Bacterial Tracheitis

Bacterial tracheitis is a diffuse inflammatory process of the larynx, trachea, and bronchi with adherent or semiadherent mucopurulent membranes within the trachea. The major site of disease is at the cricoid cartilage level, the narrowest part of the trachea. Acute airway obstruction may develop secondary to subglottic edema and sloughing of epithelial lining or accumulation of mucopurulent membrane within the trachea. Signs and symptoms are usually intermediate between those of epiglottitis and croup.[4, 5]

Bacterial tracheitis may be more common in the pediatric patient because of the size and shape of the subglottic airway. The subglottis is the narrowest portion of the pediatric airway, assuming a funnel-shaped internal dimension. In this smaller airway, relatively little edema can significantly reduce the diameter of the pediatric airway, increasing resistance to airflow and work of breathing. With appropriate airway support and antibiotics, most patients improve within 5 days.

Although the pathogenesis of bacterial tracheitis is unclear, mucosal damage or impairment of local immune mechanisms due to a preceding viral infection, an injury to the trachea from recent intubation, or trauma may predispose the airway to invasive infection with common pyogenic organisms.

Frequency

United States

Tan and Manoukian reported that 500 children were hospitalized for croup at one pediatric hospital over a 32-month period.[6] Approximately 98% had viral croup, and 2% had bacterial tracheitis. Cases usually occur in the fall or winter months, mimicking the epidemiology of viral croup.

A study that described the frequency and severity of complications in hospitalized children younger than 18 years with seasonal influenza (during 2003-2009) and 2009 pandemic influenza A(H1N1) (during 2009-2010) reported that out of 7293 children hospitalized with influenza, less than 2% had complications from tracheitis. However, along with other rare complications, tracheitis was associated with a median hospitalization duration of more than 6 days, with 48%-70% of children requiring intensive care.[7]

International

According to a recent study, bacterial tracheitis remains a rare condition, with an estimated incidence of approximately 0.1 cases per 100,000 children per year.[8]

Mortality/Morbidity

The predominant morbidity and mortality is related to the potential for acute upper airway obstruction and induced hypoxic insults. The mortality rate has been estimated at 4-20%. In the acute phase, patients generally do well if the airway is adequately managed and if antibiotic therapy is promptly initiated.

Sex

In most epidemiologic studies, male cases are preponderant. Gallagher et al reported a male-to-female predominance of 2:1.[9]

Age

Bacterial tracheitis may occur in any pediatric age group. Gallagher et al reported 161 cases of patients younger than 16 years.[9] The age range was from 3 weeks to 16 years, with a mean age of 4 years. This is in contrast to viral laryngotracheobronchitis, which occurs in patients aged 6 months to 3 years.

Symptoms of bacterial tracheitis may be intermediately between those of epiglottitis and croup. Presentation is either acute or subacute.

• In the classic presentation patients present acutely with fevers, toxic appearance, stridor, tachypnea, respiratory distress, and high WBC counts. Cough is frequent and not painful.

• In a study by Salamone et al, a significant subset of older children (mean age, 8 y) did not have severe clinical symptoms.[10]

• The prodrome is usually an upper respiratory infection, followed by progression to higher fever, cough, inspiratory stridor, and a variable degree of respiratory distress.[23]

• Patients may acutely decompensate with worsening respiratory distress due to airway obstruction from a purulent membrane that has loosened.

• Patients have been reported to present with symptoms and signs of bacterial tracheitis and multiorgan failure due to exotoxin-producing strains of Staphylococcus aureus or Streptococcus pyogenes in the trachea.

• A high index of suspicion for bacterial tracheitis is needed in children with viral croup–like symptoms who do not respond to standard croup treatment or clinically worsen.

The following physical findings may be noted:

• Inspiratory stridor (with or without expiratory stridor)

• Fever

• Barklike or brassy cough

• Hoarseness

• Worsening or abruptly occurring stridor

• Varying degrees of respiratory distress

  • Retractions

  • Dyspnea

  • Nasal flaring

  • Cyanosis

• Sore throat, odynophagia

• Dysphonia

• No drooling

• No specific position of comfort (The patient may lie supine.)

The following causes have been noted:

• S aureus: Community-associated methicillin-resistant S aureus (CA-MRSA) has recently emerged as an important agent in the United States; this could result in a greater frequency of MRSA strains that cause tracheitis.

• S pyogenes, Streptococcus pneumoniae, and other alpha hemolytic streptococcal species

• Moraxella catarrhalis: Recent reports suggest it is a leading cause of bacterial tracheitis and associated with increased intubation.

• Haemophilus influenzae type B (Hib): This cause is less common since the introduction of the Hib vaccine.

