Specificity and sensitivity of the reagent Platelia Aspergillus IgG (BIO-RAD) with recombinant proteins

Mr. DautignyS. Le CamO. CornetTD Ly

Abstract: 

Aspergillosis are essentially related lung disease most often at Aspergillus fumigatus. They affect immunocompetent individuals (aspergilloma, allergic aspergillosis) as well qu'immunodéprimés. In immunocompetent patients, the diagnosis is made by mycological research associated with the determination of Aspergillus serology (IgG). Serological diagnosis is carried out in 2 phases: a screening sensitive technique (ELISA mostly), if positive confirmation by a reference type immunoelectrophoresis technique (IEP) or coélectrosynérèse.

Purpose of the study: The new reagent Platelia Aspergillus IgG (Biorad, Marnes la coquette, France), using recombinant proteins was compared with the IEP reference technique, in parallel with the Aspergillus fumigatus IgG ELISA reagent (IBL, Hamburg , Germany), routinely used in our laboratory.

Methods: 306 routine samples not selected, were tested with the 3 tests. ELISA assays (Platelia and IBL) were performed on the ETIMAX controller.

FPI is performed using the extracted antigens of Aspergillus fumigatus (Biorad), agarose gel (SEBIA).

Results: The results (excluding impaired results) are summarized in the tables below:

Table I: Platelia versus IEP

IEP Aspergillus fumigatus IgG (Bio Rad)    
  Negative Doubtful Positive
Negative 184 6 12
doubtful 29 4 14
Positive 4 2 51

Platelia sensitivity of 92.7% and specificity 93.8%; 94% overall concordance

Table II: IEP versus IBL

IEP Aspergillus fumigatus IgG (IBL)    
  Negative Doubtful Positive
Negative 107 32 63
doubtful 8 4 35
Positive 11 2 44

IBL sensitivity 80% and specificity 63%; 67% overall concordance

Conclusion: The ELISA IgG Platelia Aspergillus first reagent using the recombinant proteins, has excellent sensitivity (92.7%) and good specificity (93.8%) in the detection of aspergillus serology. This test has fewer false positives than IBL and its specificity can detect patients who are positive for IEP.

2010

Full conference title: 

Réunion Interdisciplinaire de Chimiothérapie Anti Infectieuse
    • RICAI 30th (2010)