Journal: SunText Review of Pediatric Care
DOI: 10.51737/2766-5216.2022.030
Download PDFPneumonia
is the leading infectious and preventable cause of death in under five
children. It can be caused by viruses, bacteria or fungi. It can be prevented
by immunization, adequate nutrition and improving environmental factors. Its
incidence can be reduced by simple interventions, and treated with low-cost,
low-tech medication and care including antibiotics for bacterial cause and
other symptomatic relief.
Infectious diseases remain a leading cause
of underfive deaths. Lower respiratory infections (18·7%), diarrhea (15·7%),
malaria (15·8%) comprise the leading causes of under-five deaths globally among
children aged 1 to 59 mo [1]. India accounted for 783,314 under five deaths in
2020 with mortality rate of 33 deaths per 1000 live births [2]. Killing more
than 14 children every hour of pneumonia, 126,535 children in 2018 [3].
Pneumonia is classified as [4]
1. Community
acquired pneumonia (CAP) – acquired outside the hospital environment in a
previously healthy immune competent subject. The patient should not have been
hospitalized within 14 days prior to the onset of symptoms.
2. Nosocomial pneumonia - pneumonia acquired within
hospital setting more than 48 hours after hospitalization [hospital-acquired
pneumonia (HAP)] or more than 48 to 72 hours after endotracheal intubation
[ventilator associated pneumonia (VAP)].
3. Recurrent
Pneumonia – two episodes of pneumonia in 1 year or 3 episodes in any time
frame.
4. Aspiration
Pneumonia – due to aspiration of foreign materials in the lower airways.
The
pneumonia is caused by several microorganisms including bacteria, virus,
mycoplasma and fungi [5]. The etiology of pneumonia differs age wise. Pneumonia
in less than 3 mo is commonly caused by gram negative bacteria. Between 3 mo of
age to 5 y of age, besides viruses, the common bacterial organisms are gram
positive organisms like streptococcus pneumonia (most common), Haemophilus
influenzae (in up to 2 y of age), Staphylococcus aureus (relatively less
common). For more than 5 years, common organisms are Streptococcus pneumonia,
Mycoplasma pneumonia and Staphylococcus aureus. Cause of pneumonia in
immunocompromised children especially those living with HIV is commonly
Pneumocystis jiroveci [6-8].
In
India, Respiratory syncytial virus (24.1%) is the most common pathogens
identified from children with CAP and among bacterial causes S. pneumoniae is
most common organism (5.7%) followed by M. pneumoniae (4.3%) and H. influenzae
(0.8%) [9].
Different
organisms show different pathologic patterns of lung involvement.Viral
infection can occur in three pathologic patterns as bronchiolitis, interstitial
pneumonia, and parenchymal infection. Its characteristic features are
neutrophilic infiltration in the lumen of the airway with lymphocytic infiltration
of the interstitial and parenchyma of the lungs. Histologically, giant cell
formation and viral inclusion within the nucleus of the respiratory cells leads
to injury of the respiratory epithelium in form of swelling, abnormal secretion
and cellular debris which results in air trapping due to obstructed or
obliterated small airways and thickened septa, causing ventilation-perfusion
mismatch ultimately leading to atelectasis, interstitial edema, and hypoxemia. Bacterial
infection can occur in five pathologic patterns as lobar pneumonia (e.g., S.
pneumoniae); bronchopneumonia (e.g., S. pyogenes and S. pneumoniae);
necrotizing parenchymal pneumonia (e.g., S. aureus and S. pneumoniae);
caseating granulomatous disease (e.g., M. tuberculosis); and peri-bronchial and
interstitial disease with secondary parenchymal infiltration, which usually
occurs when viral pneumonia is complicated by bacterial infection.
Lobar
pneumonia can be differentiated from bronchopneumonia as former show
parenchymal infection, inflammation, and consolidation of a lobe or a segment
of a lobe whereas later show primary infection of the airways and surrounding
interstitium.
Symptoms
of viral and bacterial pneumonia are similar. However, viral pneumonia may have
more numerous symptoms than bacterial. Symptoms of pneumonia include fever,
tachypnea (WHO defines tachypnea according to age as: <2 mo: >60
breaths/min; 2 to 12 mo: >50 breaths/min; >1 to 5 y: >40 breaths/min;
?5 y: >20 breaths/min), lower chest wall indrawing (retractions), nasal
flaring and use of accessory muscles. Severely ill child may have cyanosis,
poor feeding, unable to drink, vomiting, unconsciousness, hypothermia and
convulsions.
Signs
of pneumonia include rhonchi, scattered crackles, and diminished breath sounds.
