Croup - Causes, Symptoms, Diagnosis, and Treatment

Introduction:

Croup is a common infection of the upper airways, causing breathing difficulty in infants and children. They are commonly seen between three months to five years of age and peak during the second year of life. Croup is generally a self-limiting disease with a spectrum that includes laryngotracheitis, laryngotracheobronchitis, and laryngo-tracheo-bronchopneumonitis. The breathing difficulty in croup is due to the swelling around the vocal cords, larynx, and trachea leading to stridor and barking cough.

What Does Stridor Mean?

Stridor is characterized by a high-pitched creaking or whistling sound during breathing. During a cough, the air is forced through the narrow airway passage, and the swollen vocal cords produce a high-pitched sound resembling a barking cough.

What Causes Croup?

Croup is commonly caused by viruses and, in some cases, also caused by bacteria.

A. The Virus That Causes Croup Are:

• Parainfluenza virus is a common cause and accounts for about 75 % of viral croup.

• Others are the adenovirus, influenza virus A and B, and respiratory syncytial virus (RSV).

B. The Bacterial Croup Is Divided Into:

• Laryngeal diphtheria.

• Bacterial tracheitis.

• Laryngotracheobronchitis.

• Laryngo-tracheo-bronchopnemonitis.

Laryngeal diphtheria is caused by Corynebacterium diphtheria. Bacterial tracheitis, laryngotracheobronchitis, and laryngo-tracheo-bronchopneumonitis begin as viral infections and get worse due to bacterial growth.

C. Other Common Bacteria Are:

• Staphylococcus aureus.

• Streptococcus pneumoniae.

• Hemophilus influenza.

• Moraxella catarrhalis.

How Does Your Child Get Infected With Croup?

Croup is spread through direct contact with an infected person. When your child breathes in the infected respiratory droplets that are coughed or sneezed into the air, the virus is contracted, and the infection follows. The infection starts in the nose and throat and then moves into the lungs, where it causes swelling around the larynx (voice box) and trachea (windpipe).

Who Is At High Risk?

• Generally, croup affects younger children between three months to five years of age.

• Peak incidence is seen at two years.

• Boys are more affected than girls.

• Most common in the winter.

Why Children Are Affected and Not Adults?

This is because, in younger children, the airways are smaller than in adults, so any swelling in the airway passage makes it hard to breathe.

What Exactly Happens in a Croup?

Soon after your child contracts the virus, the following events take place:

What Are Its Symptoms?

• A cough that sounds like barking or barking cough.

• Many children present with mild cold and low-grade fever. Sometimes fever may be absent, so suspecting the croup should not be avoided.

• Hoarse voice and trouble breathing.

• Agitation or nervousness worsens the croup.

• Croup worsens at night, lasting for five to six nights. The first two nights are the worst. It may improve in the morning and worsens as the day goes on.

What Are Some Other Conditions That Resemble Croup?

• Epiglottitis.

• Foreign body aspiration.

• Smoke inhalation.

• Peritonsillar and retropharyngeal abscesses.

How to Diagnose a Croup?

Diagnosis of croup is made clinically by the history presented to the doctor. Complete medical and physical examinations are required to rule out croup. An examination of the throat reveals red epiglottitis.

Other Tests Performed Are:

• Chest and Neck X-ray: To rule out narrowing of the trachea (steeple sign) or inhaled foreign objects.

• Blood Tests: In case of viral or bacterial infection.

• Pulse Oximetry: To find the amount of oxygen in the blood.

Can We Prevent Croup?

Yes, croup can be prevented by following a few basic protocols:

A) Good Hygiene Practices:

1. Frequent hand washing.

2. Keep your child away from anyone sick.

3. Teach your child to cough or sneeze into their elbows.

B) Vaccinations:

Vaccinations play a major role in preventing any serious infection, so keep a record of your child's immunization chart from birth. Immunization against influenza and diphtheria may reduce the incidence of croup.

What Are Some of the Home Remedies in Managing a Croup?

• Use a cool humidifier in your child's bedroom for two to three days until the croup goes away.

• Take your child out for a cool night's air.

• Provide them with a lot of fluids to stay hydrated.

• Calm your baby, as it may be easier for them to breathe.

• In case of fever, treat them with Acetaminophen (Paracetamol) or Ibuprofen as directed by the physician.

• Avoid cough medications containing Dextromethorphan or Guaifenesin.

• Do not give Aspirin. The use of Aspirin is always contraindicated in children as it may cause Reye syndrome. It is a serious condition that causes swelling of the brain and liver damage.

When to See Your Doctor?

• When the home remedies do not work out, the child looks more agitated.

• A child struggling to breathe with stridor.

• When the skin color and lips turn blue, immediately seek medical assistance.

What Are Westley's Scoring Criteria?

The Westley scoring criteria are used to assess the severity of croup ranging from a score of 0 to 17. This is based on five factors. They are,

A) Inspiratory Stridor:

• 0 - None.

• 1 - When agitated.

• 2 - At rest.

B) Retractions:

• 0 - None.

• 1- Mild.

• 2 - Moderate.

• 3 - Severe.

C) Air Entry:

• 0 - Normal.

• 1- Decreased.

• 2 - Markedly decreased.

D) Cyanosis:

• 0 - None.

• 4 - When crying.

• 5 - At rest.

E) Loss of Consciousness:

• 0 - Alert.

• 5 - Disoriented.

Mild Croup: When the score is less than or equal to two.

Moderate Croup: Score between three to five.

Severe Croup: Score values between 6 to 11.

Respiratory Failure: More than 12.

What Is the Treatment for Croup?

The treatment plan varies for each child and is based on the Westley croup scoring criteria. 85 % of children present with mild cases.

• Mild Cases ⇒ Treated with a single dose of Dexamethasone (steroid).

• Moderate to Severe Cases ⇒ Nebulized Epinephrine plus Dexamethasone and supplemental oxygen for children with decreasing oxygen saturation.

When Is Intubation Required?

In severe cases, rarely do children require endotracheal intubation to maintain the patent airflow in case of swelling and obstruction.

What Are the Medications Used in Croup?

Steroids :

• Corticosteroids such as Dexamethasone result in a faster recovery rate.
• Administered through oral or inhaled route.
• Dosage: 0.15/kg, 0.3 mg/kg, 0.6 mg/kg (commonly used).

Epinephrine:

• Racemic Epinephrine improves the symptoms within 30 minutes of administration but wears off after two hours.
• 0.5 ml/kg of L. Epinephrine 1:1000 through a nebulizer is more effective than racemic Epinephrine.
• Four hours of observation are required after Epinephrine administration, and if the symptoms do not improve, admission is required.

Antibiotics:

• Since croup is commonly caused due to viruses, antibiotics are indicated for primary and secondary bacterial infections.
• Vancomycin, Cefotaxime - For secondary bacterial infection.
• Antiviral neuraminidase - Influenza A and B infections.

Conclusion:

Croup is a self-limiting condition that can be resolved within three to five days itself and does not require hospitalization. Only in a few cases may the child need a doctor's visit if there is any airway obstruction causing breathing difficulties. Comforting your baby by singing soft songs to them helps them in overcoming agitation and makes them easy to breathe. Following a hygienic lifestyle and proper immunization can further prevent croup in your baby.