community acquired pneumonia

1. COMMUNITY ACQUIRED
PNEUMONIA

3. • Acute infection of lung parenchyma in previously healthy child, acquired
outside of the hospital settings, and not hospitalized within 14 days prior to
onset of symptoms. This excludes children with immunodeficiency, severe
malnutrition, and post measles state.

4. EPIDEMIOLOGY
Pneumonia
• Inflammation of the
lung parenchyma
• leading infectious
cause of death globally
among children younger
than 5 year old

5. ETIOLOGY
•Non infectious causes: include aspiration (of food or gastric acid,
foreign bodies, hydrocarbons, and lipoid substances)
•Microorganisms
•Hypersensitivity reactions,
•Drug- or radiation-induced pneumonitis

6. ETIOLOGY: Infectious Causes
•Streptococcus pneumoniae
 most common bacterial pathogen in children 3 weeks to 4 years of
age
•Mycoplasma pneumoniae and Chlamydophila pneumoniae
 Most frequent bacterial pathogens in children age 5 years and
older
•Group A streptococcus
•Staphylococcus aureus
 Often complicates an illness caused by influenza viruses.

10. ETIOLOGY
•Viral pathogens are the most common causes of lower respiratory
tract infections in infants and children older than 1 month but younger
than 5 years of age.
•Respiratory syncytial virus and rhinoviruses
 Most Common identified especially in children younger than 2 yr
of age.

12. PATHOGENESIS: Viral pneumonia
•Spread of infection along the airways
•Direct injury of the respiratory epithelium
•Airway obstruction from swelling, abnormal secretions, and cellular debris.
•Atelectasis, interstitial edema, and hypoxemia from ventilation perfusion
mismatch often accompany airway obstruction.
 Viral infection of the respiratory tract can also predispose to secondary
bacterial infection by disturbing normal host defense mechanisms, altering
secretions, and through disruptions in the respiratory microbiota.

13. PATHOGENESIS: Bacterial pneumonia
•Respiratory tract organisms colonize the trachea and subsequently
gain access to the lungs
•pneumonia may also result from direct seeding of lung tissue after
bacteremia
•Bacterial infection is established in the lung parenchyma, the
pathologic process varies according to the invading organism.

14. M. pneumoniae
• Attaches to the respiratory epithelium, inhibits ciliary action, and leads to
cellular destruction and an inflammatory response in the submucosa.
•As the infection progresses, sloughed cellular debris, inflammatory cells,
and mucus cause airway obstruction, with spread of infection occurring
along the bronchial tree, as is seen in viral pneumonia.
S. pneumoniae
•produces local edema that aids in the proliferation of organisms and their
spread into adjacent portions of lung resulting in the characteristic focal
lobar involvement

15. Group A streptococcus
•typically results in more diffuse lung involvement with interstitial pneumonia.
•necrosis of tracheobronchial mucosa; formation of large amounts of exudate,
edema, and local hemorrhage, with extension into the interalveolar septa; and
involvement of lymphatic vessels with frequent pleural involvement
S. aureus
•confluent bronchopneumonia unilateral and characterized by the presence of
extensive areas of hemorrhagic necrosis and irregular areas of cavitation of the
lung parenchyma
•resulting in pneumatoceles, empyema, and, at times, bronchopulmonary
fistulas

16. PATHOGENESIS:
Recurrent Pneumonia
•Defined as 2 or more
episodes in a single year or 3
or more episodes ever, with
radiographic clearing between
occurrences
•An underlying disorder
should be considered if a
child experiences recurrent
pneumonia

17. Clinical Manifestation
•Pneumonia is frequently preceded by several days of symptoms of an
upper respiratory tract infection, typically rhinitis and cough.
•In viral pneumonia fever is present but lower than bacterial pneumonia
•Tachypnea is the most consistent clinical manifestation of pneumonia.
•Increased work of breathing accompanied by intercostal, subcostal, and
suprasternal retractions, nasal flaring, and use of accessory muscles is
common.