Other signs may also be present like wheezing (more common in viral
infections), abdomen distention (from swallowed air), abdomen pain (common in
lower lobe pneumonia), liver seemed enlarged (as of downward displacement).
Most
healthy children can fight the infection with their natural defences but there
are factors that affect incidence in the community in developing countries.
They can be divided as definite, likely or possible causes [15]. Definite
causes include lack of immunization (especially diphtheria, pertussis,
pneumonia, measles, polio, BCG, influenza), malnutrition, low birth weight
(?2500gm), non-exclusive breastfeeding (during the first 4 months of life), air
pollution, and crowding. Likely or possible causes may include parental
smoking, zinc deficiency, mother's experience as a care giver and education,
concomitant diseases (e.g., diarrhea, heart disease, asthma), and vitamin A
deficiency,
Include
pleural effusion and empyema, lung abscess, bronchopleural fistula, necrotizing
pneumonia, acute respiratory distress syndrome (ARDS), extrapulmonary infection
(meningitis, arthritis, pericarditis, osteomyelitis, and endocarditis),
hemolytic uremic syndrome, and sepsis.
The
diagnosis of pneumonia can be made by proper history and physical examination.
The clinical setting and the severity of the illness define the diagnostic
approach. The diagnosis of pneumonia is considered in infants and children who
present with respiratory complaints viz cough, tachypnea, retractions, and
abnormal lung examination in community practice in doubt diagnosis can be
confirmed on chest radiographs or lung ultrasonography [16]. The peripheral
white blood cell (WBC) count can differentiate viral from bacterial pneumonia
i.e. in viral pneumonia it is normal or elevated (<20,000/mm3) with a
lymphocyte predominance in contrast in bacterial pneumonia it is elevated
(15,000-40,000/mm3) with a granulocyte predominance [7].
WHO (2014) recommend management of pneumonia by classifying into three categories:
The
WHO advise for children age 2-59 mo as observation for 5 d in home care under
category “no pneumonia” and for category “pneumonia” domiciliary treatment
including oral amoxicillin, at least 40mg/kg/dose twice daily for 5 d with a
follow up on 3rd d. Symptomatic relief include soothing the throat and
relieving the cough with a safe remedy. If wheezing present (or disappeared
after rapidly acting bronchodilator), give an inhaled bronchodilator for 5 d
(if not available oral salbutamol may be tried). If coughing for more than 14 d
or recurrent wheeze, refer for possible TB or asthma assessment. Advise mother
about danger signs so as when to return immediately. Child failing the
first-line treatment by 3rd d should be referred to facility equipped with
appropriate second line treatment i.e. parental. In areas with low HIV
prevalence treatment is given for 3 d, if chest in drawing is not present.
Similarly, child with category “severe pneumonia” is treated with parenteral
ampicillin (50mg/kg), or benzyl penicillin (50,000 units/kg) IM/IV every 6 h and
gentamicin (7.5 mg/kg IM/IV once a day) for at least 5 d as first line drugs.
Ceftriaxone should be used as second line drug. In HIV-infected and -exposed
infants and children with chest in drawing or severe pneumonia, the first line
is ampicillin/penicillin plus gentamicin or ceftriaxone, whereas second line is
ceftriaxone alone. For suspected Pneumocystis jiroveci pneumonia (PCP) aged
from 2 mo up to 1y additional cotrimoxazole should be given empirically [14].
There are other alternative antibiotics like co-amoxyclav, cefpodoxime,
cefaclor, erythromycin, azithromycin, clarithromycin, chloramphenicol and
levofloxacin can be used for pneumonia [17]. In a recent study conducted at
tertiary care centre double-blind randomized controlled trial compared cure
rate with 5 d oral amoxicillin vs amoxicillin plus clavulanic acid in children
aged 6 to 36 mo with CAP, presenting with the clinical features consistent with
the diagnosis of CAP. Patients were
given oral Amoxicillin or Amoxycillin plus Clavulanic Acid for 5 d and followed
at 48h, 5th d and 2 mo.The cure rate of CAP in amoxicillin plus clavulanic acid
group was significantly higher as compared to amoxicillin group (93.88% vs
79.17%, p 0.013). The chances of cure rate increased by 15.3% for children receiving
oral amoxicillin plus clavulanic acid. Only mild side effects like diarrhea
(22.1%), nausea (9.6%), vomiting (5.7%), and maculo-papular rash (2.9%) were
found in both groups. All the cured children were followed up to 2 mo and none
of the children had recurrence. These findings suggest that amoxicillin plus
clavulanic acid be used in the WHO treatment plan for community acquired
pneumonia.
I
am indebted to Prof K N Agarwal for valuable suggestions.