Pneumonia is a leading cause of death in children under 5 years old worldwide. Fast breathing in a child presenting with cough or difficulty breathing is highly sensitive and specific for diagnosing pneumonia. Common causative agents are Streptococcus pneumoniae, Haemophilus influenzae, and Mycoplasma pneumoniae. Treatment involves antibiotics like co-trimoxazole, but cough mixtures are ineffective and potentially harmful. Prevention through vaccination against Hib can significantly reduce risk of serious infection.
Overview of pneumonia's historical context, disease pattern, and epidemiological data, highlighting acute respiratory infections affecting children under 5.
Risk factors for pneumonia in children, including age, parental education, and health history, and types of pneumonia - CAP vs. nosocomial.
Clinical signs and symptoms of pneumonia, comparing diagnostic methods and laboratory evaluations for identifying pneumonia in children.
Impact of Vitamin A and Zinc supplementation on respiratory diseases, with study data on effects of deficiencies and supplementation.
Formulations and categories of cough mixtures, efficacy concerns, and treatment guidelines for pneumonia in children.
Common bacterial pathogens in pneumonia, their virulence factors, integrated management for childhood illnesses and preventive strategies.
Detailed analysis of Haemophilus influenzae and Mycoplasma pneumoniae virulence, pathogenesis, and the role of immune response during infections.
Epidemiology
•Each year, acuterespiratory infections
cause approximately 2-3 million deaths
among children <5 years old and are the
leading cause of death in this age group.
•About 1% of pneumonia cases result in
sequelae (e.g., bronchiectasis)
4.
• Identifying thecause of community-
acquired pneumonia is more difficult in
children
5.
Number of PneumoniaEpisodes Per
Year in Childeren Under 5 Years
Place Annual Incidence per 100
Seattle (USA) 3.0
Gadchiorili (India) 13.0
Bankok (Thailand) 7.0
Nepal 16.5
Egypt ???
6.
Epidemiology
•A lower respiratorytract infection (LRI)
develops in one in three children in the first
year of life.
•Twenty-nine percent of these children
develop pneumonia
•Approximately 10-20% of all children <5
years old in developing countries develop
pneumonia each year
7.
Risk Factors
• Significantrisk factors were younger age (2-
6 months), low parental education, smoking
at home, prematurity, weaning from breast
milk at < 6 months, a negative history of
diphtheria, pertussis and tetanus
vaccination, anaemia and malnutrition.
• Trop Doct 2001 Jul;31(3):139-41
Types of Pneumonia
•Currentlypneumonias are defined as
either community-acquired (CAP) or
nosocomial or hospital-acquired .
•CAP is defined as an infection
acquired in the community setting;
the definition varies and it may or
may not include infections acquired
in a nursing home or long-term care
facility
10.
Aetiological agents
•The exactincidence varies but in a
meta-analysis of 122 cases of CAP, it
accounted for 66% of cases in which
a microbiological diagnosis was
made.
•Exact incidences of the various
aetiologic organisms are not
known.
Comparison of Methodsfor the
Detection of Pneumonia in Children
Method Sensitivity Specificity
Stethoscope 53% 59%
(crepetations)
Simple clinical signs 77% 58%
(fast breathing or
chest indrawing)
Note: Pneumonia diagnosis confirmed by Chest X-ray
Epidemiology,Clinical,and Laboratory Featuresof
Acute Pneumonia in Normal Infants and Children
According to Etiologic Agents
Bacteria Virus Mycoplasma
Historical clues
- Age Any,esp.infant Any School
age,adolescent
- Temp. Majority ≥ 39° C < 39° C Majority < 39° C
- Onset Abrupt Gradually
worsening URI
Gradually
worsening cough
- Others in home ill Infrequent Frequent Frequent,wk.apart
- Ass. Signs,
symptom
Meningitis,otitis,
arthritis
Myalgia,rash,co
njunctivitis
Headache, sore
throat, myalgia
- Cough Productive Nonproductive Hacking
- Pleuritic chest
pain
Frequent Infrequent Infrequent
17.
