LONG-TERM EFFECT OF INTRAVENOUS IMMUNOGLOBULINS AND ORAL CYCLOPHOSPHAMIDE IN MULTIFOCAL MOTOR NEUROPATHY

Objectives-To report the long term effect of the combined treatment wi th high dose intravenous immunoglobulins (IVIg) and oral cyclophospham ide (CTX) in patients with multifocal motor neuropathy, and to determi ne whether the association of oral CTX in these patients may help to d elay and, possibly, suspend IVIg infusions. Methods-Six patients with multifocal motor neuropathy responding to an initial course of IVIg (0 .4 g/kg/day for five consecutive days) were followed up for 37 to 61 ( mean 47) months. All patients were subsequently treated with periodic IVIg infusions (0.4 g/kg/day for two days at clinical worsening) and o ral CTX (1-3 mg/kg/day). Improvement was assessed using the Rankin dis ability scale, a functional impairment scale for upper and lower limbs , and the MRC rating scale on the 20 most affected muscles. Electrophy siological and antiglycolipid antibody studies were performed before t reatment, then yearly during follow up. Results-All patients improved during treatment and, by the end of follow up or before worsening afte r therapy suspension, the median Rankin (P=0.0335) and upper (P=0.0015 ) and lower Limb (P=0.0301) impairment scores and the mean MRC (P=0.05 61) score were improved. By that time the number of nerves with partia l motor conduction block was reduced (P=0.0197) and antiglycolipid ant ibody titres had decreased in all but one patient. All patients requir ed periodic IVIg infusions to maintain improvement but, after three to seven months of oral CTX, the interval between IVIg infusions could b e progressively prolonged until, in three patients, both treatments co uld be stopped for up to two years before clinical worsening. The main complications, both related to oral CTX, were haemorrhagic cystitis i n two patients and persistent amenorrhea in one patient. Conclusions-I VIg can induce and maintain improvement in multifocal motor neuropathy but does not eradicate the disease. Oral CTX may help to induce a sus tained remission but it is not devoid of side effects and might theref ore be reserved for patients with multifocal motor neuropathy who requ ire frequent IVIg infusions to maintain improvement.