title: IgM quantification in the cerebrospinal fluid of sleeping sickness patients by a latex card agglutination test.
abstract: An increased IgM concentration in cerebrospinal fluid (CSF), occurring as a consequence of massive intrathecal IgM synthesis, is a marker of interest for diagnosis of the meningo-encephalitic stage in human African trypanosomiasis. However, in current practice, IgM in CSF is not determined because of the lack of a simple and robust test that is applicable in African rural regions where the disease prevails. We describe the development of a sensitive semiquantitative card agglutination test, LATEX/IgM, for IgM quantification in CSF. The test is simple and fast and the lyophilized reagent remains stable even at 45 degrees C. CSF end-titres obtained with LATEX/IgM parallel the IgM concentrations determined by nephelometry and enzyme-linked immunosorbent assay. Detection of intrathecal IgM synthesis is the most sensitive marker for CNS involvement in sleeping sickness. At a cut-off value of >or= 8, the sensitivity and specificity of LATEX/IgM for intrathecal IgM synthesis are 89.4 and 92.7%. As a consequence, patients with LATEX/IgM end-titres >or= 8 are likely to have intrathecal IgM synthesis, thus central nervous system involvement and therefore should be treated accordingly. Further studies should concentrate on the relationship between the LATEX/IgM end-titres, presence of intrathecal IgM synthesis and occurrence of treatment failures in patients treated with pentamidine.
authors.affiliation: Department of Parasitology, Institute of Tropical Medicine, Antwerpen, Belgium. vlejon@itg.be
authors.forename: V
authors.initials: V
authors.lastname: Lejon
authors.forename: D
authors.initials: D
authors.lastname: Legros
authors.forename: M
authors.initials: M
authors.lastname: Richer
authors.forename: J A
authors.initials: JA
authors.lastname: Ruiz
authors.forename: V
authors.initials: V
authors.lastname: Jamonneau
authors.forename: P
authors.initials: P
authors.lastname: Truc
authors.forename: F
authors.initials: F
authors.lastname: Doua
authors.forename: N
authors.initials: N
authors.lastname: Djé
authors.forename: F X
authors.initials: FX
authors.lastname: N'Siesi
authors.forename: S
authors.initials: S
authors.lastname: Bisser
authors.forename: E
authors.initials: E
authors.lastname: Magnus
authors.forename: I
authors.initials: I
authors.lastname: Wouters
authors.forename: J
authors.initials: J
authors.lastname: Konings
authors.forename: T
authors.initials: T
authors.lastname: Vervoort
authors.forename: F
authors.initials: F
authors.lastname: Sultan
authors.forename: P
authors.initials: P
authors.lastname: Büscher
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood / Q000134:cerebrospinal fluid; D002555:Cerebrospinal Fluid / Q000469:parasitology; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood / Q000134:cerebrospinal fluid*; D007841:Latex Fixation Tests / Q000295:instrumentation / Q000379:methods / Q000592:standards; D009391:Nephelometry and Turbidimetry; D010274:Parasitology / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014347:Trypanosoma brucei gambiense / Q000276:immunology* / Q000302:isolation & purification; D014353:Trypanosomiasis, African / Q000175:diagnosis*
chemical_list: D000913:Antibodies, Protozoan; D007075:Immunoglobulin M