Pediatric Respiratory Disorders😊

Initial Presentation

• First wheezing episode in infants.

Epidemiology

• Most common infection in children aged 1–6 months.

• Rare after 2 years of age.

Etiology

• Most common cause: Respiratory Syncytial Virus (RSV).
• Season: Rainy season
• Infants → M/c/c of LRTI
• Adults → causes URTI
• Microscopy: Syncytial (multinuclear) appearance

• Causes inflammation and narrowing of small airways.

Clinical Presentation

• Preceded by respiratory illness in a family member.

• Symptoms:
• Rhinorrhea
• Cough
• Dyspnea
• Sneezing

Radiographic Findings

• Chest X-ray:
• Hyperinflation
• Patchy atelectasis

Treatment Specifics

Oxygenation & Hydration

• Provide oxygen support
• High-flow oxygen via nasal cannula.
• Target SpO₂ > 90%

• Ensure good hydration

Antiviral Therapy in Bronchiolitis

• Nebulized ribavirin:
• Controversial in high-risk cases (Nelson).
• Indicated if co-associated with:
• Congenital heart disease
• Chronic lung disease
• Immune deficiency

Severe Bronchiolitis

• Seen in :
• Premature infants
• Early age of onset
• Presence of comorbidities

Prophylaxis in Bronchiolitis

• I.M. Palivizumab indicated for:
• Act on F protein of RSV
• Children born < 29 weeks gestation
• Significant congenital heart disease
• Chronic lung disease of prematurity
• Immune deficiency
• Neuromuscular disease

• M/c congenital disorder of larynx

• Definition
• Excessive flaccidity of the epiglottis or supraglottis
• Due to immature cartilage, which matures with age

Important: Only inspiratory stridor present

• Most common cause of stridor in infants.

Stridor

• Stridor may develop from 2 to 4 weeks.

Flexible laryngoscopy

• Omega-shaped epiglottis

• Loose and floppy

• Curled upon itself

Treatment

• Self-limiting disorder.

• Wait and watch until epiglottis matures

• Reassurance, Posture repositioning

• Epiglottopexy → surgery for severe stridor

• If progressive respiratory distress (15-20%)
• Supraglottoplasty

For a 3-week-old baby suffering from a cough and sore throat, where the mother states that the baby experiences a sudden bout of coughing followed by temporary cessation of breathing, with a total leukocyte count exceeding 50,000 cells per microliter, which medication would you recommend for this patient?

• Bordetella pertussis (also known as the 100-day cough)

• Toxin - PT (↑↑ CAMP)

• Disease: Whooping cough/pertussis

• Common in: Infants, especially unvaccinated

Phases of Whooping Cough

Diagnostic Criteria

• Suspect if cough ≥14 days with no other cause + any of:
• Paroxysmal cough
• Worse at night, after feeding
• Inspiratory whoop
• Post-tussive vomiting
• Central cyanosis
• Undiagnosed apnoeic attacks (infants)
• May cause syncope/seizures from anoxia

• Marked lymphocytosis also seen

Investigations

• PCR (1st line):
• Best in first 3 weeks
• Fast and sensitive

• Swab type:
• Pernasal → infants/young children
• Nasopharyngeal → older children/adults

Characteristics

• Bordet - Gengou medium/ Regan Lowe
• Bisected pearls/mercury drops
• Aluminum paint appearance (confluent)

• M/E: thumb print appearance

• Boarderil gengiwar→ camp ketti→ 100 days war → they used mercury and aluminium paint for war

• Board il mercury drops- fuse to form aluminium paint- make thumb print out of it

• Drug of Choice:
• Macrolides (within 21 days of onset):
• Erythromycin > Azithromycin > Clarithromycin
• Admit infants <6 months

• Prevention: Acellular vaccine
• FHA, PT, AGG, PERT
• No complication

Complications

• Subconjunctival hemorrhage

• Pneumonia

• Bronchiectasis

• Seizures

Genetics:

• Gene for atopy: Chromosome 5q gene Polymorphism

• At birth → TH2 Phenotype
• Normally
• switch to TH1 phenotype
• due to exposure to many outdoor antigens
• TH1 phenotype → Asthma disappears.
• No exposure to allergens
• Persistence of TH2 phenotype.
• Persistence of TH2 phenotype → Asthma persists.

• Associations: 
• IL-13, ADAM33 gene polymorphisms.
• Note: mutation of ADAMTS-13: TTP

• Type 1 hypersensitivity (allergic) reaction.

• IL-5 → Eosinophil mediated Pathology.

Features of Asthma:

• Type I Respiratory Failure:
• No CO2 retention seen.
• No Type II respiratory failure.

• No parenchymal involvement.

• No diffusion defect.
• Normal to ↑ DLCO.

Sputum Microscopy (The Three C's):

• Charcot-Leyden crystals:
• Needle-shaped crystals made of galectin-10
• derived from eosinophils.
• Eda charley, needle vach easy aytt kalakku

• Creola bodies:
• Clusters of epithelial cells.
• Sloughed mucus epithelium.

• Curschmann spirals:
• Whorled Mucus Plugs.

