Pneumonia

 

 

 

 

 

 

 

* Dr Shree Krishna Shrestha, chief consultant pediatrician

 

Definition:   Pneumonia is an infection of Lower Respiratory Tract that involves the airways and parenchyma with consolidation of alveolar spaces

Pneumonitis is a term used for inflammation of lung parenchyma, which may or may not be associated with consolidation

Pneumonia is one of the major cause of death in children.

Risk Factors :

  • Low birth wt/ lack of breastfeeding
  • GE Reflux
  • Aspiration due to any reason
  • Malnutrition/vit A deficiency .
  • Immunocompromised state
  • Anatomic abnormalities of Respiratory tract
  • Hospitalization especially in ICU and following invasive procedures
  • Overcrowding/ air pollution

Classification : Anatomical,

  • Lobar pneumonia – It’s a typical pneumonia localized to one or more lobes of lung (affected lobe is consolidated)
  • Broncho pneumonia – Inflammation of bronchioles / small airways leads to formation of mucopurulent exudate , which causes patchy consolidation of adjacent lobules and obstruction of small airways.
  • Interstitial pneumonia – Inflammation of interstitial tissue ( alveolar sacs and ducts / bronchioles) seen commonly in acute viral infections.
  • Multilobar Pneumonia

Duration  of illness

  • Persistent Pneumonia – persistence of symptoms and radiological abnormalities for more than 4 weeks
  • Recurrent Pneumonia – 2 episodes of pneumonia in 1 yr or >3 episodes any time with X ray clearance in between 2 episodes.

Source of infections :

  • Community Acquired Pneumonia: Acute infection of pulmonary parenchyma in a previously healthy child caused by organisms acquired outside a hospital setting. Patient should not have been hospitalized within 14 days prior to onset of symptoms
  • Hospital Acquired Pneumonia: Infection that was not incubating at the time of hospital admission , is caused by organisms in the hospital and presents 2 or more days after hospitalization

 

  • Opportunistic pneumonia – seen in children with low immunity and caused by atypical organisms

Defence mechanism to prevent pneumonia

  • Cilia on epithelial surfaces move the particles upward into the throat where they are swallowed and coughed out .
  • Reflex broncho construction when a foreign particle is inhaled
  • Airway contaminants are caught in the mucous secreted by goblet cells and mucus is coughed out
  • Polymorphonuclear neutrophils from the blood and tissue macrophages ingest and kill the microorganisms .
  • IGA secreted into the upper airway fluid protects against invasive infections.

Etiology :

Most of the pneumonias are of infective etiology

  • Viral – RSV , Influenza, Para influenza, Adenovirus, Coronavirus

( about 40% of the cases )

  • Bacterial – 40-60% of the cases

Age wise etiological agents

  • 0-2 months age – mainly Gram negative bacteria like – Klebsiella and E. coli . Gram positive like pneumococci and staphylococci.
  • 3 months – 3 years – S.Pneumonia, H.Influenza and staphylococci .
  • 3 years or > 3 years – Pneumococci , Staphylococci.

Gram negative organisms in immunocompromised / severe malnutrition

  • Atypical organisms- Chlamydia and Mycoplasma, Legionella
  • Pneumocystis carnii causes pneumonia in immunocompromised children.
  • Fungi – Histoplasmosis and coccyidiodo mycoses in immunocompromised children

Miscellaneous causes –

  • Ascariasis – Loeffler’s pneumonia
  • Aspiration pneumonia
  • Lipoid pneumonia
  • chemical pneumonia (Kerosene poisoning).
  • 1/3rd of the cases are Idiopathic

Clinical Features:

  • Onset – Insidious starting as URTI or Acute /sudden Symptoms
  • High fever
  • Dyspnoea, cough, chest retractions, grunting
  • Pleuritic chest pain /Abdominal pain
  • Poor feeding, lethargy or malaise
  • Cyanosis, irritability and seizures

On Examination:

  • Tachypneoa
  • Chest retractions – intercostal, subcostal, Nasal flaring
  • Cyanosis
  • Dull note on percussion
  • Auscultation – Rales, wheeze, reduced air entry or bronchial breathing
  • CNS – Altered sensorium, drowsiness, irritability, Menningismus

