In this study, blood cell counts and serum C3, C4, and CH50 values at baseline and after more than 6-month drug use were measured to elucidate changes in blood cells and complements during relapse prevention therapies for aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4+ NMOSD). A total of 70 patients with AQP4+ NMOSD (87% female, median age 56 years) were enrolled. They were divided into the following treatment groups: glucocorticoids and/or immunosuppressants (GC/IS, n = 22), inebilizumab/rituximab (anti-CD19/20, n = 13), satralizumab (anti-IL-6R, n = 22), and eculizumab/ravulizumab (anti-C5, n = 13). At baseline, the blood counts and complement levels did not differ among the groups. At follow-up, the neutrophil and platelet counts in the anti-IL-6R group decreased from those at baseline (p < 0.0001 and p < 0.001, respectively). Compared with the GC/IS, anti-CD19/20, and anti-C5 groups, the anti-IL-6R group had lower levels of C3 (p < 0.0001, p < 0.01, and p < 0.05, respectively) and C4 (p < 0.0001, p < 0.01, p < 0.001, respectively). Furthermore, the anti-C5 group had significantly lower CH50 levels than the GC/IS, anti-CD19/20, and anti-IL-6R groups (p < 0.0001, p < 0.0001, p < 0.05, respectively). In addition, the anti-IL-6R group had lower CH50 levels than the GC/IS and anti-CD19/20 groups (p < 0.001 and p < 0.05, respectively). The present study demonstrated that anti-IL-6R therapy broadly and mildly suppressed the complement system and decreased the neutrophil and platelet counts. It also showed that anti-C5 therapy strongly suppressed total complement activity but did not affect the C3 and C4 levels or blood counts. These findings may have implications for the mode of action of the drugs and the risk of adverse drug reactions, including infections.

A 76-year-old man was admitted to our hospital with progressive dysphagia. His physical and neurological examination results were normal, except for dysphagia. Videofluoroscopy of swallowing demonstrated a cricopharyngeal bar, a highly specific finding for inclusion body myositis (IBM). A cricopharyngeal muscle specimen was obtained during cricopharyngeal myotomy to improve his symptoms. Muscle histopathology successfully led to the diagnosis of IBM. Dysphagia can occasionally precede limb weakness in IBM, and an early histopathological diagnosis using limb muscles is challenging. In such cases, a histopathological evaluation via myotomy may be useful for making an early diagnosis and facilitating appropriate treatment.

Optic perineuritis (OPN) is an uncommon form of the orbital inflammatory disease targeting the optic nerve sheath, which is distinct from optic neuritis. It causes reduced visual acuity and ocular pain and is linked to infection or autoimmunity, including myelin oligodendrocyte glycoprotein-associated disease, but 30-50% are idiopathic. We report three cases of OPN with ocular scleritis and hypertrophic pachymeningitis occurring together or sequentially; in one, pachymeningitis extended from the optic sheath, in two, it was separate. Case 1: 54-year-old man with a history of ocular scleritis developed left ocular pain, diplopia, and visual loss. MRI showed left optic sheath hyperintensity and dural enhancement. Serology and CSF were unremarkable. Intravenous methylprednisolone (IVMP) followed by prednisolone (PSL) improved visual accuracy to 20/13, with no relapse at 10 months on tapering PSL. Case 2: 76-year-old man developed ocular scleritis, OPN, and hypertrophic pachymeningitis presenting as orbital apex syndrome. Blood examination showed pancytopenia. After the treatment of concomitant pneumonia, IVMP partially improved symptoms. Later, he was also diagnosed as myelodysplastic syndrome. He did not relapse without further immunotherapy. Case 3: 63-year-old woman with previous history of ocular scleritis developed acute right visual loss. MRI showed optic sheath and connected dural enhancement. IVMP followed by PSL treatment improved vision from no light perception to 20/125, without relapse at 7 months. These cases suggested possible shared connective-tissue autoimmunity, and warrant attention to the overlap of the three diseases.