Diagnosis
•Recent studies haveconcluded
that generally radiology is not
helpful for determining the
aetiology of the infection.
•The diagnosis of pneumonia is
based on a history of respiratory
tract infection and the
radiological finding of new
pulmonary infiltrates
18.
Clinical Diagnosis
• Tachypnoeaaccording to the usual
WHO criteria.
• Auscultatory signs have lower
specificity.
• Acute phase reactants cannot be relied
for aetiological diagnosis.
• Blood culture positivity in only <10%
• Viral antigen detection not available.
19.
Pneumonia and VitaminA
•Weekly low-dose (10 000 IU) vitamin A
supplementation in a region of
subclinical deficiency protected
underweight children from ALRI and
paradoxically increased ALRI in
normal children with body weight
over -1 SD in Ecuadorian Children .
•Large doses of vitamin A had no
protective effect on the course of
pneumonia in hospitalized Tanzanian
children.
20.
Pneumonia and Zinc
Reductionin all respiratory diseases.
(Indian J Pediatr 1995; 62,181-93
2.5 fold decrease in respiratory infection.
(Am J Clin Nutr; 1996; 63; 514-9
Significant reduction in upper respiratory tract
disease.
(Am J Clin. Nutr. 1996; 63;514-9)
Reduction of 45% incidence of lower respiratory
tract infection.
(PEDIATRICS 1998; 102 ;1-5)
21.
Compositions of coughmixtures
available
Category
A - Only Antitussive F - Expectorant + Antitussive
B - Only expectorant G - Expectorant + Bronchodilator
C - Only mucolytics H - Expectorant + Mucolytics
D - Only bronchodilator I - Expectorant + Antihistamines
E - Only Antihistamine J - Having more than 2 of the
A,B,C,D,E.
K - Bronchodilator + Antihistamine
22.
Formulations available
Type ofFormulation
Tablets/capsules 19 23.75%
Liquid/Syrups 56 70.00%
Other forms 5 6.25%
TOTAL 80 100%
Over the countercough mixtures
• No well-controlled studies supporting the use of codeine or
dextromethorphan as antitussives for children have been
published, and indications for their use have not been
established.
• Cough due to URTI can often be treated with non-drug
measures (fluids and humidity).
• Pediatric dosages of antitussives are extrapolated from
adult data and thus are imprecise for children.
• Significant adverse effects of their use have been
documented.
• Clinicians should tell parents and patients about these
concerns.
25.
Systematic review ofrandomised controlled trials of over the
counter cough medicines for acute cough in adults
BMJ 2002;324:329 ( 9 February )
• Conclusion: Over the counter cough
medicines for acute cough cannot be
recommended because there is no good
evidence for their effectiveness. Even when
trials had significant results, the effect sizes
were small and of doubtful clinical
relevance. Because of the small number of
trials in each category, the results have to be
interpreted cautiously.
26.
•Treatment must assessthe severity of the
illness, appropriate setting for treatment
(outpatient vs. inpatient), socioeconomic
conditions, and local susceptibility
patterns of common pathogens.
Treatment
•Various guidelines have been developed.
•Once treatment has begun, no change
in medication is indicated within the 1st
72 hours unless a specific organism is
identified and is not covered by the
current medication .
27.
Causative Agents
• InAfrica and South America (8 studies),
bacteria were recovered from 56% (range
32%-68%) of severely ill children studied
by lung aspirate. The most often isolated
bacteria were Streptococcus pneumoniae
(33%) and Haemophilus influenzae (21%)
– Braz J Infect Dis 2001 Apr;5(2):87-97
28.
Haemophilus influenzae
•polyribosyl ribitolphosphate (PRP) capsule
is an important virulence factor which
renders type b H. influenzae resistant to
phagocytosis by PMNs in the absence of
specific anticapsular antibody .
•produce IgA protease which may
facilitate attachment to mucosal surfaces
•treatment with a combination of
amoxicillin and clavulanic acid
(Augmentin) or TMP/SMX is effective
against þ-lactamase-producing strains
29.
