CROUP SYNDROMES

• Acute inflammatory disease of

the larynx.

• Early winter.

• Mostly viral cause.

• Symptoms persist 4-7 days.

• VIRAL CROUP • Viral croup generally affects young children 6 months to 5 years of age in the fall and early

winter and is most often caused by Parainfluenza virus serotypes.

• However, many other viral organisms as well as M.pneumoniae can cause croup.

• Edema in the subglottic space accounts for the predominant signs of upper airway

obstruction although inflammation of the entire airway is often present.

SYMPTOMS AND SIGNS

• Usually, a prodrome of upper respiratory tract symptoms is followed by a

barking cough and stridor.

• Fever is usually absent; patients with mild disease may have stridor when

agitated.

• As obstruction worsens, stridor occurs at rest, accompanied in severe

cases by retractions, air hunger( severe

breathlessness) and cyanosis.

CLINICAL FINDINGS • On examination, the presence of cough and the absence of drooling favor the diagnosis of viral

croup over epiglottitis.

• Imaging are not routinely indicated for patients with classic presentation of croup. For atypical

presentation, X-ray shows subglottic narrowing (the steeple sign) without the irregularities seen

in tracheitis and a normal epiglottis.

TREATMENT • Treatment of viral croup is based on the symptoms.

• Mild croup, signified by a barking cough and no stridor at rest, requires supportive therapy with oral hydration and minimal handling.

• Mist therapy has historically been used but clinical studies do not

demonstrate effectiveness.

1. Patients with stridor at rest require active intervention.

2. Oxygen should be administered to patients with oxygen desaturation.

3. Nebulized racemic epinephrine (0.05 ml/kg, maximum 1.5ml ) of 2.25%

solution diluted in sterile saline, is commonly used because it has a rapid

onset of action within 10-30 minutes, it is effective in alleviating symptoms

and decreasing the need for intubation.

• Dexamethasone, 0.6mg/kg intramuscularly as one dose, improves symptoms, reduces the duration of hospitalizations and frequency of intubations, and permits earlier discharge from the emergency department.

• Oral dexamethasone (0.15 mg/kg) may be equally effective for mild to moderate croup

• Inhaled budesonide (2-4 mg) also improves symptoms and decreases hospital stay and may be

as effective as dexamethasone.

• Dexamethasone has also been shown to be more effective than prednisolone in equivalent

doses.

• The use of heliox, a mixture of helium and oxygen, improves turbulent

airflow, but is not superior to nebulized medication. Its use is limited in

hypoxic children because of its low fractional concentration of inspired

oxygen.

• If symptoms resolve within 3-4 hours of glucocorticoids and nebulized

epinephrine, patients can safely be discharged without fear of a sudden

rebound in symptoms.

• If, however, recurrent nebulized epinephrine treatments are required or if

respiratory distress persists, patients require hospitalization for close

observation, supportive care, and nebulization treatment as needed.

• In patients with impending respiratory failure, an airway must be

established. Intubation with an endotracheal tube of slightly smaller

diameter than would ordinarily be used is reasonably safe. Extubation should

be accomplished within 2-3 days to minimize the risk of laryngeal injury.

Other underlying causes should be considered in hospitalized patients with persistent

symptoms over 3-4 days despite treatment.

PROGNOSIS • Most children with viral croup have an uneventful course and improve within a few days.

• Some evidence suggests that patients with a history of croup associated with wheezing may

have airway hyper activity. It is not always clear if the hyper reactivity was present prior to the

croup episode or if the viral infection causing croup altered airway function.

BACTERIAL TRACHEITIS

• Bacterial tracheitis (pseudomembranous croup) is a severe life-threatening form of

laryngotracheobronchitis.

• Tracheitis is a common cause of pediatric airway emergency requiring admission to the pediatric

intensive care unit. This diagnosis must be high in the differential when a patients present with

sever upper airway obstruction and fever.

• The organism most often isolated is Staphylococcus aureus, but organisms such as H influenza ,

group A Streptococcus pyogenes, Neisseria species, Moraxella catarrhalis, and other have been

reported.

• A viral prodrome is common.

• The disease probably represents localized mucosal invasion of bacterial in patients with primary

viral croup, resulting in inflammatory edema, purulent secretions, and pseudo membranes.

• Although cultures of the tracheal secretions are frequently positive, blood

cultures are almost always negative.

SYMPTOMS AND SIGNS • The early clinical picture is similar to that of viral croup. However, instead of gradual

improvement, patients develop higher fever, toxicity, and progressive or intermittent severe

upper airway obstruction that is unresponsive to standard croup therapy.

• The incidence of sudden respiratory arrest or progressive respiratory failure is high, requiring

airway intervention. Finding of toxic shock and the acute respiratory distress syndrome may be

also being seen. Aggressive medical treatment and debridement is indicated.

LAB FINDINGS AND IMAGING • The white cell count is usually elevated with a left shift. Cultures of tracheal secretions usually

demonstrate one of the causative organisms.

• Bronchoscopy showing a normal epiglottis and the presence of copious purulent tracheal

secretions and membranes confirms the diagnosis.

TREATMENT • Patients with suspected bacterial tracheitis will require direct visualization of the airway in a

controlled environment and debridement of the airway. Most patients will be intubated

because the incidence of respiratory arrest or progressive respiratory failure is high.

• Patients may also require debridement, humidification, frequent suctioning, and intensive care

monitoring to prevent endotracheal tube obstruction by purulent tracheal secretion.

• Intravenous antibiotics to cover S.aureus, H influenza, and the other organisms are indicated.

Epiglottitis With the introduction of the Haemophilus influenzae conjugate vaccine, the incidence of epiglottitis

is rare in countries with immunization programs. If disease occurs, it is likely to be associated with H

influenzae in unimmunized children, or another organism such as nontypeable H influenzae,

Neisseria meningitides, or Streptococcus species in immunized populations.

Signs and symptoms

The classic presentation is a sudden onset of high fever, dysphagia, drooling, muffled voice, inspiratory retractions, cyanosis, and soft stridor. Patients often sit in the so-called sniffing dog position, with the neck hyperextended and the chin stretched forward, which gives them the best airway possible under the circumstances. Progression to total airway obstruction may occur and result in respiratory arrest.

The definitive diagnosis is made by direct inspection of the epiglottis, a procedure that should be done by an experienced airway specialist under controlled conditions (typically in the operating room during intubation). The typical findings are a cherry-red and swollen epiglottis and swollen arytenoids.

Imaging - Lateral neck radiographs may be helpful in demonstrating a classic “thumbprint” sign caused

by the swollen epiglottis. Obtaining radiographs, however, may delay important airway intervention.

Treatment Once the diagnosis of epiglottitis is made, endotracheal intubation must be performed immediately in children but not necessarily in adults. After an airway is established, cultures of the blood and epiglottis should be obtained and the patient should be started on appropriate intravenous antibiotics to cover H influenzae and Streptococcus species. Extubation can usually be accomplished in 24–48 hours, when direct inspection shows a significant reduction in the size of the epiglottis. Intravenous antibiotics should be continued for 2–3 days, followed by oral antibiotics to complete a 10-day course.

References:

1- Hay, W., 2009. Current Pediatric Diagnosis & Treatment. 24th ed. New York: McGraw-Hill

Medical.

2- Marcdante, K. and Kliegman, R., n.d. Nelson Essentials Of Pediatrics. 8th ed. Philadelphia: W.B.

Saunders Co.