Acute Laryngotracheobronchitis (Croup)

Parainfluenza virus types 1, 2, and 3

Parainfluenza virus type 1

Glottis and subglottic tissues

Acute laryngotracheobronchitis (croup)

3 months to 5 years

Males

Cold season

15%

Adenovirus, rhinovirus, RSV, measles, human metapneumovirus, and coronavirus

Barking cough

Inspiratory stridor

At night

Mild febrile respiratory infection

Hoarseness

Decreased breath sounds, rhonchi, rales, and occasional crackles

Deep red laryngeal mucosa and subglottic swelling

Steeple sign

Tapering of the airway due to subglottic edema

No

Viral culture, CBC, laryngoscopy, and lateral neck X-ray

0–2

3–5

6–11

12–17

Airway management, epinephrine, and corticosteroids

To improve air exchange and reduce tracheal collapse

No

Rapid but temporary relief of airway obstruction

Racemic epinephrine or nebulized L-epinephrine

1:1,000 (1 mg/mL) epinephrine diluted with 5 mL normal saline

Alpha-adrenergic stimulation causes precapillary arteriolar constriction and reduces mucosal edema

IV dexamethasone or nebulized budesonide

Their anti-inflammatory effect

Epinephrine and corticosteroids

Acute laryngotracheobronchitis (croup)

Mostly children younger than 3 years

No

Viral upper respiratory tract infection

Pseudomembranous or membranous tracheitis

Haemophilus influenzae type b (Hib) vaccine

Staphylococcus aureus

Staphylococcus aureus

Haemophilus influenzae, Moraxella, and anaerobes

Brassy cough

Toxic-looking with respiratory distress

High-grade fever of 39–40°C

No

Secure the airway before obtaining history

Airway management and antimicrobials

No

Epiglottitis and other upper airway infections

Age range, anatomical site, clinical history, and toxic appearance

Wet cough for over 4 weeks, no alternative cause, and resolution after appropriate antibiotics

More than 4 weeks

Signs and symptoms suggesting another cause, such as TB or asthma

2–4 weeks

10 months to 5 years

No

Relatively well with normal growth and development

Normal

Normal

Normal

More than 2–4 weeks

Asthma

Wheezing

25–58%

13–58%

17–59%

23%

They reduce antibiotic penetration and promote persistent infection

Haemophilus influenzae

Co-amoxiclav and second-generation cephalosporins

They can cause nausea and vomiting

2–4 weeks

Acute bronchitis → PBB → chronic bronchitis → bronchiectasis

Less than 3 weeks

When cough persists for 3–4 weeks

When cough persists for more than 4 weeks

Bronchiectasis

Recurrent colds, wheezing, cough, phlegm production, and impaired ventilatory function

11 years

To provide appropriate treatment and prevent long-term consequences

Viral upper respiratory tract infection

No

Younger children and males

Winter or the cold and rainy season

Viral infection

Respiratory syncytial virus (RSV)

Influenza A and B, parainfluenza 1 and 2, paramyxovirus, adenovirus, rubeola, and rhinovirus

Approximately 3 days

Hoarseness

Dry cough

Dry cough becomes productive and may last 2 weeks

Fever

Chest pain

Vomiting

Coarse or harsh breath sounds without rales

Crackles

Normal or increased bronchial markings

Supportive care

Yes

Only when bacterial infection is suspected or confirmed

In immunocompromised patients

Asthma

Respiratory syncytial virus (RSV)

More than 50%

Parainfluenza, adenovirus, and Mycoplasma

Children in the first 2 years of life

1–3 months

Males

Winter and early spring

Not being breastfed, cigarette smoke exposure, and crowded environments

Asthma

URTI symptoms, fever, and respiratory distress

Tachypnea, hyperexpanded chest, and rales

Pulmonary hyperinflation

It increases

Hyperinflation without infiltrates

Approximately 30%

Supportive care

No

Limited evidence of benefit and difficulty of administration

When wheezing is present

When bacterial infection is suspected or confirmed

RSV prevention in immunocompromised patients

An RSV vaccine

32–36 weeks of gestation

Severe RSV disease during early infancy

A long-acting monoclonal antibody for RSV prevention

Immunocompromised newborns and infants younger than 8 months entering their first RSV season

Selected older infants with risk factors

79%

Smoking in the household

Bronchial asthma

Uncomplicated and complicated

Epiglottitis, croup, tracheobronchitis, bronchiolitis, and pneumonia

Atelectasis, bacterial tracheitis, empyema, lung abscess, mediastinitis, and pneumothorax

150.7 million cases

95%

13%

15 million deaths

97%

4–5 million deaths, or 25–33% of deaths

Approximately 3 million

Fourth leading cause of death

First

829 per 100,000

Children younger than 1 year

235.5 per 100,000

Impaired ciliary mechanisms and immature body defenses

50 per 100,000

43 per 100,000

Community-acquired, hospital-acquired, aspiration, anaerobic, immunocompromised-host, geographically restricted, and recurrent pneumonia

