Suspected early Aspergillus-related allergic airway disease with bacterial co-detection in a child with refractory...

Allergic bronchopulmonary aspergillosis (ABPA) is under-recognized in children with refractory asthma and may be obscured by concurrent respiratory infections. We describe a 10-year-old girl with poorly controlled asthma admitted with fever, productive cough, and wheezing. Investigations revealed marked peripheral eosinophilia (1.48 × 10⁹/L), markedly elevated total immunoglobulin E (1742 IU/mL), positive bronchoalveolar lavage (BAL) galactomannan, and positive BAL Aspergillus antigen. Multiplex respiratory polymerase chain reaction (PCR) detected Streptococcus pneumoniae, Haemophilus influenzae, and methicillin-resistant Staphylococcus aureus, whereas concurrent bacterial cultures, blood culture, fungal culture, and viral testing were negative. High-resolution chest computed tomography (HRCT) demonstrated diffuse ground-glass opacities and bronchial wall thickening without central bronchiectasis or mucus plugging. A. fumigatus-specific IgE was not available, precluding formal classification under contemporary diagnostic criteria. A. fumigatus IgM and IgG were positive on follow-up serology. After empirical antibacterial therapy with limited durable response, oral itraconazole was initiated with sustained clinical improvement, declining total IgE and eosinophils, and stable hepatic function. This presentation is best characterized as suspected early Aspergillus-related allergic airway disease rather than confirmed ABPA. The case highlights three lessons for infectious diseases clinicians: bacterial co-detection by multiplex PCR may anchor reasoning toward infection and delay recognition of allergic fungal airway disease; lower airway Aspergillus biomarkers are supportive but not diagnostic; and the absence of central bronchiectasis does not exclude early disease. Integrated clinical, immunologic, microbiologic, and radiologic reasoning is essential in pediatric refractory asthma.