Raffaella Fazio

Similar low frequency of anti-MOG IgG and IgM in MS patients and healthy subjects.

The authors used a liquid-phase radiobinding assay to measure serum anti-myelin oligodendrocyte protein (MOG) immunoglobulin (Ig) G in 87 patients with multiple sclerosis (MS), in 12 patients with encephalomyelitis, and in 47 healthy subjects. Anti-MOG IgM was determined in samples obtained at onset from 40 of 87 patients with MS and in control subjects. The frequency of positive samples with low titers of anti-MOG IgG (≤5.7%) and IgM (≤8.3%) was similar in all the groups and subgroups. Binding competition experiments showed that these antibodies had low affinity. Anti-MOG antibodies are not disease specific.

Phenotypic clustering of lamin A/C mutations in neuromuscular patients

Background: Mutations in the LMNA gene, encoding human lamin A/C, have been associated with an increasing number of disorders often involving skeletal and cardiac muscle, but no clear genotype/phenotype correlation could be established to date. Methods: We analyzed the LMNA gene in a large cohort of patients mainly affected by neuromuscular or cardiac disease and clustered mutated patients in two groups to unravel possible correlations. Results: We identified 28 variants, 9 of which reported for the first time. The two groups of patients were characterized by clinical and genetic differences: 1) patients with childhood onset displayed skeletal muscle involvement with predominant scapuloperoneal and facial weakness associated with missense mutations; 2) patients with adult onset mainly showed cardiac disorders or myopathy with limb girdle distribution, often associated with frameshift mutations presumably leading to a truncated protein. Conclusions: Our findings, supported by meta-analysis of previous literature, suggest the presence of two different pathogenetic mechanisms: late onset phenotypes may arise through loss of function secondary to haploinsufficiency, while dominant negative or toxic gain of function mechanisms may explain the severity of early phenotypes. This model of patient stratification may help patient management and facilitate future studies aimed at deciphering lamin A/C pathogenesis.

Antiacquaporin 4 antibodies detection by different techniques in neuromyelitis optica patients

Background: Antibodies against aquaporin-4 (AQP4), a water channel particularly expressed on perivascular astrocytic podocytes, are proposed as a marker for the diagnosis of neuromyelitis optica (NMO). However, a consensus on seroprevalence and optimal detection method has not yet been reached. Objectives: To investigate the performance of different assays to detect anti-AQP4 antibodies. Methods: We set up five different assays. Two of them were capable to detect perivascular IgG reactivity on brain tissue by immunofluorescence (NMO-IgG). Other three assays have been set to detect anti-AQP4 antibodies: immunofluorescence and flow cytometry on AQP4-expressing cells, and a radioimmunoprecipitation assay. We assessed sensitivity and specificity of these assays by interrogating sera of 33 NMO patients, 13 patients at high risk to develop NMO (hrNMO), 6 patients affected by acute partial transverse myelitis (APTM), 20 patients with multiple sclerosis (MS), and 67 age- and sex-matched healthy controls. Results: We found that the presence of serum NMO-IgG and anti-AQP4 reactivity is almost exclusively restricted to patients with NMO and hrNMO. Seroprevalence and sensitivity ranged from 30 to 47%, depending on the assay. Specificity ranged from 95 to 100%. Comparing results obtained in the five assays, we noticed lack of concordance in some samples. Conclusions: Detection of NMO-IgG or anti-AQP4 antibodies may represent a valuable tool to assist neurologists in the differential diagnosis between patients with NMO, hrNMO, APTM, or MS. The current lack of a gold standard to detect anti-AQP4 antibodies implies the necessity to standardize the detection of these antibodies.

Rituximab in patients with chronic inflammatory demyelinating polyradiculoneuropathy: a report of 13 cases and review of the literature

Background A few case reports have shown controversial results of rituximab efficacy in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Objective To analyse the efficacy of rituximab in a large CIDP cohort. Methods A retrospective, observational and multicentre study on the use of rituximab in CIDP. 13 Italian CIDP patients were treated with rituximab after the partial or complete lack of efficacy of conventional therapies. Eight patients had co-occurring haematological diseases. Patients who improved by at least two points in standard clinical scales, or who reduced or discontinued the pre-rituximab therapies, were considered as responders. Results Nine patients (seven with haematological diseases) responded to rituximab: six of them, who were non-responders to conventional therapies, improved clinically, and the other three maintained the improvement that they usually achieved with intravenous immunoglobulin or plasma exchange. Significantly associated with shorter disease duration, rituximab responses started after a median period of 2.0 months (range, 1–6) and lasted for a median period of 1 year (range, 1–5). Conclusions Rituximab seems to be a promising therapeutic choice when it targets both CIDP and co-occurring haematological diseases. Timely post-onset administration of rituximab seems to be associated with better responses.