Community-acquired pneumonia

Hospital-acquired pneumonia

Low culture yield and frequent indeterminate etiology

Approximately 50%

Approximately 10%

Humans

Rainy season, winter, and spring

Males

No

Droplet transmission

Difficult to determine

Up to 24 hours after treatment begins

Avoid interaction with others until effective antimicrobial therapy has started

Tuberculosis, pertussis, diphtheria, and measles

Group B Streptococcus and enteric Gram-negative rods

Younger than 30 days

Up to 2 months

Systemic sequelae of congenital infection

High

Nonspecific diffuse interstitial process

CMV, HSV, roseola, and rubella

Adenovirus, enterovirus, and RSV

Group B Streptococcus and enteric Gram-negative rods

Early in postnatal life

Respiratory symptoms and sequelae of septicemia

Systemic ground-glass infiltrates and air bronchograms

Penicillin G plus gentamicin or amoxicillin plus gentamicin

2 months to 3 years

28 days to 1 year

Highly contagious with a brief incubation period

No

4–6 weeks

Haemophilus influenzae and Streptococcus pneumoniae

Delayed development, bacteremia, and CNS complications

30%

20%

10%

10%

Older than 5 years

Marked decrease in overall incidence

Age, underlying disease, and environmental factors

Enterobacter and Staphylococcus aureus

Toxic-looking appearance

Abscesses and skin lesions

Group B Streptococcus and enteric Gram-negative rods

Systemic ground-glass infiltrates and air bronchograms

Penicillin G plus gentamicin or amoxicillin plus gentamicin

Walking pneumonia

Patients appear relatively well despite infection

7 years

Preschool and school-age children

No

Chlamydia pneumoniae, Mycoplasma pneumoniae, and respiratory viruses

2001

11.6 months

59%

18%

14%

8%

Severe acute respiratory syndrome (SARS)

Fever, headache, malaise, gastrointestinal complaints, restlessness, and apprehension

Tachypnea, cough, dyspnea, sputum production, shallow breathing, nasal flaring, and grunting

When complicated by pulmonary effusion

Tachypnea

Chest indrawing or retractions

It indicates possible hypoxemia

Decreased breath sounds, rales, dullness, and decreased tactile and vocal fremitus

Intercostal retractions

Restricted chest wall motion, diaphragmatic irritation, and empyema

Skin abscess, soft tissue abscess, sinusitis, otitis media, meningitis, and epiglottitis

Confluent bronchopneumonia, cavitation, pneumatoceles, empyema, and fistula

Focal lobar involvement

Diffuse interstitial pneumonia with increased pleural involvement

Infection along the bronchial tree, similar to viral pneumonia

Brassy or dry cough

Respiratory rate greater than 50/min

Respiratory rate greater than 40/min

Respiratory rate greater than 30/min

Tachypnea, chest indrawing, and fever

Tachypnea, crackles, and fever

Fever, tachypnea, tachycardia, and at least one abnormal chest finding

Diminished breath sounds, rhonchi, crackles, or wheezes

Yes, especially in younger children

Those at moderate to high risk of pneumonia-related mortality

PCAP C or PCAP D

Chest indrawing

Unreliable caregiver or living far from a health facility

To assess morbidity and mortality risk, not pneumonia severity

3 months to 18 years

At least one criterion

Lethargy

No

Chest X-ray

70%

Interpretation depends on the reader

Chest X-ray, CBC, and culture and sensitivity

Sputum examination, blood gas, pulse oximetry, ESR, and CRP

Complicated cases involving lung abscess, empyema, or pleural effusion

No

Chest X-ray

Chest X-ray

Anteroposterior (AP) view

Posteroanterior (PA) and lateral views

Suspected complications or recurrent pneumonia

Portable, inexpensive, radiation-free, and less affected by movement

Yes

Operator dependency

It cannot visualize the entire lung or deep parenchymal areas simultaneously

Subcapsular or subclavicular consolidations that do not reach the pleura

The spleen or air in the stomach

Pulmonary consolidation, positive air bronchogram, abnormal pleural line, and pleural effusion

Lung consolidation and bronchogram

A precursor of the hormone calcitonin

Bacterial endotoxins and inflammatory cytokines

Bacterial from viral etiology

No

To identify causative bacteria

At least 25 leukocytes and fewer than 10 squamous epithelial cells

It is inexpensive, noninvasive, and readily available

Host factors and external factors

Age younger than 6 months

Inability to feed

Respiratory failure and increased respiratory rate

Dehydration

Pulmonary complications, comorbidities, immunocompromised state, and extrapulmonary involvement

Unreliable caregiver compliance and inability to follow up

Amoxicillin

No

40–50 mg/kg/day every 8 hours

80–90 mg/kg/day every 12 hours for 5–7 days

80–90 mg/kg/day every 12 hours for 5–7 days

20–30 mg/kg/day every 12 hours for 7 days

Diarrhea, abdominal pain, nausea, vomiting, and rash

Diarrhea, abdominal pain, nausea, vomiting, headache, and dizziness

Diarrhea, nausea, vomiting, headache, and chills

No

No

When penicillin-resistant pneumococci or beta-lactamase-producing H. influenzae are prevalent

Age-dependent tachypnea and evidence of respiratory failure

\$PaO_2/FIO_2<250\$ mmHg

Need for mechanical ventilation

Shock

Bilateral or multilobe opacification

Need for vasopressors

Less than 1 mL/kg/hour or less than 20 mL/hour

Hib immunization status

200,000 units/kg/day every 6 hours