Immunoprecipitation techniques and Elisa in the detection of anti-Fonsecaea pedrosoi antibodies in chromoblastomycosis

Abstract

SUMMARYChromoblastomycosis (CBM) is a chronic subcutaneous infection caused by several dematiaceous fungi. The most commonly etiological agent found in Brazil is Fonsecaea pedrosoi, which appears as thick walled, brownish colored cells with transverse and longitudinal division in the lesions, called "muriform cells". This disease is found worldwide but countries like Madagascar and Brazil have highest incidence. Diagnosis is made by clinical, direct and histopathologic examination and culture of specimens. Serological tests have been used to identify specific antibodies against Fonsecaea pedrosoi antigens, as well as immunotechniques have been used for CBM serological identification and diagnosis. In the present study double immunodiffusion (DID), counterimmunoelectrophoresis (CIE) and immunoenzymatic test (ELISA) have been used to evaluate humoral immune response in patients with CBM caused by F. pedrosoi. Metabolic antigen was used for immunoprecipitation tests (DID and CIE) while somatic antigen for ELISA. Our results demonstrated 53% sensitivity and 96% specificity for DID, while CIE presented 68% sensitivity and 90.5% specificity. ELISA demonstrated 78% sensibility and 83% specificity. Serological tests can be a useful tool to study different aspects of CBM, such as helping differential diagnosis, when culture of the pathogenic agent is impossible.

Melanized Fungi in Human Disease

“…Further studies are needed to better understand the nature and likelihood of cross-reactivity. Serum enzyme-linked immunosorbent assays (ELISAs) for F. pedrosoi and C. carrionii have been developed to aid in the diagnosis of chromoblastomycosis, though relatively low sensitivity and specificity have limited their usefulness, and only small numbers of patients have been studied (552,775,778).…”

Use of Mycelial-Phase Sporothrix schenckii Exoantigens in an Enzyme-Linked Immunosorbent Assay for Diagnosis of Sporotrichosis by Antibody Detection

“…At present, the detection of host antibodies to S. schenckii is accomplished by immunoelectrophoresis and tube agglutination (1,16). Although several new immunoassays have been developed for the detection of antibodies in the serum samples of patients with histoplasmosis (10,26), paracoccidioidomycosis (2,21), chromoblastomycosis (9,34), and candidiasis (17), there is a paucity of effective immunoassays for the serodiagnosis of sporotrichosis. In addition, these immunoassays involve laborious antigen production procedures (6,30).…”

Accuracy of direct examination and culture as compared to the anatomopathological examination for the diagnosis of chromoblastomycosis: a systematic review

“…In total, the 11 studies included 764 patients, 152 with chromoblastomycosis and 612 without the disease (healthy patients or patients with other mycoses such as sporotrichosis, paracoccidioidomycosis, or mycetoma). 12 , 13 , 14 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 Two studies assessed the same sample of patients, testing different serological methods in each of them. 31 , 32 The studied patients were from India, China, Japan, Brazil, and Costa Rica.…”

“… 12 , 13 , 14 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 Two studies assessed the same sample of patients, testing different serological methods in each of them. 31 , 32 The studied patients were from India, China, Japan, Brazil, and Costa Rica. The participants characteristics are summarized in Table 1 , and the methodological characteristics of the studies are shown in Table 2 .…”

“…Additionally, studies that evaluated the diagnostic accuracy of serology used controls with a previously known diagnosis (healthy patients or patients with other mycoses), which represents a selection bias risk. 1 , 12 , 13 , 30 , 31 , 32 …”