The value of an enzyme-linked immunosorbent assay for the diagnosis of schistosomiasis mansoni myeloradiculopathy

Abstract

The role of serological tests on cerebrospinal fluid (CSF) in the diagnosis of neuroschistosomiasis has not been fully elucidated; the condition is essentially diagnosed on the basis of circumstantial evidence, which may lead to an erroneous diagnosis, especially in highly endemic areas. We therefore carried out a prospective case-control study in which we compared the concentrations of immunoglobulin G (IgG) specific for schistosome soluble egg antigen (SEA) present in the CSF of 54 patients with schistosomiasis mansoni myeloradiculopathy (SMMR) with those observed in a control group consisting of 41 patients with epidemiological and serological evidence of exposure to schistosomes, and with other neurological disorders that result in mild to moderate impairment of the blood-brain barrier. Anti-SEA IgG was estimated by an enzyme-linked immunosorbent assay. The sensitivity, specificity and positive and negative predictive values were 56%, 95%, 94% and 62% respectively. Likelihood ratios and the corresponding post-test probabilities were determined for 4 levels of anti-SEA IgG in CSF. A value below 0.1 micrograms/mL practically excluded the possibility of SMMR (post-test probability < 5%), a value above 1.4 micrograms/mL practically confirmed the diagnosis of SMMR (post-test probability > 96%), values of 0.1 to 0.5 microgram/mL had no diagnostic value (post-test probability approximately 45%), and values of 0.6 to 1.4 micrograms/mL were useful in some situations (post-test probability approximately 70%). We conclude that the estimation of anti-SEA IgG in the CSF is useful for the diagnosis of SMMR.

Esquistossomose medular: análise de 80 casos

“…O LCR é fiel sinalizador destas reações inflamatórias expressadas, entre outros sinais, pela eosinofilorraquia observada em 90% dos nossos casos e pela positividade das reações imunológicas específicas para esquistossomose podendo ser acompanhada de síntese intratecal de imunoglobulina G 13,29,30,31,33,36 .…”

Clinical-epidemiologic profile of the schistosomal myeloradiculopathy in Pernambuco, Brazil

“…In this hospital, serum and/or cerebrospinal fluid from 95 out of the 100 patients with SMR were investigated for the presence of antibodies against Schistosoma antigens using the ELISA technique, from whom only 37 presented reactive results. Other studies have shown the promising potential of serological tests on cerebrospinal fluid for diagnosing this entity , Ferrari et al 1995, Ferrari 1997. However, these tests need to be validated and standardized.…”

Update on Eosinophilic Meningoencephalitis and Its Clinical Relevance

“…ELISA performed with soluble egg antigen (SEA) is the more reliable immunological method for diagnosis of NSM, with 56% sensitivity and 95% specificity (95). Although more purified preparations and defined antigens have been reported, they have not been extensively tested for diagnosis of NSM (81, 234 Antibody detection methods are not considered useful in areas of endemicity, because these areas contain a large number of serologically positive but not diseased individuals (36).…”