EM@3AM: Bacterial Tracheitis

Authors: Jacob Tauferner, MD (EM Resident Physician, UTSW/ Dallas, TX) and Mihir Patel, MD (EM Attending Physician, Dallas, TX) // Reviewed by: Sophia Görgens, MD (EM Physician, BIDMC, MA); Cassandra Mackey, MD (Assistant Professor of Emergency Medicine, UMass Chan Medical School); Alex Koyfman, MD (@EMHighAK); Brit Long, MD (@long_brit)

Welcome to EM@3AM, an emDOCs series designed to foster your working knowledge by providing an expedited review of clinical basics. We’ll keep it short, while you keep that EM brain sharp.

Answer: Bacterial tracheitis

Introduction

• Bacterial tracheitis (BT), also known as bacterial croup or laryngotracheobronchitis, is a potentially lethal infection of the subglottic trachea. [2]
  • Bacterial infection usually preceded by viral infection.
  • Typically in children less than 6 years of age. [3]
  • Can be rarely seen spontaneously in adults.
  • Tracheostomy dependent patients of any age are also at risk. [2]
• There is a mainstay concern for airway protection in the setting for BT due to thick mucopurulent secretions causing narrowing and obstruction of the airway. [2-4]

Etiology

• The most common preceding viruses include:
  • Influenza A and B
  • Respiratory syncytial virus (RSV)
  • Parainfluenza virus
  • Measles virus
  • Enterovirus [2][3]
• In BT bacteria invade the trachea and stimulate local and systemic inflammatory responses leading to production of thick, mucopurulent exudates, ulceration and sloughing of the tracheal mucosa and upper airway obstruction. [2][3][5]
• Implicated bacteria most commonly include:
  • Staphylococcus aureus (including MRSA)
  • Streptococcus pneumoniae,
  • Streptococcus pyogenes,
  • Moraxella catarrhalis,
  • Haemophilus influenzae type B (HiB),
  • Haemophilus influenzae (non-typeable), and less commonly,
  • Pseudomonas aeruginosa,
  • Escherichia coli,
  • Klebsiella pneumonia,
  • Anaerobic organisms [2-4]
• Long-term tracheostomy patients are presumed to be colonized by a single or multi-bacterial species predisposing them to BT caused most commonly by S. aureus, Gram-negative bacilli, Pseudomonas aeruginosa, and Streptococcus pneumoniae.
• Meticulous tracheostomy care is imperative in minimizing risk of BT in this population. [2][6][7]

Epidemiology

• Annual incidence of bacterial tracheitis has an estimated incidence of 0.1 to 1 case per 100,000 children.
  • A peak incidence is seen in ages 3 to 8. [2][3]
  • The incidence rises in the fall and winter months, coinciding with seasonal viral epidemics (influenza, parainfluenza, and RSV). [2-4]

Presentation

• BT most commonly presents as prodromal symptoms that suggest a viral respiratory tract infection (rhinorrhea, post-nasal drip, cough, fever, myalgia, and sore throat) presenting a week before the acute worsening of the patient.
  • Patients then develop acute airway deterioration, high fevers, hoarseness, toxic appearance, and increased mucopurulent cough.
• Signs and symptoms include stridor (inspiratory or expiratory), fever, productive and painful cough, thick secretions, and tenderness of the trachea. [2-4]
• Tracheostomy-dependent patient symptoms of BT include high fevers, productive cough, thick mucopurulent secretions, hemoptysis, peristomal skin breakdown or cellulitis, high ventilatory peak pressures, and/or tracheostomy obstruction. [2][3]

Evaluation

• Labwork
  • CBC: A white blood cell count is variable and nonspecific. Leukocytosis, as well as mild leukopenia, are common.
  • ESR, CRP: Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are also nonspecific but are estimated to be elevated in 68% of patients.
  • Blood cultures: Blood cultures are rarely positive; however, should be obtained if suspicion for sepsis is present or if the patient is immunocompromised. [2][3]
• Imaging
  • X-ray images of the lateral or anteroposterior neck can show subglottic or tracheal narrowing (steeple sign), typically seen with croup. The epiglottis will appear normal. [2][3]
  • Chest x-rays are poorly diagnostic but can show concurrent pneumonia in approximately 50% of cases.
  • CT scans are typically not recommended in pediatric patients, but can be useful in adults with concern for tracheal stenosis or recurrent tracheitis, however airway stabilization takes precedence. [2][3]
• Definitive diagnosis is made by laryngoscopy or bronchoscopy showing normal or mildly erythematous epiglottis and an erythematous, edematous trachea with thick mucopurulent exudates. [3]

Differential

• Epiglottitis can also present with fever, upper airway obstruction, and toxic appearance. However, these patients often present with drooling and a preference for the tripod position, which is uncommon in bacterial tracheitis. [2][3]
• Bacterial tracheitis should be suspected over croup if nebulized racemic epinephrine or steroids do not improve the clinical course. [2][3][8]
• Peritonsillar or retropharyngeal abscesses will demonstrate fever, drooling, and muffled voice, associated with limited mobility of the neck. [2][8]
• Other etiologies including but not limited to: angioedema, foreign body aspiration, caustic ingestion, laryngeal malignancies, diphtheria, bacterial pneumonia. [2][3]

Management/Disposition

• ABCs and resuscitation if indicated
  • Assessment for need of definitive airway is imperative as rate of intubation is high (38-100%) in various studies. [2][3][9] Hypoxia, respiratory muscle retractions, fatigue, altered mental status, and decreased breath sounds are signs indicative of impending airway failure. [2]  If intubation is indicated, endotracheal tubes one or two sizes smaller than expected for the patient should be selected due to airway narrowing. [2]
• Antibiotics
  • Antibacterial management should be prompt and include broad-spectrum coverage, including MRSA. [2]
  • Suggested antibiotics include: ceftriaxone or cefotaxime + vancomycin or clindamycin.
  • Patients with true cephalosporin allergy may be treated with vancomycin or clindamycin + levofloxacin or ciprofloxacin. [2][3][9]

• Glucocorticoid were not shown to alter clinical course or patient outcomes. [2][3]
• Consultations:
  • Intensive care physicians for ICU placement
  • Otolaryngology to prevent morbidity and mortality and potential for help with intubation in the OR [2][9]
• Complications:
  • Acute respiratory distress syndrome (ARDS)
  • Airway obstruction
  • Anoxic encephalopathy
  • Disseminated intravascular coagulation (DIC)
  • Sepsis, septic shock
  • Tracheal stenosis
  • Death

Pearls

• Bacterial Tracheitis is a rare, potentially fatal disease that is not exclusive to children, and can affect immunocompromised and tracheostomy-dependent adult patients.
• BT typically presents with days of viral prodromal symptoms followed by acute decline with stridor, respiratory distress, and overall toxic appearance.
• Labs and x-ray can be nonspecific, and definitive diagnosis is made with direct visualization.
• Assessment of necessity for definitive airway takes precedence in BT in conjunction with appropriate antibiotics.

References