Pharmacokinetics of intravenous immunoglobulin and outcome in Guillain-Barré syndrome.
OBJECTIVE
Intravenous immunoglobulin (IVIg) is the first choice treatment for Guillain-Barré syndrome (GBS). All patients initially receive the same arbitrary dose of 2g per kg body weight. Not all patients, however, show a good recovery after this standard dose. IVIg clearance may depend on disease severity and vary between individuals, implying that this dose is suboptimal for some patients. In this study, we determined whether the pharmacokinetics of IVIg is related to outcome in GBS.


METHODS
We included 174 GBS patients who had previously participated in 2 randomized clinical trials. At entry, all patients were unable to walk unaided and received a standard dose of IVIg. Total IgG levels in serum samples obtained immediately before and 2 weeks after the start of IVIg administration were determined by turbidimetry and related to clinical outcome at 6 months.


RESULTS
The increase in serum IgG (DeltaIgG) 2 weeks after IVIg treatment varied considerably between patients (mean, 7.8g/L; standard deviation, 5.6g/L). Patients with a low DeltaIgG recovered significantly more slowly, and fewer reached the ability to walk unaided at 6 months (log-rank p < 0.001). In multivariate analysis adjusted for other known prognostic factors, a low DeltaIgG was independently associated with poor outcome (p = 0.022).


CONCLUSIONS
After a standard dose of IVIg treatment, GBS patients show a large variation in pharmacokinetics, which is related to clinical outcome. This may indicate that patients with a small increase in serum IgG level may benefit from a higher dosage or second course of IVIg.
Kuitwaard
Krista
K
Department of Neurology, Erasmus Medical Center, Rotterdam, The Netherlands. k.kuitwaard@erasmusmc.nl
de Gelder
Jenny
J
Tio-Gillen
Anne P
AP
Hop
Wim C J
WC
van Gelder
Teun
T
van Toorenenbergen
Albert W
AW
van Doorn
Pieter A
PA
Jacobs
Bart C
BC
D000328:Adult; D000368:Aged; D005260:Female; D020275:Guillain-Barre Syndrome / Q000097:blood* / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D016756:Immunoglobulins, Intravenous / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D008297:Male; D008875:Middle Aged; D020127:Recovery of Function / Q000502:physiology; D016896:Treatment Outcome
D007074:Immunoglobulin G; D016756:Immunoglobulins, Intravenous