In reply
We thank Pellkofer et al for their intriguing letter describing the fascinating case of a patient with SLE and concomitant NMO who had 31 recurrent flares of opticospinal disease. Similar to our case,1 such recurrent opticospinal flares occurred despite treatment with rituximab and suggest that, in such intractable cases, cotreatment with an additional immunosuppressive agent may be necessary. Their article adds to our recent findings that, especially in patients with systemic rheumatic syndromes such as SLE, recurrent attacks of myelitis frequently occur despite potent immunosuppressive therapy. We recently described 22 patients with SLE and myelitis, representing the largest cohort of such patients ever described.2 In our cohort, 11 patients presented with an initial clinical pattern that we have termed white-matter myelitis, characterized by early examination findings of spasticity and hyperreflexia. Nine of these 11 patients satisfied proposed diagnostic criteria for the NMO spectrum of syndromes.3 In these 11 patients, the number of recurrent attacks ranged from 2 to 12. This subset of patients was not only distinguished by the NMO-IgG autoantibody but by seropositivity for anti-Ro/SS-A autoantibody as well as the lupus anticoagulant/antiphospholipid autoantibody. In SLE patients with NMO, the immunologic derangements that are relevant to SLE—and that may not be seen in patients with idiopathic NMO—may modulate the response to rituximab. Complement-mediated lysis of pathogenic B cells may be impaired in patients with SLE, in whom SLE activity may be associated with hypocomplementemia.4 Additionally, a subset of patients with SLE may be deficient in the FcRIIIa allele, which may be important in antibody-mediated cytotoxicity of pathogenic B cells.5