylococcal, haemophilus, and streptococcal pneumonia. Viral pneumonia, mycoplasma pneumonia, and aspiration pneumonia are also summarized.

1. CAUSATIVE AGENTS OF
PNEUMONIAACCORDING TO
AGE GROUP, CLINICAL
FEATURES AND
MANAGEMENT
Sunil Kumar Daha

2. Pneumonia
• Inflammation of the lung parenchyma
• Classification: 1. Lobar or lobular,
2. Bronchopneumonia and
3. Interstitial pneumonia
• Pathologically, there is consolidation of alveoli,
infiltration of interstitial tissue with inflammatory
cells or both

3. Etiology
• Viral Pneumonia: RSV, Influenza, Parainfluenza and Adenovirus
• Bacterial Pneumonia:
• 1st 2 months: Klibsella, E.coli and gram+ve organisms like pneumocci and
staphylococci
• 3 months – 3 years: S. pneumonia, H. influenzae and staphylococci
• > 3 years: Pneumococci and Staphylococci
• Atypical pneumonia: Chlamydia and Mycoplasma spp.
• Pneumonia in immunocompromised Children: Pneumocystis
Jeroveci, Histoplasmosis, Cocidiomycosis

4.  Risk Factors
• Low birth weight
• Malnutrition
• Vitamin A deficiency
• Lack of breast-feeding
• Passive smoking
• Large family size
• Family history of
bronchitis
• Advanced birth order
• Crowding
• Young age
• Air pollution

5. Pneumococcal pneumonia
• Causative organism : Streptococcous Pneumoniae
• Transmission : Infectious droplets
• Incubation period : 1 – 3 days
• Clinical features:
• Abrupt onset with headache, chills, cough and high fever
• Dry cough but rarely associated with thick rusty sputum
• Pleural pain may be present
• Respiration is rapid
• Grunting, chest in drawing ,difficulty feeding and cyanosis may
be seen in severe cases

7. Pneumococcal pneumonia
• Treatment:
• Penicillin V 250 mg 8-12 hr orally for 7 days
• Penicillin-G 0.5 MU/kg/day IV
• Procaine Penicillin 0.6 MU IM daily, for 7 days
• Amoxycilin (30-40 mg/kg/day for 7 days)
• O2 therapy for cyanosis, respiratory distress
• IV fluid if dehydrated

8. Staphylococcal Pneumonia
• Causative organism : Staphylococci
• Clinical features:
• Usually follows URTI, pyoderma or a purulent disease
• Patient is toxic and sick looking
• Cyanosis may be present
• Rapid progression of signs and symptoms
• Pulmonary infection complicated by disseminated disease
• pneumatoceles ( X-RAY)
•

9. • Treatment:
• Antipyretics to control fever
• Hydration by intravenous fluid
• Oxygen to relieve dyspnea and cyanosis
• Empyema is aspirated and pus is sent for culture and
sensitivity
• Antibiotic therapy with coamoxiclav, or a combination of
cloxacilin and 3rd generation cephalosporin
• If unresponsive, vancomycin, teicoplanin or linezolid is
given
• Therapy to be continued till disappearance of evidence of
disease clinically and radiographically.
Staphylococcal Pneumonia

10. Haemophilus pneumonia
• Causative Organism: Haemophilus influenzae
• Clinical features:
• Gradual onset with nasopharyngeal infection
• Viral infections like influenza virus act synergistically with H.
influenzae
• Moderate fever, dyspnoea, grunting, retraction of lower
Intercostal spaces.
• Complications:
• Bacteremia, pericarditis, empyema, meningitis
and polyarthritis

11. • Treatment:
• Ampicilin at dose of 100mg/kg/day or, coamoxiclav
• Cefotaxime (100mg/kg/day) or ceftriaxone(50-75 mg/kg/day) in
seriously ill patients.
Haemophilus pneumonia

12. Streptococcal pneumonia
• Organism: Streptococcous pyogens
• Clinical features:
• Usually secondary to measles, chicken pox, whooping
cough or influenza
• Abrupt onset with fever, chills, dyspnoea, rapid respiration,
cough, blood streaked sputum
• Signs of bronchopneumonia are usually less pronounced

13. Primary Atypical Pneumonia
• Organism: M. pneumoniae
• Incubation period: 12-14 days
• Clinical features:
• Malaise, headache, fever, sore throat, myalgias and cough
• Cough initially dry, later mucoid with blood streak
• Mild pharyrngeal congestion, unusual dyspnea, cervical lymphadenopathy
and few crepitations
• Hemolytic anemia may be seen
• Treatment:
• Macrolides or Tetracycline (for older children ) for 10 days

14. Pneumonia due to Gram-ve Organisms
• Organism: E.coli, Klebsella and Pseudomanas
• Clinical features:
• Gradual onset
• Minimal signs of consolidation
• Treatment:
• Cephalosporin 3rd generation(cefotaxime or ceftriaxone, 75-
100 mg/kg/day) with or without aminoglycosides for 10 to 14
days
• Ceftazidine or piperacilin-tazobactam for psedomonas
infection

15. Viral pneumonia
• Organism: RSV ( <6 months of age), influenza, Para-influenza
and adeno virus
• Clinical features:
• Fever and/or chills
• Cough , tachypnoea or dyspnoea
• Tachycardia or bradycardia
• Wheezing, rhonchi, rales
• Sternal or intercostal retraction
• Hypoxia, ARDS
• Supportive treatment

16. Pneumonia due to ingestion of aliphatic
hydrocarbon
• Etiology: kerosene (hydrocarbons)
• Clinical features:
• Cough, dysponea, high fever, vomitng, drowsiness and coma
• Treatment:
• Vomitting is not induced
• Gastric lavage not performed to prevent inadvertent aspiration
• Oxygen is given
• Use of Antibiotics and/or corticosteroids is not recomended

17. Loeffler’s syndrome
• Etiology:
• Larva of intestinal parasites
• Drugs: aspirin, penicillin, sulfonamide and imipramine
• Clinical features:
• Cough, low fever and scattered crepitation.
• Treatment: Symptomatic

18. Aspiration pneumonia
• Occurs when food, saliva, liquids, or vomit is breathed
into the lungs or airways leading to the lungs, instead of
being swallowed into the esophagus and stomach.
Symptoms
• Chest pain
• Coughing up foul-smelling, greenish or dark phlegm
(sputum), or phlegm that contains pus or blood
• Fatigue ,fever, SOB,wheezing ,excessive sweating,
breath odour ,difficulty swallowing
• Treatment is supportive.

19. References:
• Nelson’s Textbook of Paediatrics 19th edition.
• OP Ghai and Paul Bagga, Essential Paediatrics 8th
edition
• Medscape

20. Thank you