A nationwide retrospective analysis on the effect of immune therapies in patients with chronic inflammatory demyelinating polyradiculoneuropathy

Background and purpose:  The guidelines for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) therapy suggest to use immunoglobulins (IVIg) and steroid as first‐line therapies. Patients who do not respond to one of the two drugs should be switched to the other drug. We collected therapeutic outcome data in patients followed at 11 centres in order to document the clinical practice in Italy.

Polyneuropathy in hypothyroidism: clinical, electrophysiological and morphological findings in four cases.

Clinical, neurophysiological and morphological studies of four patients with polyneuropathy and secondary hypothyroidism are reported. Neurophysiological studies revealed signs of muscle denervation and reduction of conduction velocity in all the patients. Sural nerve biopsies showed axonal degeneration in all cases but one. All the patients were treated with replacement therapy and clinical symptomatology and neurophysiological parameters improved in all patients.

A smooth transition protocol for patients with multifocal motor neuropathy going from intravenous to subcutaneous immunoglobulin therapy: An open-label proof-of-concept study

Intravenous immunoglobulin (IVIG) is the first‐line therapy for multifocal motor neuropathy (MMN). This open‐label multi‐centre study (NCT00701662) assessed the efficacy, safety, and convenience of subcutaneous immunoglobulin (SCIG) in patients with MMN over 6 months, as an alternative to IVIG. Eight MMN patients (42–66 years), on stable IVIG dosing, received weekly SCIG at doses equivalent to previous IVIG using a “smooth transition protocol”. Primary efficacy endpoint was the change from baseline to week 24 in muscle strength. Disability, motor function, and health‐related quality of life (HRQL) endpoints were also assessed. One patient deteriorated despite dose increase and was withdrawn. Muscle strength, disability, motor function, and health status were unchanged in all seven study completers who rated home treatment as extremely good. Four experienced 18 adverse events, of which only two were moderate. This study suggests that MMN patients with stable clinical course on regular IVIG can be switched to SCIG at the same monthly dose without deterioration and with a sustained overall improvement in HRQL.

Immunosuppressive treatment in refractory chronic inflammatory demyelinating polyradiculoneuropathy. A nationwide retrospective analysis

Background and purpose:  There are other options open to patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) who are non‐responders to conventional treatment, including immunosuppressive and immunomodulatory agents (IA). The aim of this study was to assess whether the use of IA is able to increase the number of responders.

Clinical and neurophysiological assessment of immunoglobulin therapy in five patients with multifocal motor neuropathy.

High dose intravenous immunoglobulin (IVIg) is an effective treatment for demyelinating neuropathies. IVIg was given to five patients with multifocal motor neuropathy, a motor neuropathy showing a clinical syndrome of asymmetrical weakness and amyotrophy, electrophysiological evidence of motor conduction block and, in many cases, high titres of serum anti-GM1 antibodies. Muscle strength was evaluated by a conventional score before and after each IVIg course. In all patients there was relevant improvement on muscle strength after each immunoglobulin course, but in most cases the clinical benefits partially declined after three to eight weeks. At the eight month follow up, however, the pretreatment examination showed a significant improvement compared with the initial evaluation. The effects of each IVIg course were still present after a number of courses. Electrophysiological study revealed a decrease in conduction block in one or more nerves in all patients. However, conduction block was unchanged or increased in other sites. IVIg treatment did not affect anti-GM1 antibody titres.

Docetaxel neuropathy : a distal axonopathy

Abstract Docetaxel has been implicated as a causative agent in peripheral neuropathy, but pathological changes in peripheral nerve have not been described. During docetaxel treatment a 54-year-old man developed a sensorimotor polyneuropathy when the overall docetaxel dosage was 540 mg/m2. Neurophysiological investigation revealed a sensorimotor axonal neuropathy. Fascicular sural nerve biopsy showed an axonal neuropathy with a preferentially loss of large myelinated fibers. There was evidence of considerable fiber regeneration. Sensory and motor symptoms progressively improved after docetaxel withdrawal.