IgM quantification in the cerebrospinal fluid of sleeping sickness patients by a latex card agglutination test

Trop Med Int Health. 2002 Aug;7(8):685-92. doi: 10.1046/j.1365-3156.2002.00917.x.

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.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Protozoan / blood
  • Antibodies, Protozoan / cerebrospinal fluid
  • Cerebrospinal Fluid / parasitology
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Immunoglobulin M / blood
  • Immunoglobulin M / cerebrospinal fluid*
  • Latex Fixation Tests / instrumentation
  • Latex Fixation Tests / methods
  • Latex Fixation Tests / standards
  • Nephelometry and Turbidimetry
  • Parasitology / methods
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Trypanosoma brucei gambiense / immunology*
  • Trypanosoma brucei gambiense / isolation & purification
  • Trypanosomiasis, African / diagnosis*

Substances

  • Antibodies, Protozoan
  • Immunoglobulin M