• Klebsiella species

• Pseudomonas species

• Anaerobes

• Peptostreptococcus species

• Bacteroides species

• Prevotella species

• Other

  • Mycoplasma pneumoniae

  • Mycobacterium tuberculosis (endobronchial disease)

  • H1N1 influenza[11]

Obtain bacterial culture and Gram stain of tracheal secretions and blood cultures in patients with suspected bacterial tracheitis.

Radiography of the neck may be indicated.

• Neither definitive nor essential

• Portable, not in the radiology suite, only in the stable patient

• May reveal subglottic narrowing on anteroposterior (AP) views - Steeple sign, similar to croup (See the image below.)

  Steeple sign.

• May reveal clouding of tracheal air column or irregular tracheal margin on lateral view

• Concretions of epithelium and inflammatory cells possibly mimicking a foreign body

Laryngotracheobronchoscopy is indicated.

• Only definitive means of diagnosis

• Direct visualization and culture of purulent tracheal secretions

• May be therapeutic by performing tracheal toilet and stripping purulent membranes

• Pediatric-sized bronchoscopes and experts at pediatric airway management not available at all facilities

Treatment of bacterial tracheitis consists of the following:

• Airway

  • Maintenance of an adequate airway is of primary importance.[12]

  • Avoid agitating the child. If the patient's respiratory status deteriorates, it is usually because of movement of the membrane, and bag-valve-mask ventilation should be effective.

  • If intubation is required, use an endotracheal tube 0.5-1 size smaller than expected in order to minimize trauma in the inflamed subglottic area. Frequent suctioning and high air humidity is necessary to maintain endotracheal tube patency; therefore, use the most appropriate-sized tube (without causing trauma). Most patients (57-100%) require eventual intubation.

• Intravenous access and medication

  • Once the airway is stabilized, obtain intravenous access for initiation of antibiotics.

  • Antibiotic regimens have traditionally included a third-generation cephalosporin (eg, cefotaxime, ceftriaxone) and a penicillinase-resistant penicillin (eg, oxacillin, nafcillin). Recently, clindamycin (40 mg/kg/d intravenously [IV], divided every 8 h) is used instead of penicillinase-resistant penicillin against community acquired–methicillin-resistant S aureus (CA-MRSA) in places where resistance rates of CA-MRSA to clindamycin is low.[13]

  • Vancomycin (45 mg/kg/d IV, divided every 8 h), with or without clindamycin, should be started in patients who appear toxic or have multiorgan involvement or if MRSA is prevalent in the community.

Tracheostomy is rarely necessary unless injury or trauma to the airway has caused scarring and documented narrowing of the airway. Tracheostomy is necessary if the patient has failed extubations despite appropriate medical management or if intubation is prolonged. Pulmonary toilet is potentially better with tracheostomy.

The following consultations may be indicated:

• Otorhinolaryngologist - For endoscopic procedures and acute airway management

• Pediatric intensivist - Necessary because of potential for acute decompensation

Class Summary

Empiric antimicrobial therapy in bacterial tracheitis must be comprehensive and should cover all likely pathogens in the context of the clinical setting.

Oxacillin (Bactocill, Prostaphlin)

Provides empiric therapy against etiologic agents, specifically penicillinase-producing strains of Staphylococcus.

Cefotaxime (Claforan)

Provides empiric therapy, especially against H influenzae, and modest activity against anaerobes.

Vancomycin (Vancocin)

May be used in severe cases or in cases with a history of allergies instead of oxacillin for coverage of gram-positive organisms (eg, S aureus, S pyogenes).

Clindamycin (Cleocin)

Use in combination with chloramphenicol in patients who are allergic to penicillin. Clindamycin in combination with cefuroxime is an acceptable regimen for patients who are not allergic.

Patient should complete an appropriate course (usually 10 d) of oral antibiotics.

Consider extubation when bacterial tracheitis appears to be resolving, especially with decreased secretions suctioned from the endotracheal tube.

Transfer is required for patients in respiratory distress, patients in need of a pediatric intensive care unit, and patients who need a pediatric-sized bronchoscope.

The following complications have been reported:

• Pneumonia - Reported in 19-60% of cases (Guidelines for avoiding health care–associated pneumonia have been established.[14] )

• Septicemia

• Toxic shock

• Adult respiratory distress syndrome (ARDS)

• Endotracheal tube complications

  • Plugging, accidental extubation

  • Postextubation stridor, subglottic stenosis

• Anoxic encephalopathy

• Cardiorespiratory arrest

A retrospective study by Gross et al, in which four patients who received antibiotic treatment for bacterial laryngotracheitis showed improvement in presumed iatrogenic laryngotracheal stenosis, suggested that airway bacterial growth is significantly involved in adult postintubation airway injury. The patients had a history of intubation and/or tracheostomy, with complete resolution of upper airway obstruction seen in three of the patients after laryngotracheitis treatment and significant improvement of airway status seen in the fourth.[15]

Once the patient is past the acute phase, complete recovery is expected.

Keep immunizations up-to-date.