LARYNGOTRACHEOBRONCHITIS, CROUP, AN UNUSUAL PRESENTATION OF SARS-COV-2.

Editor

Laryngotracheobronchitis or croup, whilst common in childhood, is rare in adults. We present an unusual clinical presentation of infection with Sars-COV-2, COVID-19 Laryngotracheobronchitis.

A 52-year-old female presented to the Emergency Department with a three day history of progressive fatigue, hoarseness and dysphagia. On examination she was sitting forward, breathing quietly, aphonic and drooling. She had mild bilateral cervical lymphandenopathy. Flexible nasendoscopy showed mild supraglottic oedema and erythema, but no airway compromise. Chest xray demonstrated “steeple sign” (Figure 1) indicative of laryngotracheobronchitis or “croup.”

Figure 1

Erect Chest X-ray of the patient demonstrating the typical “steeple sign associated with laryngotracheobronchitis

She had a mild inflammatory response demonstrated by a C-Reactive Protein of 15mg/L. There were no symptoms to necessitate a COVID-19 test had she not attended hospital, however her polymerase chain reaction (PCR) for SARS-CoV-2 resulted positive, with viral PCR for Influenza A & B, and Respiratory Syncytial Virus (RSV) all negative. The presumed diagnosis was of COVID-19 Laryngotracheobronchitis. Treatment was supportive, in the form of intravenous fluids, humidified oxygen and intravenous corticosteroids to reduce airway oedema. Following 24 hours the patient improved clinically, and flexible nasoendoscopy revealed resolution of supraglottic oedema. The patient was discharged with a five day course of oral dexamethasone.

Laryngotracheobronchitis, commonly referred to as croup, is an upper respiratory tract infection, almost exclusively seen in the paediatric population. It commonly presents with fever, “barking” cough, stridor, dyspnoea, and hoarseness. Adult croup is more severe than in the paediatric cohort, and often requires aggressive treatment and longer hospital stays1. Direct evidence of oedema, and the typical “steeple sign” feature on x-ray, which represents subglottic narrowing, is more commonly found in adults1. The most common pathogen amongst children is Parainfluenza virus type-1, however RSV and adenovirus are also commonly isolated2. In adults culprit organisms leading to croup include Parainfluenza, Haemophilus influenziae, Influenza, Streptococcus, and RSV1. Mainstay therapy is guided by severity of symptoms. Humidified oxygen, corticosteroids and nebulised adrenaline are all recommended in moderate to severe croup in children. In adults there are no formal recommended treatments, however all reported cases have used a combination of treatments recommended in paediatric croup.

COVID-19 infection, caused by SARS-CoV-2 virus has infected over 200 million people, resulting in over 4 million deaths worldwide to date. The majority of healthy individuals are thought to remain asymptomatic, however those presenting with symptoms related to COVID-19 typically experience fever, cough, and loss of taste and smell. In more severe cases respiratory compromise may occur, requiring invasive respiratory support. There is very little evidence in the literature of upper airway oedema related to infection with COVID-19, with only 4 reports of croup in COVID-19 positive children3,4. To date there are only two documented cases of COVID-19 related laryngotracheobronchitis in adults5. Despite the relatively indolent clinical course of the patient herein described, timely diagnosis and early intervention could prove to be critical in preventing airway compromise in patients presenting with COVID-19 infection of the upper respiratory tract.