Introduction

Croup and laryngomalacia are two respiratory illnesses that typically affect babies and children. Even though these are two different conditions, they share several similarities that we will discuss in this article. In general, they both cause noisy sounds called stridor when your little one breathes in. However, the underlying cause, other associated symptoms, and treatment approaches between them are different. 

What is croup?

Croup is a respiratory illness that is typically caused by a viral infection, most often the parainfluenza virus. It can also be caused by a bacterial infection in rarer cases. The incidence of this disease is higher in the age group of six months to three years. 

Croup causes your baby’s trachea, larynx, and bronchi to swell and become inflamed. First, let’s understand the function of these body parts. 

The larynx is the area of your throat that contains the vocal cords and is used for breathing, swallowing, and talking. The trachea is a long tube that connects the larynx to the lungs. It is connected to the lung through bronchi, which also serves as an air passage. 

The swelling and narrowing of these respiratory tracts result in airway obstruction. When the obstruction is significant, it leads to a noisy sound during breathing due to air turbulence and increased breathing force. This is called stridor. When your child has croup, they may also show other symptoms including a seal-like barking cough, hoarse voice, a high-pitched rasping sound when inhaling, and difficulty breathing which may worsen at night. Other symptoms that may also be present include cold-like symptoms such as fever and a runny nose.

Most croup cases can be treated at home as they are self-limiting diseases. However, in moderate and severe cases, they may need to be hospitalised and receive medications like corticosteroids and epinephrine.^1,2

What is laryngomalacia?

Laryngomalacia is a congenital condition, meaning a baby is born with it. It causes the soft tissues of the larynx to be floppy and malformed, making it collapse inward during inhalation and partially block the airway. This structural vulnerability leads to intermittent airway obstruction. Despite many theories being proposed, the exact cause of this abnormality is unknown.

If your child has laryngomalacia, symptoms may be present at birth and can become more obvious within a few weeks of life. The main symptom is noisy breathing (stridor), which worsens when your baby is feeding, crying, agitated, or sleeping on their back. They may also have poor weight gain, choke while being fed, produce a high-pitched sound, experience apnoea (temporary cessation of breathing), spit up and vomit, and turn blue (cyanosis). The food they eat may also be inhaled into the lungs, causing aspiration.

In most cases, laryngomalacia will resolve as the child grows, usually by the age of 18 to 20 months. The laryngeal structure will mature and does not require intervention like surgery. However, some cases may need medical intervention to relieve the symptoms and ensure the child can breathe adequately.^3,4

Similarities between croup and laryngomalacia

Who they affect

Both conditions primarily affect babies and young children. While laryngomalacia is present at birth, croup can affect infants and children with the highest incidence between six months to three years. 

Symptoms

Noisy breathing (stridor)

Both croup and laryngomalacia patients produce stridor while breathing. In croup, the stridor is caused by the swelling and narrowing of the air passage, while in laryngomalacia, the soft and floppy larynx tissue causes the airway to collapse during inspiration, leading to airflow turbulence. 

There are also similarities in factors that worsen the stridor. Stridor in laryngomalacia will exacerbate when the baby is feeding, agitated, crying, or lying on their back. In croup, stridor will worsen when the baby is exposed to conditions that increase swelling, such as night-time and agitation. Additionally, stridor in croup is often accompanied by a barking cough.

Breathing difficulty

Patients with both conditions can possibly experience breathing difficulty as they both affect the air passage. This condition can be noticed from signs such as retraction on their chest, their belly moving, and others.

Hoarseness

Viral infection in croup causes hoarse voice because it affects the respiratory tract including the larynx which is the place for your vocal cords. Children often have hoarse voices along with stridor and barking cough. In laryngomalacia, a hoarse cry is also common.^3,5

Management

Both conditions require prompt diagnosis and treatment. They share similarities in that some cases can be resolved on their own, while others need medical intervention. However, there are key differences in the management approaches of croup and laryngomalacia.

Croup is mainly caused by a viral infection and, often, only supportive care is needed for recovery. It typically resolves on its own without medication within a few days to weeks. In severe cases, hospitalisation and medications such as steroids and epinephrine may be necessary to reduce inflammation.

Laryngomalacia, on the other hand, takes longer to resolve. It can take 18 to 20 months for the laryngeal structure to mature and stop causing airway collapse. Some cases may require medication and surgery. Common surgical procedures for laryngomalacia include supraglottoplasty and epiglottopexy, or a combination of these techniques.^1,6

When to see a doctor

Both conditions pose a risk of difficulty breathing and other respiratory issues. Try to recognise when the baby is having alarming symptoms. Go seek medical help if your baby is showing these symptoms:

• Very high fever (in croup)
• Look very unwell and are drowsy or restless
• Retraction on their chest
• Abnormal belly movement (tummy sucking under their ribcage)
• Ethargy
• Skin turning blue which can indicate respiratory distress
• Stops breathing for more than 10 seconds (apnoea)

As parents, having a baby with these symptoms can make you feel constantly worried, especially when they are frequently making stridor sounds. It's important to understand that sometimes, despite the stridor, they can still breathe normally. However, be vigilant for signs of respiratory distress or failure to thrive, which require immediate medical attention.^7,8

FAQs

What can be misdiagnosed as croup?

Croup is often misdiagnosed as epiglottitis. Epiglottitis is an inflammation of the epiglottis, a flap tissue beneath your tongue, caused by infection or injury. It shares the same manifestations with croup including stridor, difficulty breathing, and hoarse voice. Other conditions that share similarities and can be misdiagnosed as croup are bacterial tracheitis, foreign body aspiration, hemangioma, and airway lesion.^2,9

Is laryngomalacia the same as croup?

No, they are different illnesses. Croup is mainly caused by viral infections that lead to swelling of the respiratory tract. Laryngomalacia, on the other hand, is a condition that develops when the baby is born. Their laryngeal tissue is soft and floppy, causing it to collapse over the airway.

Even though they are different, they share similarities in terms of symptoms, including stridor and breathing difficulty.

What are the long-term effects of laryngomalacia?

Most cases of laryngomalacia go away on their own without treatment by the time the child is 18 months old. However, during this period, they may experience complications such as respiratory distress and feeding difficulties, leading to failure to thrive. In the long term, if they resolve or are treated as necessary, they usually don’t cause any problems. However, a small number of children may develop breathing problems that require further treatment or surgery.

What is laryngomalacia linked to?

There is a link between laryngomalacia and gastroesophageal reflux disease. Even though reflux is common in babies in general, a baby with laryngomalacia is more likely to experience it. This reflux is associated with their laryngeal structure and swallowing issues.⁴

Summary

• Croup is a respiratory tract infection, mainly caused by the parainfluenza virus. It leads to swelling and narrowing of the airway.
• Laryngomalacia is a congenital condition where your baby’s larynx is soft and floppy, causing it to fall over the airway and temporarily block the passage of air, leading to air turbulence.
• The similarities between croup and laryngomalacia lie in their manifestation. Both conditions cause stridor and breathing difficulty, along with other symptoms such as a hoarse voice and worsened stridor with agitation or crying. Additionally, croup and laryngomalacia commonly occur in infants and young children and can resolve on their own, but in some cases, they require medical treatment.
• Despite these similarities, the underlying causes and management approaches differ significantly