Lung Finding:

• Shows airway remodeling.

Micropathological Changes:

 

• Patchy Epithelial Necrosis

• Sub-Mucosal Glandular Hyperplasia

• Hypertrophy of bronchial smooth muscle

• Reid's Index is normal.

GINA (GLOBAL INITIATIVE FOR ASTHMA) GUIDELINES

Therapy Type	Drug of Choice (DOC)
Acute Attack (Rescue Therapy)	Inhalational formoterol + Low dose inhaled corticosteroids
Maintenance Therapy	Formoterol + Low dose ICS

Brittle Asthma

• Frequent, sudden, and life-threatening attacks

• Occurs despite appropriate therapy

Types of Brittle Asthma

• Airway Hyperresponsiveness assessed by: 
• MCT (Methacholine Challenge Test).

• IgE levels: 
• RAST (Radio AllergoSorbent Test).

• Non Invasive Test to assess airway inflammation: 
• Fractional Exhalation of Nitric Oxide (FeNO).

Pulmonary Function Tests:

• ↓ FEV1/FVC ratio.

Peak expiratory flow meters

• Portable, hand-held devices

• Used at home for monitoring PEFR

• Increase diurnal variability of PEFR (peak expiratory flow rate) >13%

Treatment of asthma in children

• As per the latest GINA (Global Initiative for asthma),
• All children with Bronchial Asthma
• daily dose ICS + SABA
• either Symptom driven or daily.
• No role of SABA only Rx in managing acute exacerbations
• It increases r/o exacerbations

Metered dose inhaler

• Used in drug delivery in children with bronchial asthma

• Parts
• Blue colored structure:
• Metered dose inhaler,
• Contains bronchodilator
• White-colored structure:
• Spacer,
• Must since it improves in drug delivery
• Baby mask:
• Required in < 4 years age children.

Management of status asthmaticus in a child

• Medical emergency

• Also known as acute severe asthma

• The pulmonary index score is used for the assessment of the severity

• Primary management
• airway, breathing and circulation
• (Chest x-ray and ABG to look for ventilation therapy)

• Start oxygen therapy and admission

• Continuous nebulization
• levosalbutamol/MDI

• Start systemic steroids
• Inj. hydrocortisone → f/b oral prednisolone
• Ipratropium nebulization can be used

• In case of no improvement:
• Inj. Magnesium sulfate,
• theophylline
• ketamine

Q. A 2-year-old girl is brought with a sudden onset cough and difficulty in breathing. There is no history of fever. On probing, there was a history of choking while feeding. The x-ray is shown below. What is the diagnosis?

• Ans. Foreign body aspiration

• More radiolucent

• Hyperinflated right lung → Air trapping → Expiratory CXR

• M/c obstructs Right bronchus

• Method of choice for foreign body removal:
• Rigid bronchoscopy
• Flexible bronchoscope is used nowadays

Asphyxial Triad (Mnemonic: CPC)

• Cyanosis

• Congestion of viscera

• Tardeus spots → Petechial hemorrhage

Most vulnerable brain regions to Hypoxia

1. Cortical boundary zones (grey matter)

2. Hippocampus
• CA1 sector (Sommer’s area)
• Subiculum

3. Cerebellar folia

4. Globus pallidus (basal ganglia)

Pathology

• Blockage of the nasal passages
• due to persistence of buccopharyngeal membrane

• Choana:
• Outlet of the nose.
• Communicates nasal cavity with nasopharynx.
• Choanal atresia is no communication.

• Two types:
• Bony.
• Membranous.

• Can be unilateral or bilateral.

• Associated with CHARGE syndrome:
• C - Coloboma Iridis.
• H - Heart defects: ASD/VSD.
• A - Atresia.
• R - Retardation: Growth/mental.
• G - Genital malformations: Hypospadias.
• E - Ear abnormalities.

• Cyclical cyanosis:
• Cyanosis at rest.
• Disappears on crying.
• Seen only in bilateral (b/l) choanal atresia.
• Child is an obligate nose breather until 3 months.
• Crying creates negative intrathoracic pressure, pulling air in.
• B/l choanal atresia is an emergency.

Symptoms

• Difficulty in breathing and feeding

• Cyanosis

• Irritability

Initial management:

• Facilitate oral breathing by:
• Keeping the mouth open
• Pulling the tongue forward manually using oral digital manipulation

Further management:

• Placement of:
• Plastic oropharyngeal airway or
• McGovern open-tip nipple

Treatment for b/l choanal atresia:

• Introduce McGovern nipple (oral airway and feeding nipple).

• Follow with tracheostomy.

• Correction of atresia at 1.5 - 2 years.
• Cannot correct at birth due to:
• Small nasal cavity.
• Low child weight.

Unilateral (U/l) choanal atresia:

• Not an emergency.

• Can be operated at any time.

• Child breathes through patent nostril.

• Not present at birth.

• Presents with constant nasal discharge or unilateral rhinorrhea.
• Absence of air bubble in nasal discharge.

• Diagnosis:
• Resistance felt on inserting infant feeding tube.
• X-ray after radio opaque dye.
• CT showing Choanal atresia.