A double-blind, placebo-controlled study of rituximab in patients with stiff person syndrome.

OBJECTIVE: In stiff person syndrome (SPS), an antibody-mediated impaired γ-aminobutyric acidergic (GABAergic) neurotransmission is believed to cause muscle stiffness and spasms. Most patients improve with GABA-enhancing drugs and intravenous immunoglobulin, but some respond poorly and remain disabled. The need for more effective therapy prompted a trial with the anti-CD20 monoclonal antibody rituximab. METHODS: This was a placebo-controlled randomized trial of rituximab (2 biweekly infusions of 1g each). The primary outcome was a change in stiffness scores at 6 months. Secondary outcomes were changes in heightened-sensitivity and quality of life scores. Enrolling 24 patients was calculated to detect 50% change in stiffness scores. RESULTS: Randomization was balanced for age, sex, disease duration, and glutamic acid decarboxylase autoantibody titers. No significant changes were noted at 6 months after treatment in all outcomes. Specifically, no differences were noted in the stiffness index, the primary outcome, or sensitivity scores, the secondary outcome, at 3 or 6 months. Quality of life scores improved significantly (p < 0.01) at 3 months in both groups, but not at 6 months, denoting an early placebo effect. Blinded self-assessment rating of the overall stiffness for individual patients revealed improvement in 4 patients in each group. At 6 months, improvement persisted in 1 patient in the placebo group versus 3 of 4 in the rituximab group, where these meaningful improvements were also captured by video recordings. INTERPRETATION: This is the largest controlled trial conducted in SPS patients and demonstrates no statistically significant difference in the efficacy measures between rituximab and placebo. Rituximab's lack of efficacy could be due to a considerable placebo effect; insensitivity of scales to quantify stiffness, especially in the less severely affected patients; or drug effectiveness in only a small patient subset. Ann Neurol 2017;82:271-277.

Placebo-controlled trial of rituximab in IgM anti-myelin-associated glycoprotein antibody demyelinating neuropathy.

OBJECTIVE: Report a double-blind, placebo-controlled study of rituximab in patients with anti-MAG demyelinating polyneuropathy (A-MAG-DP). METHODS: Twenty-six patients were randomized to four weekly infusions of 375 mg/m(2) rituximab or placebo. Sample size was calculated to detect changes of > or = 1 Inflammatory Neuropathy Course and Treatment (INCAT) leg disability scores at month 8. IgM levels, anti-MAG titers, B cells, antigen-presenting cells, and immunoregulatory T cells were monitored every 2 months. RESULTS: Thirteen A-MAG-DP patients were randomized to rituximab and 13 to placebo. Randomization was balanced for age, electrophysiology, disease duration, disability scores, and baseline B cells. After 8 months, by intention to treat, 4 of 13 rituximab-treated patients improved by > or = 1 INCAT score compared with 0 of 13 patients taking placebo (p = 0.096). Excluding one rituximab-randomized patient who had normal INCAT score at entry, and thus could not improve, the results were significant (p = 0.036). The time to 10m walk was significantly reduced in the rituximab group (p = 0.042) (intention to treat). Clinically, walking improved in 7 of 13 rituximab-treated patients. At month 8, IgM was reduced by 34% and anti-MAG titers by 50%. CD25+CD4+Foxp3+ regulatory cells significantly increased by month 8. The most improved patients were those with high anti-MAG titers and most severe sensory deficits at baseline. INTERPRETATION: Rituximab is the first drug that improves some patients with A-MAG-DP in a controlled study. The benefit may be exerted by reducing the putative pathogenic antibodies or by inducing immunoregulatory T cells. The results warrant confirmation with a larger trial.

Effect of Alemtuzumab (CAMPATH 1-H) in patients with inclusion-body myositis.

