Motor Unit Number Estimation (MUNE), a technique allowing to estimate the number of functioning Motor Units (MU) in single muscles, was used to score the disease's severity and progression rate in a group of 58 patients with Amyotrophic Lateral Sclerosis (ALS). All patients underwent MUNE in the abductor digiti minimi (ADM) muscle during the diagnostic work-up (T0), after three (T1) and six (T2) months. A significant loss [p < .001] of MU and a decrease [p < .001] of the maximal M wave area at T0 was found, whereas mean step area was increased [p < .001]. During the follow-up (T1 and T2), MU loss continued, maximal M wave decreased, and mean step area increased significantly. The results confirm that MUNE is a suitable tool to quantify the pathological changes in MU in patients with ALS.

No abstract

Objective: Interferon-b (IFN-b) is a widely used therapy for multiple sclerosis (MS), a demyelinating disease of the central nervous system. This study has evaluated the effect on thyroid function and autoimmunity of a 1-year treatment with IFN-b1b in patients with MS. Patients: We studied 31 patients (age 34 Ϯ 7 years, 21 women) with relapsing-remitting MS during IFN-b1b treatment of 1 year duration. Systematic thyroid assessment and measurements of serum interleukin-6 (IL-6) levels were performed at baseline and every 3 months during treatment.Results: Sixteen percent of the patients had autoimmune thyroiditis before IFN-b1b, all positive for anti-peroxidase antibodies. The overall incidence of thyroid dysfunction was 33% over 1 year (10% hyperthyroidism, 23% hypothyroidism). Thyroid autoimmunity developed in 5/26 patients (19%), in one case without dysfunction. In addition to autoantibody positivity at baseline, female gender and the presence of an ultrasound thyroid pattern suggestive of thyroiditis were identified by multiple logistic regression as additional risk predictors for the development of thyroid dysfunction. During IFN-b1b treatment, serum IL-6 levels rose in a consistent biphasic pattern; there was, however, no difference between patients with or without incident thyroid abnormalities. Conclusions: We conclude that IFN-b1b therapy can induce multiple alterations in thyroid function, some of which are unrelated to thyroid autoimmunity. IL-6 measurement is not useful to identify patients prone to develop thyroid abnormalities. Though thyroid dysfunction is generally subclinical and often transient, systematic thyroid assessment should be performed during IFN-b1b treatment.

The risk of thyroid disease seems related to IFN beta-1b treatment during the first year only, particularly in patients with preexisting thyroiditis. Furthermore, incident thyroid dysfunction is generally transient and mild in degree. Indeed, we recommend a routine systematic thyroid assessment only in patients with baseline thyroiditis. During the first year of therapy, serum thyroid-stimulating hormone measurement should suffice as first line test; a systematic thyroid assessment is only useful for those patients with incidental and persistent dysfunction. Further studies with many patients will be necessary to confirm our suggestions as broad clinical guidelines.

Multiple sclerosis (MS) represents a T-cell-mediated autoimmune demyelinating disease of the central nervous system associated with altered immunoregulation. Interleukin (IL)-6 is a cytokine that has several effects on the neuroimmune system. Specific IL-6 receptors have been found in human lymphocytes and neuroglial cells. The aim of the present study was to assay IL-6 binding on peripheral blood T lymphocytes in MS patients. We found that T cells from MS patients had significantly more IL-6 receptors [Bmax: 279 +/- 7 vs. 246 +/- 8 (mean +/- SEM) receptors/cell, in patients and controls, respectively], whereas Kd values were similar to those of healthy subjects [26.8 +/- 0.7 vs. 25.4 +/- 0.6 (mean +/- SEM) pM, in patients and controls, respectively]. Significant (P < 0.05) differences in IL-6 binding values were observed between stable patients and those relapsing (272 +/- 9 vs. 300 +/- 12 (mean +/- SEM) receptors/cell, respectively). We found significantly (P < 0. 001) higher amounts of IL-6 receptors on CD4+ T cells from MS patients than on CD4+ lymphocytes from controls (434 +/- 11 vs. 363 +/- 9 (mean +/- SEM) receptors/cell, respectively); CD8+ T cells showed very few IL-6 receptors in both patients and controls. These data are discussed in terms of MS immune pathogenesis and pathophysiology, because T-cell activation seems to be linked to increased IL-6 binding. The upregulated IL-6 system might be involved in antibody-mediated demyelinating pathways, because IL-6 is well known to enhance humoral immune response.