Evaluation of the Double Agar Gel Immunodiffusion Test and of the Enzyme-Linked Immunosorbent Assay in the Diagnosis and Follow-Up of Patients with Chronic Pulmonary Aspergillosis

Priscila Zacarias de Azevedo; Tatiane Fernanda Sylvestre; Ricardo de Souza Cavalcante; Lídia Raquel de Carvalho; Daniela Vanessa Moris; Maria Luiza Cotrim Sartor de Oliveira; Rinaldo Poncio Mendes

doi:10.1371/journal.pone.0134841

Evaluation of the Double Agar Gel Immunodiffusion Test and of the Enzyme-Linked Immunosorbent Assay in the Diagnosis and Follow-Up of Patients with Chronic Pulmonary Aspergillosis

PLoS One. 2015 Aug 13;10(8):e0134841. doi: 10.1371/journal.pone.0134841. eCollection 2015.

Authors

Priscila Zacarias de Azevedo¹, Tatiane Fernanda Sylvestre¹, Ricardo de Souza Cavalcante¹, Lídia Raquel de Carvalho², Daniela Vanessa Moris³, Maria Luiza Cotrim Sartor de Oliveira⁴, Rinaldo Poncio Mendes¹

Affiliations

¹ Tropical Diseases Department, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (UNESP), Botucatu, São Paulo State, Brazil.
² Instituto de Biociências de Botucatu, UNESP, Botucatu, São Paulo State, Brazil.
³ Universidade do Oeste Paulista, UNOESTE, Presidente Prudente, São Paulo State, Brazil.
⁴ Department of Pathology, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (UNESP), Botucatu, São Paulo State, Brazil.

Abstract

The diagnosis of chronic pulmonary aspergillosis (CPA) depends on the radiologic image and the identification of specific antibodies. The present study aimed to evaluate accuracy parameters of enzyme-linked immunosorbent assay (ELISA) and of the determination of serum galactomannan level in the diagnosis of patients with CPA, comparing these results with the double agar gel immunodiffusion (DID) test. In addition, the prevalence of cross-reactivity and the serological progression after treatment were evaluated by comparing DID and ELISA. Six study groups were formed: G1: 22 patients with CPA, 17 of whom had Aspergillus fungus ball, one chronic cavitary pulmonary aspergillosis (CCPA) and four chronic fibrosing pulmonary aspergillosis (CFPA); G2: 28 patients with pulmonary tuberculosis (TB); G3: 23 patients with histoplasmosis (HST); G4: 50 patients with paracoccidioidomycosis (PCM); G5: 20 patients with cryptococcosis (CRC); and G6: 200 healthy controls. Serum antibodies were measured by DID and ELISA, with two antigen preparations--Aspergillus fumigatus (DID1, ELISA1) and a pool of A. fumigatus, A. flavus and A. niger antigens (DID2, ELISA2). The Platélia Aspergillus Enzyme Immunoassay (EIA) kit was used to measure galactomannan. The cut-off points of ELISA were determined for each antigen preparation and for the 95% and 99% confidence intervals. Despite the low sensitivity, DID was the technique of choice due to its specificity, positive and negative predictive values and positive likelihood ratio-especially with the antigen pool and due to the low frequency of cross-reactivity. ELISA1 and a 0.090 cut-off showed high sensitivity, specificity and negative predictive value, but a high frequency of cross-reactivity with CRC. The best degree of agreement was observed between ELISA1 and ELISA2. The detection of serum galactomannan showed high sensitivity, comparable to ELISA2. The immunodiffusion test showed an excellent relationship with the progression after treatment, which made it the reaction of choice for patient follow-up.

Publication types

Clinical Trial
Comparative Study
Research Support, Non-U.S. Gov't

MeSH terms

Adult
Aged
Aged, 80 and over
Antigens, Fungal / blood*
Aspergillus*
Chronic Disease
Enzyme-Linked Immunosorbent Assay / methods
Female
Humans
Immunodiffusion / methods
Male
Middle Aged
Pulmonary Aspergillosis / blood*
Pulmonary Aspergillosis / diagnosis*

Substances

Antigens, Fungal

Grants and funding

The study was partially sponsored by the Coordenation for the Improvement of Higher Level Personnel – CAPES. No additional funding sources for this study.