Sporadic inclusion-body myositis (sIBM) is the most common disabling, adult-onset, inflammatory myopathy histologically characterized by intense inflammation and vacuolar degeneration. In spite of T cell-mediated cytotoxicity and persistent, clonally expanded and antigen-driven endomysial T cells, the disease is resistant to immunotherapies. Alemtuzumab is a humanized monoclonal antibody that causes an immediate depletion or severe reduction of peripheral blood lymphocytes, lasting at least 6 months. We designed a proof-of-principle study to examine if one series of Alemtuzumab infusions in sIBM patients depletes not only peripheral blood lymphocytes but also endomysial T cells and alters the natural course of the disease. Thirteen sIBM patients with established 12-month natural history data received 0.3 mg/kg/day Alemtuzumab for 4 days. The study was powered to capture > or =10% increase strength 6 months after treatment. The primary end-point was disease stabilization compared to natural history, assessed by bi-monthly Quantitative Muscle Strength Testing and Medical Research Council strength measurements. Lymphocytes and T cell subsets were monitored concurrently in the blood and the repeated muscle biopsies. Alterations in the mRNA expression of inflammatory, stressor and degeneration-associated molecules were examined in the repeated biopsies. During a 12-month observation period, the patients' total strength had declined by a mean of 14.9% based on Quantitative Muscle Strength Testing. Six months after therapy, the overall decline was only 1.9% (P < 0.002), corresponding to a 13% differential gain. Among those patients, four improved by a mean of 10% and six reported improved performance of daily activities. The benefit was more evident by the Medical Research Council scales, which demonstrated a decline in the total scores by 13.8% during the observation period but an improvement by 11.4% (P < 0.001) after 6 months, reaching the level of strength recorded 12 months earlier. Depletion of peripheral blood lymphocytes, including the naive and memory CD8+ cells, was noted 2 weeks after treatment and persisted up to 6 months. The effector CD45RA(+)CD62L(-) cells, however, started to increase 2 months after therapy and peaked by the 4th month. Repeated muscle biopsies showed reduction of CD3 lymphocytes by a mean of 50% (P < 0.008), most prominent in the improved patients, and reduced mRNA expression of stressor molecules Fas, Mip-1a and alphaB-crystallin; the mRNA of desmin, a regeneration-associated molecule, increased. This proof-of-principle study provides insights into the pathogenesis of inclusion-body myositis and concludes that in sIBM one series of Alemtuzumab infusions can slow down disease progression up to 6 months, improve the strength of some patients, and reduce endomysial inflammation and stressor molecules. These encouraging results, the first in sIBM, warrant a future study with repeated infusions

Lower extremity peak force and gait kinematics in individuals with inclusion body myositis.

OBJECTIVE: To determine the relationship between peak isometric muscle force and temporal characteristics of gait in individuals with sporadic inclusion body myositis (s-IBM). METHODS: An observational study of 42 individuals with s-IBM (12 women; mean ± SD age 61.8 ± 7.3 years and mean ± SD disease duration 8.9 ± 4.3 years) was conducted at a federal hospital. Peak isometric force measurements for lower extremity (LE) muscle groups were obtained using quantitative muscle testing. Temporal characteristics of gait during habitual and fast walking conditions were measured using a portable gait analysis system. RESULTS: All observed muscle force values were significantly lower than predicted values (P ≤ 0.001). During habitual walking, the subjects' gait speed and cadence were ≤83% of normative literature values. During fast walking, total gait cycle time was 133% of normal, while gait speed and cadence were 58% and 78% of normative literature values, respectively. Scaled LE peak muscle forces showed significant moderate correlations with temporal gait variables. Weaker subjects had greater limitations in gait speed and cadence compared with stronger subjects (P < 0.05). Peak isometric force of the knee flexors and ankle plantar flexors was significantly correlated with most temporal features of habitual gait. CONCLUSION: Muscle weakness associated with s-IBM disease activity may contribute to diminished gait kinematics. Temporal features of gait were not substantially influenced by knee extensor weakness alone, considering the knee flexors and ankle plantar flexors played a compensatory role in maintaining the walking ability of individuals with s-IBM.

Reliability of the adult myopathy assessment tool in individuals with myositis.

OBJECTIVE: The Adult Myopathy Assessment Tool (AMAT) is a 13-item performance-based battery developed to assess functional status and muscle endurance. The purpose of this study was to determine the intrarater and interrater reliability of the AMAT in adults with myositis. METHODS: Nineteen raters (13 physical therapists and 6 physicians) scored videotaped recordings of patients with myositis performing the AMAT for a total of 114 tests and 1,482 item observations per session. Raters rescored the AMAT test and item observations during a followup session (mean ± SD 19 ± 6 days between scoring sessions). All raters completed a single, self-directed, electronic training module prior to the initial scoring session. RESULTS: Intrarater and interrater reliability correlation coefficients were ≥0.94 for the AMAT functional subscale, endurance subscale, and total score (all P < 0.02 for Ho , ρ ≤0.75). All AMAT items had satisfactory intrarater agreement (kappa statistics with Fleiss-Cohen weights, with values κw = 0.57-1.00). Interrater agreement was acceptable for each AMAT item (κ = 0.56-0.89) except the sit up (κ = 0.16). The standard error of measurement and 95% confidence interval range for the AMAT total scores did not exceed 2 points across all observations (AMAT total score range 0-45). CONCLUSION: The AMAT is a reliable, domain-specific assessment of functional status and muscle endurance for adult subjects with myositis. Results of this study suggest that physicians and physical therapists may reliably score the AMAT following a single training session. The AMAT functional subscale, endurance subscale, and total score exhibit interrater and intrarater reliability suitable for clinical and research use.

