Seven adult patients received human immune globulin intravenously as i
nitial therapy for Guillain-Barre syndrome. Although all patients init
ially stabilized or improved, five patients deteriorated 1 to 16 days
after completion of treatment. In all five patients, clinical worsenin
g included loss of at least one functional grade together with a decre
ased forced vital capacity. We subsequently treated each patient with
a course of plasma exchange, which led to varying degrees of clinical
improvement in four. In contrast to previously reported relapse rates
for Guillain-Barre syndrome, our experience suggests that clinically s
ignificant relapses may occur in patients more often following human i
mmune globulin therapy than after either plasma exchange or no therapy
.