Introduction

Croup

Young children can get croup, also known as laryngotracheobronchitis, a respiratory infection. Viral infections most commonly cause the disease. Your child's windpipe (trachea) and voice box (larynx) expand as a result of croup. Their breathing becomes laboured and noisy due to the narrowing of the airway beneath their vocal cords caused by this swelling.

The majority of cases of croup occur in newborns and children under three. As kids get older, croup becomes less common. This is because as children get older, their windpipes get bigger and are less prone to obstruct their breathing. A characteristic cough, akin to a seal's call, is caused by croup. Although symptoms are usually moderate, they can become serious and even fatal.²

Bacterial tracheitis

An infection of the trachea is called tracheitis. It is referred to as bacterial tracheitis when bacteria are the cause. This is an uncommon disorder that mostly affects young children. It might have potentially fatal consequences if treatment is delayed.

Your windpipe is another name for your trachea. It is a crucial component of your respiratory system. Air passes through your larynx, also known as your voice box, and down your trachea when you breathe in through your mouth or nose. Your lungs get air through two tubes called bronchi that branch off from your trachea. Furthermore, when you exhale, carbon dioxide-rich air is allowed to exit your body through your trachea.⁵

What causes croup and bacterial tracheitis?

Croup

Viruses that cause acute infectious croup are transmitted by direct inhalation of air contaminated by droplets from coughing or sneezing.  It can also be transmitted  by contaminated hands after coming into contact with fomites and then touching the mucosa of the mouth, nose, or eyes.

About 80% of cases of croup are caused by parainfluenza viruses (types 1, 2, 3), with types 1 and 2 accounting for approximately 66% of cases. In premature newborns and children, the type 3 parainfluenza virus causes pneumonia and bronchiolitis. The type 4 parainfluenza virus, which includes subtypes 4A and 4B, is generally linked to less severe clinical disease and is less well understood.¹

Bacterial tracheitis

The bacteria Staphylococcus aureus is typically responsible for bacterial tracheitis. It can also be caused by other bacteria, such as:

• Streptococcus pneumoniae
• Haiemophlus influenzae
• Moraxella catarrhalis

The majority of bacterial tracheitis cases occur following a typical cold or flu. Bacteria can more readily enter your child's trachea after a URI. Infection, inflammation, and sudden swelling may result from this. Your child's trachea is short and positioned such that even slight swelling can quickly obstruct their airway.

Adults are not immune to bacterial tracheitis, however it progresses more slowly in this age group. If that happened to you, the illness might go away on its own before it obstructs your airway.⁵

What are the symptoms and signs of croup and bacterial tracheitis?

While symptoms of croup usually subside in less than a week, they can become more severe. Swollen or runny noses are common early symptoms of croup. The symptoms may intensify and the barking cough may worsen over the next 12 to 48 hours. The patients may also have stridor. Usually, symptoms worsen at night.

Additional mild signs of croup include:

• Hoarseness
• High temperature
• Skin rashes
• Redness in the eyes (conjunctivitis)
• Enlarged lymph nodes

Moderate to severe croup symptoms include:

• Trouble breathing
• Agitation or anxiety
• Retractions: the process of drawing in the skin around your child's breastbone and ribcage²

Tracheitis

Before experiencing severe symptoms of dyspnea and stridor, the majority of children have signs of a viral respiratory infection for one to three days. Acute onset, marked by high fever, respiratory stridor, and frequently profuse purulent(pus-like) discharges from the nose, occurs in a small number of youngsters. Bacterial tracheitis is an uncommon side effect of endotracheal intubation or viral croup. Children with bacterial tracheitis may experience severe illness respiratory distress, which may worsen quickly and necessitate intubation, similar to patients with epiglottitis⁴

Diagnosis

Croup

Usually, you can determine whether your child has croup by looking at their symptoms and indications. The most typical symptoms include stridor and a barking cough. Fall and winter months see an exceptionally high prevalence of this illness. The symptoms alone may be enough to make the diagnosis.

A doctor might recommend X-rays and lab tests if your child's condition is severe, although this is not common.²

Results from laboratory tests are rarely useful in confirming a diagnosis. While the white blood cell (WBC) count and differential may point to a viral cause with lymphocytosis, the complete blood cell (CBC) count is typically nonspecific. While it's usually not required, determining the precise viral cause, for example, the kind of parainfluenza virus through nasal washings can help determine whether isolation is required in a medical care setting.¹

Anteroposterior x-ray of the neck reveals a steeple sign(pencil point sign) which is a marker of the narrowing  of the airway below the vocal cords. Lateral neck x-ray also shows ballooning of the area below the pharynx when the patient breathes in.

Laryngoscopy may be needed in extreme circumstances.

