What virus causes laryngotracheobronchitis (croup)?

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From the Research

Croup is primarily caused by the parainfluenza virus, which accounts for approximately 75% of infections, as reported in the most recent and highest quality study 1. The parainfluenza virus, particularly types 1 and 2, is the most common cause of croup, a condition characterized by inflammation and swelling of the vocal cords and surrounding tissues, leading to a barking cough, stridor, and respiratory distress. Other viruses that can cause croup include respiratory syncytial virus (RSV), influenza viruses, adenoviruses, and human metapneumovirus. The condition most commonly affects children between 6 months and 3 years of age, with symptoms typically worsening at night. Key points to consider in the management of croup include:

  • The use of corticosteroids, such as dexamethasone, to reduce the severity of symptoms and the need for hospitalization, as supported by studies 1, 2
  • The administration of nebulized epinephrine in severe cases to provide symptomatic relief, as recommended in the literature 1, 3
  • The importance of supportive care, including cool mist and humidification, to help manage symptoms and improve patient comfort. It is essential to note that most cases of croup are mild and resolve within 3-7 days as the viral infection runs its course, though the barking cough may persist longer, as indicated in the study 1.

References

Research

Croup.

BMJ clinical evidence, 2014

Research

Viral croup: a current perspective.

Journal of pediatric health care : official publication of National Association of Pediatric Nurse Associates & Practitioners, 2004

Research

New approaches to respiratory infections in children. Bronchiolitis and croup.

Emergency medicine clinics of North America, 2002

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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