18. •Severe infection may be accompanied by cyanosis and lethargy,
especially in infants.
•Auscultation of the chest may reveal crackles and wheezing, but it is
often difficult to localize the source of these adventitious sounds in very
young children with hyperresonant chests.
•In many children, splinting on the affected side to minimize pleuritic
pain and improve ventilation is noted; such children may lie on one side
with the knees drawn up to the chest.

19. •Early in the course of illness, diminished breath sounds, scattered crackles, and
rhonchi are commonly heard over the affected lung field
•With the development of increasing consolidation or complications of pneumonia
such as pleural effusion or empyema, dullness on percussion is noted and breath
sounds may be diminished
•A lag in respiratory excursion often occurs on the affected side
•Abdominal distention may be prominent because of gastric dilation from swallowed
air or ileus
•The liver may seem enlarged because of downward displacement of the diaphragm
secondary to hyperinflation of the lungs or superimposed congestive heart failure

20. •In infants, there may be a prodrome of upper respiratory tract infection and poor
feeding, leading to the abrupt onset of fever, restlessness, apprehension, and
respiratory distress.
•These infants typically appear ill, with respiratory distress manifested as
grunting; nasal flaring; retractions of the supraclavicular, intercostal, and subcostal
areas; tachypnea; tachycardia; air hunger; and often cyanosis
•Some infants with bacterial pneumonia may have associated gastrointestinal
disturbances characterized by vomiting, anorexia, diarrhea, and abdominal
distention secondary to a paralytic ileus.

24. Community-acquired pneumonia (CAP) is a clinical diagnosis and no
investigations are required in outpatient department (OPD) setting.
Investigations required in hospitalized children—complete blood count (CBC),
blood culture, chest X-ray, inflammatory markers [C-reactive protein (CRP) and
procalcitonin], and molecular methods [multiplex reverse transcription–
polymerase chain reaction (RTPCR) and BioFire).
A combination of CRP, procalcitonin, and CBC—better understanding the
response to the treatment.

25. Isotype enzyme-linked immunosorbent assay (ELISA) for antibody
detection against Mycoplasma—better than cold agglutinins.
Pulse oximetry is helpful in assessing the severity and monitoring
response to treatment in hospitalized children or those with severe
disease.

31. Macrolides in CAP (used in following situations):
In a child immunized against Hemophilus influenzae type b
(Hib)/pneumococcal conjugate vaccine (PCV): If no response to first-line
antibiotics or suppurative complications of CAP are absent.
Persistence of the following: Low-grade fever, cough, few clinical signs, and
chest X-ray showing bilateral perihilar streaky infiltrates.
Extrapulmonary manifestations not suggestive of Staphylococcus aureus
or no response to antistaphylococcal antibiotics.

32. Only symptomatic and supportive treatment
Oseltamivir can be given if H1N1 infection is suspected but that should
be initiated within 3 days of symptoms. The details of dose schedule are
provided in Table [recommended by the American Academy of
Pediatrics (AAP) and Centers for Disease Control and Prevention
(CDC)].

34. COMPLICATIONS
•are usually the result of direct spread of bacterial infection within the
thoracic cavity (pleural effusion, empyema, and pericarditis) or
bacteremia and hematologic spread.
•Meningitis, suppurative arthritis, and osteomyelitis
 rare complications of hematologic spread of pneumococcal or H.
influenzae type b infection.
Parapneumonic effusions and empyema
• S. aureus, S. pneumoniae, and S. pyogenes are the most common
causes
• Imaging studies including ultrasonography and CT are helpful in
determining the stage of empyema.
•The mainstays of therapy include antibiotic therapy and drainage with
tube thoracostomy.

35. PREVENTION
•13-valent pneumococcal conjugate vaccine (PCV13)
•The expansion of influenza vaccine recommendations to include all
children >6 mo of age in 2010 might be expected to affect pneumonia
hospitalization rates in a similar fashion, and ongoing surveillance is
warranted.

36. THANK YOU