Tracheitis

This can be diagnosed through

• Direct Laryngoscopy; This is used to view the voice box and upper part of the windpipe with the aid of a camera.
• Radiographic imaging

A lateral neck radiograph(x-ray) can confirm the diagnosis of bacterial tracheitis, which is suspected based on clinical presentation. It can also reveal purulent secretions and inflammation in the area below the vocal cords(subglottic area)with a shaggy, purulent membrane. The latter method can also reveal irregular subglottic narrowing, as opposed to the symmetric tapering (steeple sign) typical of croup. Direct laryngoscopy should only be performed under carefully monitored conditions where an artificial airway can be quickly created if needed.⁴

Management and treatment

Croup

• Opening a door or window at night will allow your youngster to breathe in cool air
• Use over-the-counter (OTC) medication to treat your child's fever, such as ibuprofen (Advil®) or acetaminophen (Tylenol®)
• Warm, clear liquids might relieve your child's cough by releasing mucus from their voice chords
• Refrain from smoking in your house since smoke aggravates your child's cough
• Using an additional cushion, keep your child's head raised
• Oxygenated air or humidity
• Intravenous liquids to treat dehydration
• Monitoring of respiration, heart rate, and oxygen levels, among other vital indications
• Medication for croup, such as nebulized breathing treatments (epinephrine) and steroids (glucocorticoids)
• Insertion of a mechanical ventilation breathing tube. This is not common.²

Tracheitis

• Ensuring a sufficient airway
• Antibiotics that work against streptococcal and S. aureus species

In severe cases, treatment for bacterial tracheitis is similar to that for epiglottitis; ideally, endotracheal intubation should be performed under controlled conditions by a medical professional experienced in maintaining the airway in children. The patient may require admission to the intensive care unit.

First-line antibiotics should be sensitive against streptococcal and methicillin-resistant S. aureus (MRSA) They include amoxicillin-clavulanic acid, ceftriaxone with nafcillin or vancomycin, clindamycin with a third-generation cephalosporin, or ampicillin-sulbactam. Following a conclusive microbiological diagnosis,  antibiotic coverage is restricted and should be maintained for at least ten days.⁴

Complications

Croup complications are not common. Less than 5% of children diagnosed with croup in most studies needed to be hospitalized, and less than 2% of those who were intubated. Roughly 0.5% of patients who were intubated died.

Pneumonia or bacterial tracheitis could arise from a subsequent bacterial infection.

Patients with croup have also been known to have

• Lymphadenitis(inflammation of the lymph nodes) 
• Otitis media(ear infection)
• Pneumothorax 
• Pulmonary oedema

Pneumomediastinum tracheitis

Some of the complications include:

• Respiratory distress syndrome
• Cellulitis
• Cardiopulmonary arrest
• Bleeding disorders(Disseminated Intravascular Coagulopathy)
• Death

Prognosis

For croup, there is a favourable prognosis and nearly invariably full recovery. Most patients can be effectively treated as outpatients and do not require hospital inpatient treatment. Hospitalization rates range from 1.5 to 30 per cent in most towns, with an average of 2.5 to 5 per cent. Hospitalizations in the United States during the 1990s averaged about 41,000 annually, although they seem to have declined since then. Intubation is not necessary for more than 2% of hospitalized children. The current croup treatment regimen, which combines steroids and nebulized epinephrine, may prevent the need for intubation. Although the precise death rate is unknown overall, 10-year research on intubated patients revealed a mortality rate of less than 0.5%.¹

In tracheitis, the severity of your child's disease and the speed at which they receive care will determine how well they do. Little children's airways can enlarge quickly, which makes breathing difficult for them. Your youngster may experience respiratory arrest and maybe pass away if their trachea is totally obstructed.

In addition, your child may experience toxic shock syndrome if S. aureus germs are the source of their infection. Fever, shock, organ failure, and even death may result from this illness.⁵

Differences

• Both croup and epiglottitis present similarly with bacterial tracheitis. Unlike croup, bacterial tracheitis typically manifests as a high fever and a child who loves sick
• Steroids and racemic epinephrine therapy are not working well for the patient. Compared to croup, the illness typically manifests with symptoms that last longer.⁶
• One distinguishing feature of croup is barking cough whereas in tracheitis only cough is present.
• Neck X-ray shows Steeple sign in both conditions
• Voice is hoarse in both cases
• Speed of onset is slow in croup and rapid in tracheitis³

Conclusion

Croup and bacterial tracheitis are both respiratory conditions, but they have distinct differences. Croup is typically viral and affects the upper airway, causing a barking cough and stridor, while bacterial tracheitis involves a bacterial infection of the trachea, leading to more severe symptoms like high fever and purulent secretions. Treatment and management strategies vary, with croup often managed conservatively and bacterial tracheitis requiring antibiotics and possibly airway intervention. Understanding these disparities is crucial for accurate diagnosis and effective treatment.