Streptococcus pneumoniae
•Ccapsular polysaccharideis most
important virulence factor;
approximately 85 capsular types
•Penicillin is drug of choice for
susceptible organisms (MIC =
0.06 µg/mL) .
•Vaccine contains 23 most
common capsular serotypes
30.
Mycoplasma pneumoniae
•special attachmentorganelle; attach to
epithelium via protein adhesins on the
attachment organelle; major adhesin is a
170-kilodalton (kDa) protein, named P1
•bacteria injure mucosa by producing
oxidants (hydrogen peroxide &
superoxide radicals) which cause
ciliostasis and epithelial necrosis thus
inhibiting normal clearance mechanisms
31.
Integrated Management ofChildhood
Illnesses
Does the child have cough or difficulty in breathing?
If Yes Ask: Signs Clsssify as
For How Long? Any general danger sign or Severe
Chest indrawing or pneumonia
Stridor
Look, Listen Fast breathing Pneumonia
Count the breaths
Chest indrawing No signs of pneumonia No Pneumonia:
Stridor or very severe disease cough or cold
32.
Suggested Drug Treatment
•Birth to 20 days:
Admission
• 3 weeks to 3 months:
– Afebrile: oral
erythromycin
– Febrile: add cefotaxime
• 4 months to 5 years:
Amoxycillin
80mg/kg/dose
• 6-14 years:
Erythromycin
NEJM Volume 346:429-437
33.
Prevention
• Within twoyears of the introduction of routine
Hib vaccination of infants in the UK, the risk of
serious Hib infection had fallen from 1:600 to
1:30,000 by 5 years of age
Eur J Clin Microbiol Infect Dis 1995
Nov;14(11):935-48
• It is important that these highly effective vaccines
should be made available to children in the
developing countries.
Acta Paediatr 2001 May;90(5):473-6
34.
Summary
Pneumonia in childrenin the age group
of 2 months to 5 years
•Pneumonia is the commonest cause of mortality
•Fast breathing in a child with cough or difficulty
breathing is highly sensitive and specific for diagnosis
•Co-trimoxazole is the effective treatment for
community pneumonia in children
•Cough mixtures are not useful but harmful.
•Cough persists for few weeks.
35.
Haemophilus influenzae
•Strains areclassified as either
serotypable (if they display a capsular
polysaccharide antigen) or nontypable
(no capsule); seven generally
recognized serotypes: a, b, c, d, e, e'
and f; H. influenzae type b (Hib) is the
most virulent
•Nontypable H. influenzae strains
colonize the nasopharynx of most
normal children.
36.
Haemophilus influenzae
•Approximately 20-30%of isolates
are beta-lactamse positive.
•Treatment with either
amoxicillin/clavulanic acid or
TMP/SMX is effective against þ-
lactamase-producing strains.
37.
Mycoplasma pneumoniae
•Data suggestthat repeated infections
are required before symptomatic
disease occurs - antibodies to M.
pneumoniae can be found in most
children age 2 - 5 years while illness
occurs with greater frequency among
older children and young adults .
•Resistant to antibiotics that inhibit
bacterial cell wall synthesis (e.g.,
penicillin, cephalosporins, vancomycin)
38.
Structure, Virulence Factorsand
Pathogenesis
•encapsulated organisms can
penetrate the epithelium of the
nasopharynx and invade blood
capillaries directly; nontypable strains
are less invasive, but they, as well as
typable strains, induce an
inflammatory response that causes
disease
39.
Mycoplasma pneumoniae
•M. pneumoniaeacts as a superantigen
(macrophage activation, cytokine
induction) and stimulates inflammation;
pneumonia is induced largely by local
immunologic and phagocytic responses
to the parasites.
•some children may develop cold
agglutinins as a result of infection.
40.
Structure, Virulence Factorsand
Pathogenesis
•Secretory IgA protease - inhibits
function of secretory IgA which
normally binds bacteria to mucin to
facilitate clearance from the
respiratory tract
•Pneumolysin - creates pores in and
destroys ciliated epithelial cells
•Hydrogen peroxide - reactive 02
intermediate causes tissue damage