Gangliosides and the Guillain-Barre syndrome No causal link

EDITOR, - Gianluca Landi and colleagues report that 25 cases of the Guillain-Barre syndrome after treatment with gangliosides were seen over four and a half years in Italy, a yearly average of 5.6 cases.1 Their conclusion that these cases represent an excess incidence is incorrect. Their data estimate a yearly exposed population of roughly 2500 000 (4.2% of the Italian population). The 5.6 cases represent a yearly incidence of 0.2/100 000. Eleven of their patients were over 60. The incidence of the Guillain-Barre syndrome is known to be higher in older age groups: an incidence of 3.2/100 000 a year has been reported in people over 60.2

We believe that it is inappropriate to compare the incidence of the Guillain-Barre syndrome in the normal population with that in patients selected for treatment with gangliosides - that is, patients with neuropathy - as the frequency of the syndrome seems to be increased in these patients. This is exemplified by surveys of referrals for generically defined neuropathy^3,4: on accurate examination 11-12% of the cases were diagnosed as cases of the Guillain-Barre syndrome. The syndrome may therefore be diagnosed in over 10% of patients with neuropathy (especially elderly patients), who potentially qualify for ganglioside treatment.

The authors have not exluded the possibility that gangliosides were prescribed for initial signs of …