Defining atypical croup: A case report and review of the literature

BACKGROUND: Croup is a common respiratory illness in children. It presents with a barky cough, stridor and hoarseness occurring secondary to inflammation of the subglottis and larynx. The clinical course of croup is well-described, however atypical presentations pose a diagnostic and management challenge. OBJECTIVES: This case report and systematic review aims to synthesize the published literature on the definition, diagnosis and treatment of atypical croup. STUDY SELECTION: Peer-reviewed journal publications in Ovid MEDLINE® and EMBASE from inception to January 1, 2019 in English, focusing on pediatric patients (<18 years of age) with diagnoses of atypical croup. DATA EXTRACTION: Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: Twelve studies involving 670 patients ranging from 6 months to 11 years of age presenting with atypical croup were selected. A variety of definitions of atypical croup were identified based on recurrence, duration of symptoms, severity, and etiology. Data on the incidence of atypical croup, the overall rates of intubation and tracheostomy, and patient characteristics leading to definitive airway management were not clearly characterized. LIMITATIONS: All studies were case series, case reports or retrospective chart reviews. CONCLUSIONS: Atypical croup is a poorly defined clinical entity that is used to describe recurrent, refractory, or croup-like illness that follows an uncharacteristic natural history. Our case presentation and accompanying literature review highlights the variable, but limited, information available on the diagnosis of atypical croup. Given the commonality of its use in clinical practice, we propose some guidelines around the use of the term ‘atypical croup’ as well as a management algorithm.