Main symptoms on viral pnemonia

  • Cold, Cough, wheezing, stridor
  • Fever less prominent
  • CBC – counts normal or mildly elevated with lymphocyte predominance
  • CXR -Diffuse streaky infiltrates (perihilar or peribronchial)
  • Rx – symptomatic – oxygen, nebulisation, hydration, nutrition, paracetamol

Bacterial pnemonia

  • Clinical Symptoms are mainly high fever, chills, cough, dyspnoea
  • Child has toxic look
  • Dull note on percussion
  • Reduced air entry, BB on auscultation
  • CBC -WBC count high >20k, neutrophilic predominance
  • CXR – Lobar consolidation

Streptococcal pneumonia

  • IC 1-3days, abrupt onset
  • High fever , chills ,headache ,cough
  • Differentiating features – cough may be associated with thick, rusty sputum
  • Chest pain
  • Menningismus, convulsions present in Apical Pneumonia
  • CBC –Leucocytosis
  • CXR – Lobar consolidation ( Rt UL consoldn)
  • Blood c/s – positive in 5 to 10% cases
  • Rx – supportive

ABX –  penicillin,  Amoxicillin,  Co amoxiclav

  • Meningitis – Ceftrioxone .
  • Duration 7 to 10days for pneumonia. 

Sthaphylococcal pneumonia

Follows URTI, Pyoderma .

E/O staph infection elsewhere

Progression of symptoms rapid –  lead to

Complications – Empyema

Pyopneumothorax ,Pericarditis, metastatic absecesses in various organs

CXR – Pneumatoceles

Rx – Co amoxiclav /ceftriaxone along with cloxacillin

No response- vancomycin

Duration 7-10days,

empyema, pyothorax 4-6 weeks   

 HIB pneumonia 

  • 3M – 3YR Age grp
  • Insidious onset, begins as URTI/Nasopharyx infection & spreads through bl stream
  • Moderate fever, dyspnoea, chest retractions
  • complications-

Bacteremia, meningitis, empyema

Pericarditis, polyarthritis

  • RX –Ampicillin
  • Cephalosporins – cefotaxime, ceftriaxone 7-10 days

3 weeks in meningitis

Streptococcal (group A, Group B Hemolytic ) pneumonia

  • Generally, occur sec to Measles, varicella, influenza & pertussis
  • More common in newborn

C/F – Abrupt onset

  • Fever, chills, respiratory distress, blood-streaked sputum ,cough
  • Signs are less

Complications – serosanguinous /purulent Empyema

XRAY  – Segmental involvement

  • Diffuse peribronchial densities
  • Parapneumonic effusion
  • Pneumatoceles may be present

Rx – Penicillin G , Ampicillin 7-10 days

Empyema- ICD 

Primary atypical pneumonia

  • Mycoplasma, Chlamydia, Legionella
  • Age grp – Mycoplasma >4yrs Age grp

Chlamydia and Legionella – all Age grps

  • Pathology- Interistitial Pneumonia
  • C/F – onset can be Insidious or Acute
  • Fever, sore throat, cough, myalgia,headache. Blood-streaked sputum
  • sometimes Dyspnoea, chest retractions rare
  • Signs – pharyngitis, cervical lymphadenopathy, hemolytic anemia
  • CXR – Hazy fluffy exudates radiating frm hilar region

Pleural effusion usually involving lower lobes

  • Rx – Macrolides – Erythromycin/Azithromycin/ Clarithromycin

      Pneumonia with gram negative bacteria

  • coli, Klebsiella, Pseudomonas
  • Most common in newborns and infants <2mon Age
  • Older children- Malnutrition or immunodeficiency setting
  • Pseudomonas Pneumonia- Cystic Fibrosis
  • C/F – Gradual onset, can have a life threatening course

Constitutional symptoms are more prominent than respiratory distress. Signs   of                           consolidation are minimal in infants

