Immunoassays as an auxiliary tool for the serodiagnosis of Schistosoma mansoni infection in individuals with low intensity of egg elimination.
In an attempt to improve the screening of Schistosoma mansoni-infected individuals from a low-transmission area, we established a protocol that includes three independent coproscopy examinations and two serological assays. Three stool samples were examined using the Kato-Katz and free sedimentation methods and serum samples were tested by IgG-ELISA and IgM-immunofluorescence. Two hundred and sixty-nine individuals participated in the survey: 132 individuals (49%) showed positive serological test results. Of these, 16 (6%) had positive results in stool examination in the first sample batch. However, there were also cases with positive serological test results in spite of negative Kato-Katz stool examinations. Additional stool samples were obtained from these subjects and in this way an additional 11 egg-excretors were found. Our findings suggest that a screening method that combines antibody isotype detection and repeated parasitological stool examinations could increase the chances of detecting S. mansoni-infected patients.
Gonçalves
Margareth M L
MM
Departamento de Imunologia, Instituto de Microbiologia Professor Paulo de Góes-CCS, Universidade Federal do Rio de Janeiro, 21941590 Rio de Janeiro, Brazil.
Barreto
Magali G M
MG
Peralta
Regina H S
RH
Gargioni
Cybele
C
Gonçalves
Tiana
T
Igreja
Ricardo P
RP
Soares
Marisa S
MS
Peralta
José M
JM
D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood*; D000947:Antigens, Helminth / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005243:Feces / Q000469:parasitology*; D005455:Fluorescent Antibody Technique; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D010270:Parasite Egg Count; D012550:Schistosoma mansoni / Q000254:growth & development / Q000276:immunology* / Q000302:isolation & purification; D012555:Schistosomiasis mansoni / Q000175:diagnosis* / Q000469:parasitology; D012698:Serologic Tests
D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D007074:Immunoglobulin G; D007075:Immunoglobulin M