Petit E., Cortaredona Sébastien, Sicco S., Ranque S., Menu E. (2025). Combined immunoCAP and western blot for the diagnosis of Aspergillus lung disease. Mycoses, 68 (4), p. e70058 [9 p.]. ISSN 0933-7407.
Titre du document
Combined immunoCAP and western blot for the diagnosis of Aspergillus lung disease
Petit E., Cortaredona Sébastien, Sicco S., Ranque S., Menu E.
Source
Mycoses, 2025,
68 (4), p. e70058 [9 p.] ISSN 0933-7407
Background: Pulmonary aspergillosis is a major global health concern, yet its diagnosis remains challenging. Aspergillus-specific IgG measurement is essential for identifying chronic and allergic forms. Objective: This study aimed to evaluate a quantitative method, the ImmunoCAP assay IgG m3 (ICAP) (Phadia-ThermoFisher Scientific, Waltham, USA), a qualitative method, the Aspergillus IgG Western blot kit (Asp-WB) (LDBio Diagnostics, Lyon, France) and a combination of both methods for the diagnosis of Aspergillus lung disease. Methods: A retrospective study was conducted at the University Hospital of Marseille, France, during 1 year. Patients undergoing Aspergillus serology were divided into three groups: Group 1 (G1) with ICAP >= 40 mgA/L and positive Asp-WB, Group 2 (G2) with ICAP >= 40 mgA/L and negative Asp-WB and Group 3 (G3) with ICAP < 40 mgA/L and positive Asp-WB. Data were collected on demographics, underlying diseases, imaging and biological outcomes. Patients were classified according to their Aspergillus lung disease, whether acute pulmonary aspergillosis, chronic pulmonary aspergillosis (CPA), allergic broncho-pulmonary aspergillosis (ABPA), colonisation or Aspergillus sensitisation. Results: A total of 536 patients were studied: 173 in G1, 204 in G2 and 200 in G3, with 38 patients found in several groups. The primary underlying disease was cystic fibrosis in 44.6% of patients. Twenty-two patients were diagnosed with ABPA. The number of diagnosed ABPA cases in G1 (20; 11.6%) combining positive ICAP and Asp-WB was significantly higher than that found in the groups with a single positive test result (p < 0.001). Fifteen patients were diagnosed with CPA. Isolated positive Western blot (G3) identified five cases of aspergilloma. Significantly fewer Aspergillus lung diseases were diagnosed in isolated positive ICAP G2 (8.8%) than in G1 (53.8%) and G3 (42.5%) (p < 0.001). Conclusions: This study highlights the benefits of combining Asp-WB and ICAP for the diagnosis of Aspergillus lung disease and the relatively high false-positive rate in patients with isolated positive ICAP results.
