Quality assurance for cerebrospinal fluid protein analysis: international consensus by an Internet-based group discussion.
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.
Reiber
Hansotto
H
Neurochemisches Labor, Universität Göttingen, Göttingen, Germany. hreiber@med.uni-goettingen.de
Thompson
Edward J
EJ
Grimsley
Guy
G
Bernardi
Gaetano
G
Adam
Pavel
P
Monteiro de Almeida
Sergio
S
Fredman
Pam
P
Keir
Geoffrey
G
Lammers
Manfred
M
Liblau
Roland
R
Menna-Barreto
Marcio
M
Sá
Maria José
MJ
Seres
Erika
E
Sindic
Christian J M
CJ
Teelken
Albert
A
Trendelenburg
Christian
C
Trojano
María
M
van Antwerpen
Marie-Paule
MP
Verbeek
Marcel M
MM
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
D000418:Albumins; D002556:Cerebrospinal Fluid Proteins; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M