Acute laryngotracheobronchitis, commonly known as croup, is a respiratory condition that primarily affects infants and young children. It is characterized by inflammation of the larynx (voice box), trachea (windpipe), and bronchi (large airways in the lungs). Croup is often caused by viral infections, with parainfluenza virus being a common culprit

1. Acute Laryngotracheobronchitis

2. DEFINITION:
•Acute Laryngotracheobronchitis as the name implies, refer to inflammation
of larynx trachea and bronchi
• Laryngotracheobronchitis ( ALTB)( Bacterial tracheitis or
Laryngotracheobronchitis).
•May progress rapidly and become a serious problem within a matter of
hours.
•Very common cause of a Cough, stridor, and hoarseness in children with a
fever.

4. PATHOPHYSIOLOGY:
• viruses causing acute infectious crop are spread through either direct
inhalation from a cough and/or sneeze or by contamination of hands from
contact with fomites with subsequent touching the mucosa of the eyes, nose
and or mouth.
•First infects the nasal Pharyngeal mucosal epithelia, then spreads to the
subglottic space.
•Inflammation and oedema of the subglottic larynx and trachea, especially
near the cricoid cartilage, are most clinically significant.
• This narrowing results in the seal like barky cough , turbulent airflow,
stridor , and chest wall retractions.
•. Decreased mobility of the vocal cords due to oedema leads to the
associated hoarseness.

6. EPIDEMIOLOGY:
• The most common paediatric illness that causes acute stridor,
•its primarily a disease of infants and toddlers, with an age peak incidence of age
6 months to 36 months (3 years) .
•Although uncommon after age 6 , crop may be diagnosed in the preteen and
adolescent years, and rarely in adults.
• The disease occurs most often early winter , But may present at any time of the
year.
• Approximately 5% of children will experience more than 1 episode.
• it generally occurs after an upper respiratory infection with fairly mild rihinitis
and pharyngitis.

7. AETIOLOGY:
• This condition is usually of viral origins:
*Parainfluenza Viruses: parainfluenza Viruses ( types 1,2,3) are responsible
for about 80% of crop cases With parainfluenza types 1 and 2 accounting for
nearly 66% of cases.
* Other viruses that are known to cause ALTB include respiratory Syncytial
virus ( RSV), rhinovirus, enterovirus, influenza,and adenovirus.
* Bacterial invasion , usually Staphylococcal , follows the original infection.
*Mycoplasma pneumoniae , has also been identified in a few cases of ALTB .

8. CLINICAL MANIFESTATIONS:
• Within 1-2 days, the characteristics sign of hoarseness,
• Barking cough
•Inspiratory stridor develop
• Along with a variable degree of respiratory distress
• Symptoms are perceived as worsening at night
• Fever that may reach 40°C to 40.6°C
• As the disease progress, marked laryngeal oedema occur
• The child breathing become difficult
• The pulse is rapid , and cyanosis may appear
• Heart failure and acute respiratory embarrassment can result
• Respiratory embarrassment the sign of being embarrassed namely rapid
and shallow breathing, blushing, or blanching of the skin of the face and ears
diaphoresis and palpitations. Not to be confused with feeling ashamed

9. ASSESSMENT AND DIAGNOSTIC FINDINGS:
• Primarily a clinical diagnosis, with the diagnostic clues based on
presenting history and physical examination findings.
• Pulse oximetry : oximetry readings are within the normal reference
range for most patients.
• However, this monitoring is helpful to assess for the need for
supplemental oxygen support and to monitor for worsening respiratory
compromise as evidence with tachypnea and poor of maintenance of
oxygen saturations.
Several scoring system can evaluate the severity of respiratory distress.
The Westley score assess the following ;
√ Cyanosis
√ Level of consciousness

11. √ Retractions
• Can also have wheezing
• crackles
• decreased air movement
• Tachypnea
• Chest wall , subcostal retractions , nasal flaring, sitting
in a sniffing position , suprasternal retractions, grunting
accessory muscles use.
• Vitals, mental status, hydration status, and air
movement help determine the treatment and disposition.
• Radiographs are not necessary to diagnose croup but can
be obtained if the diagnosis is .
• are not required in uncomplicated cases
• The “steeple sign” due to subglottic narrowing can be
seen on plain films of the chest in Patients.

12. TREATMENT:
• The major goal of treatment for ALTB is to maintain an airway and
adequate air exchange.
• Antimicrobial therapy is ordered
• Child is placed in a supersaturated atmosphere, such as a
croupette or some other kind of mist tent that also can include
administration of oxygen.
• To achieved bronchodilation nebulized epinephrine may be
administered.
• Nebulization is usually administered every 3 or 4 hours.

15. • The child required the careful observation for the
reappearance of symptoms.
• It necessary intubation with a nasotracheal tube may be
performed for a child with severe distress unrelieved by
other measures.
• Antibiotics administered parenterally initially and
continued after the temperature has normalized.