title: Quality assurance for cerebrospinal fluid protein analysis: international consensus by an Internet-based group discussion.
abstract: A group of neurologists and clinical neurochemists representing twelve countries worked towards a consensus on laboratory techniques to improve the quality of analysis and interpretation of cerebrospinal fluid (CSF) proteins. Consensus was approached via a virtual Lotus Notes-based TeamRoom. This new approach respecting multicultural differences, common views, and minority opinions, is available in http://www.teamspace.net/ CSF, presenting the implicit, complementary version of this explicit, printed consensus. Three key recommendations were made: CSF and (appropriately diluted) serum samples should be analyzed together in one analytical run, i.e., with reference to the same calibration curve. Results are evaluated as CSF/serum quotients, taking into account the non-linear, hyperbolic relation between immunoglobulin (Ig)- and albumin-quotients rather than using the linear IgG index or IgG synthesis rate. Controls should include materials with values within the reference ranges (IgM: 0.5-1.5 mg/l; IgA: 1-3 mg/l; IgG: 10-30 mg/l and albumin: 100-300 mg/l). The physiological, methodological and clinical significance of CSF/serum quotients is reviewed. We confirmed the previous consensus on oligoclonal IgG, in particular the usefulness of the five typical interpretation patterns. The group compared current external and internal quality assurance schemes and encouraged all members to maintain national or local traditions. Values for acceptable imprecision in the CSF quality assurance are proposed.
authors.affiliation: Neurochemisches Labor, Universität Göttingen, Göttingen, Germany. hreiber@med.uni-goettingen.de
authors.forename: Hansotto
authors.initials: H
authors.lastname: Reiber
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Thompson
authors.forename: Guy
authors.initials: G
authors.lastname: Grimsley
authors.forename: Gaetano
authors.initials: G
authors.lastname: Bernardi
authors.forename: Pavel
authors.initials: P
authors.lastname: Adam
authors.forename: Sergio
authors.initials: S
authors.lastname: Monteiro de Almeida
authors.forename: Pam
authors.initials: P
authors.lastname: Fredman
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Keir
authors.forename: Manfred
authors.initials: M
authors.lastname: Lammers
authors.forename: Roland
authors.initials: R
authors.lastname: Liblau
authors.forename: Marcio
authors.initials: M
authors.lastname: Menna-Barreto
authors.forename: Maria José
authors.initials: MJ
authors.lastname: Sá
authors.forename: Erika
authors.initials: E
authors.lastname: Seres
authors.forename: Christian J M
authors.initials: CJ
authors.lastname: Sindic
authors.forename: Albert
authors.initials: A
authors.lastname: Teelken
authors.forename: Christian
authors.initials: C
authors.lastname: Trendelenburg
authors.forename: María
authors.initials: M
authors.lastname: Trojano
authors.forename: Marie-Paule
authors.initials: MP
authors.lastname: van Antwerpen
authors.forename: Marcel M
authors.initials: MM
authors.lastname: Verbeek
mesh_terms: D000418:Albumins / Q000134:cerebrospinal fluid*; D002556:Cerebrospinal Fluid Proteins / Q000032:analysis*; D002624:Chemistry, Clinical / Q000592:standards / Q000706:statistics & numerical data; D019411:Clinical Laboratory Techniques; D003195:Computer Communication Networks / Q000458:organization & administration; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood / Q000134:cerebrospinal fluid*; D007074:Immunoglobulin G / Q000097:blood / Q000134:cerebrospinal fluid*; D007075:Immunoglobulin M / Q000097:blood / Q000134:cerebrospinal fluid*; D007525:Isoelectric Focusing; D011785:Quality Assurance, Health Care; D011786:Quality Control
chemical_list: D000418:Albumins; D002556:Cerebrospinal Fluid Proteins; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M