  • CXR – Massive Consolidation

E.Coli ,Klebsiella Pneumonia- Pneumatoceles may be seen

Diagnosis – ELISA IgM IgG/ PCR Pharyngeal swab or sputum – mycoplasma

  • Rx – IV 3rd generation cephalosporins- ceftrioxone /cefotaxime with or without Aminoglycosides

Pseudomonas- ceftazidime 7- 10days

Evaluation and investigation

  • BLOOD – CBC, CRP , Blood C/S, Serology /PCR
  • (R/O TB & viral / atypical pneumonia)
  • CXR – consolidation, Effusion, Pneumatoceles
  • SPUTUM /Nasopharyngeal aspirate – Gram staining , viral Ag detection
  • PLEURAL FLUID ANALYSIS – R/o TB
  • INVASIVE – Bronchoscopy, BAL analysis

Complications :  

  • Empyema / Pyopneumothorax
  • Sepsis / bacteremia- metastatic septic lesions
  • Pericardial effusion
  • Lung Abscess
  • Parapneumonic Effusion
  • Respiratory Failure

Management :

Supportive care

  • O2 inhalation
  • Nebulisation
  • Antipyretics
  • Hydration
  • Nutrition
  • Chest physiotherapy

ANTIBIOTICS – choice based on organism.

  • Amoxycillin 1st line in community acquired pneumonia in a stable child
  • Penicillin G, cephalosporins
  • Macrolides in Atypical Pneumonia

Viral – supportive /symptomatic Rx

Rx – of complications 

Prevention :

  • Immunization
  • Hand hygiene
  • Wearing masks
  • Zinc supplementation
  • Prompt and early treatment with ABX can reduce the requirement /duration of mechanical ventilation and therefore prevent nosocomial pneumonias
  • Hospital staff with resp illness or who are carriers should not be assigned patient care duties

Prognosis:

  •  Most children recover rapidly and completely
  • Radiographic abnormalities may take 6-8 weeks to return to normal
  • Few cases pneumonia may be persistent or reccurent.

In such cases diagnosis must be reviewed further to R/O conditions such as TB, Cystic fibrosis, immunodeficiencies, FB , GERD or anatomical abnormalities of lung.

Stratigy :

1.To ensure standard care management of pneumonia in children under 5yrs by training medical and other health personnel

  1. To train peripheral health staff to recognize and treat cases of pneumonia along with timely referral in case of severe pneumonia
  2. To improve maternal knowledge about home management of cough cold and recognition of early danger signs for seeking appropriate care
  3. To promote immunizations , exclusive breastfeeding in the first 6mon , introducing timely complimentary food, and vit A administration

Prevention :

  1. Improving primary medical care services and developing better methods for early detection, treatment and prevention of ARI
  2. Mortality rate due to pneumonia is reduced if treated correctly
  3. Feeding children with adequate amounts of varied nutrition to keep their immune system strong

4 Immunization – measles vaccine, Hib vaccine, pneumococcal vaccine

Global action plan for pneumonia:

  • Integrated global action plan for prevention and control of pneumonia and diarrhoea
  • Was released by WHO & UNICEF in 2013

Goals

To end preventable childhood deaths due to pneumonia and diarrhoea by 2025

Objectives

  • Protect children with good health practices from birth
  • Breast feeding exclusively for 6 months
  • Provide adequate complementary feeding
  • Supplement diet with nutritients like vitaminA

Conclusions:

Active interventions and steps to manage complications should be taken to reduce <5yr mortality and morbidity

Prevention

  • Immunization
  • Hand washing/ hygiene measures
  • Improve access to safe drinking water and sanitation
  • Reduce household air pollution
  • HIV prevention
  • Provide cotrimoxazole prophylaxis for HIV – infected and exposed children

Treat children who are ill –

  • Improved ealth care and referral to health facilities
  • Leverage case management at the health facility & community levels
  • Use AMOXICILLIN and oxygen to treat pneumonia, low osmolarity , ORS and Zinc to treat diarrhoea . Continue feeding  including breast feeding.

*Dr Shrestha worked at Pokhara Academy of health sciences as a dean.  (shreekrishnas@gmail.com)