Need to re‐look cut‐off of Aspergillus‐specific IgE levels in children with ABPA

Abstract

Summary The cut‐offs for total and specific IgE used for diagnosing ABPA in children have been adopted from adult literature and have not been validated in the paediatric population. To establish the ideal cut‐offs of total IgE and Aspergillus‐specific IgE for the diagnosis of ABPA in children. This study was a prospective observational case‐control study, conducted in a tertiary care hospital in North India, enrolling 140 children with partly controlled and uncontrolled asthma. Seventy children had ABPA based on the Rosenberg‐Patterson Criteria (Cases) whereas 70 children were without ABPA (Controls). All children were subjected to clinical examination and investigations such as absolute eosinophil count, total IgE, Aspergillus‐specific IgE, Aspergillus skin prick test and radiological tests. ROC curve analysis was done to determine the ideal cut‐offs of total and specific IgE to diagnose ABPA. The ROC curve analysis determined 1204IU/L as the cut‐off value of total IgE with a sensitivity of 79.7% (95%CI 68.31% to 88.44%) and specificity of 53.1% (95%CI 40.23 to 65.7). The ROC analysis of specific IgE levels of children with ABPA determined the cut‐off value of 0.49 KAU/L with a sensitivity of 94.03% (95%CI 85.41 to 98.35) and specificity of 88.89% (95%CI 75.94% to 96.29%). We propose that the cut‐offs of total and specific IgE need to be relooked in the paediatric population. Cut‐offs of total IgE as 1204 IU/L and for Aspergillus‐specific IgE as 0.49KAU/L seem appropriate. Large multicentric studies should be conducted to determine the ideal values for diagnosing paediatric ABPA.

Epidemiology and outcomes of allergic bronchopulmonary aspergillosis in the elderly

“…Whether certain unknown environmental or genetic factors influence the development of ABPA in elderly Japanese patients remains speculative.What are the clinical implications of our study? It is of great clinical value to delineate a disease's natural history and course in specific subgroups, including children, pregnancy, the elderly and others 39,40. Our results suggest that elderly patients with ABPA have a less severe immunological and radiological disease and possibly better outcomes than the young.…”

Fungal sensitization and positive fungal culture from sputum in children with asthma are associated with reduced lung function and acute asthma attacks respectively

“…18,19 Adults with severe asthma and fungal sensitization frequently harbour fungi in the airways, supporting the hypothesis of a mechanistic link between fungal sensitization and airway colonization. 20 The role of fungi in asthma is increasingly recognized as a spectrum, ranging from the somewhat rigid and arbitrary criteria for Allergic Bronchopulmonary Aspergillosis/Mycosis (ABPA/ABPM) [21][22][23] to more 'umbrella-like' terms such as severe asthma with fungal sensitization (SAFS) in adults, 24 fungal asthma in children 25 or Allergic Fungal Airway Disease (AFAD). 16,26 There are subtle differences between these labels, broadly separated by the level and relevance of total IgE cut-off values.…”

“…The diagnostic label ‘severe asthma with fungal sensitization’ (SAFS) is used for adults with severe asthma who do not fulfil the criteria for ABPA, in particular those with a total serum IgE below 1000 IU/L 24 . There are no defined and universally accepted criteria for ABPA 21 and SAFS in children. A study in children with severe asthma and sensitization to fungi without ABPA found higher total IgE values in sensitized children, greater frequency of maintenance oral steroids and higher sputum IL‐33 levels 29 …”