Superiority of 6-[18F]-fluorodopamine positron emission tomography versus [131I]-metaiodobenzylguanidine scintigraphy in the localization of metastatic pheochromocytoma.

The purpose of the study was to assess the diagnostic utility of 6-[(18)F]-fluorodopamine ([(18)F]-DA) positron emission tomography scanning (PET) vs. [(131)I]-metaiodobenzylguanidine (MIBG) scintigraphy in patients with metastatic pheochromocytoma (PHEO). We studied 10 men and six women (mean age 38.2 +/- 11.5 yr) referred to our institution for metastatic PHEO; two patients were studied twice within a 2-yr interval. Imaging modalities included computed tomography (CT), magnetic resonance imaging (MRI), [(131)I]-MIBG scintigraphy, and [(18)F]-DA PET. Fifteen of 16 patients had positive findings on CT and/or MRI consistent with the presence of pheochromocytoma. [(18)F]-DA PET was positive in all patients, but seven patients had negative [(131)I]-MIBG scans. Thirty-eight foci of uptake were shown by both [(18)F]-DA PET and [(131)I]-MIBG scintigraphy, 90 only by [(18)F]-DA PET, and 10 only by [(131)I]-MIBG; most lesions were also visible on CT/MRI. In this initial series of patients with metastatic pheochromocytoma, [(18)F]-DA PET localized PHEO in all patients and showed a large number of foci that were not imaged with [(131)I]-MIBG scintigraphy. Thus, [(18)F]-DA PET was found to be a superior imaging method in patients with metastatic PHEO, in which correct detection of disease extension often determines the most appropriate therapeutic plan and future follow-up.

Validity of the single limb heel raise test to predict lower extremity disablement in patients with sporadic inclusion body myositis.

PURPOSE: To determine the validity of the single limb heel raise (SLHR) test as a potential screening tool to detect lower extremity disability in patients with sporadic inclusion body myositis (sIBM). METHODS: We compared gait speed and fall history between subjects with sIBM who either could complete one SLHR (SLHR group) or could not complete one SLHR. Discriminative validity was established by comparing between group differences in functional measures based on group assignment. Receiver operating characteristics curve analysis was used to determine the predictive validity of completing one repetition on the SLHR test. Spearman correlations were used to determine the association between gait kinematics and number of repetitions achieved on the SLHR test. RESULTS: Forty-three subjects (13 females) were studied. The SLHR group (n = 21) showed significantly greater gait speed (p < 0.001) and decreased gait aid use (p < 0.05) compared to the no SLHR group (n = 22). SLHR cut scores of 1, 20, and 22 repetitions maximized positive likelihood ratios (+LR) for the ability to walk at 54.9 (+LR. 2.2), 63.2 (+LR. 9.5), and 73.1 m/min (+LR. 5.0), respectively. CONCLUSION: The SLHR test demonstrates adequate discriminative and predictive validity as a screening tool for lower extremity disablement in patients with sIBM. Implications for Rehabilitation The SLHR test has adequate reliability and validity to screen for the presence of lower extremity disablement in patients with sIBM. Results of this rapid field test may be used to guide the need for rehabilitation services to mitigate the effects of slow gait speeds in patients with sIBM.

Are repeated single-limb heel raises and manual muscle testing associated with peak plantar-flexor force in people with inclusion body myositis?

BACKGROUND: Repeated heel raises have been proposed as a method of ankle plantar-flexor strength testing that circumvents the limitations of manual muscle testing (MMT). OBJECTIVE: The study objective was to examine the relationships among ankle plantar-flexion isometric maximum voluntary contraction (MVC), repeated single-limb heel raises (SLHRs), and MMT in people with myositis. DESIGN: This was a cross-sectional study with a between-group design. The ability to complete 1 SLHR determined group assignment (SLHR group, n=24; no-SLHR group, n=19). METHODS: Forty-three participants with myositis (13 women; median age=64.9 years) participated. Outcome measures included MVC, predicted MVC, Kendall MMT, and Daniels-Worthingham MMT. RESULTS: The Kendall MMT was unable to detect significant ankle plantar-flexor weakness established by quantitative methods and was unable to discriminate between participants who could and those who could not perform the SLHR task. Ankle plantar-flexion MVC was not associated with the number of heel-raise repetitions in the SLHR group (pseudo R(2)=.13). No significant relationship was observed between MVC values and MMT grades in the SLHR and no-SLHR groups. However, a moderate relationship between MVC values and MMT grades was evident in a combined-group analysis (ρ=.50-.67). LIMITATIONS: The lower half of both MMT grading scales was not represented in the study despite the profound weakness of the participants. CONCLUSIONS: Both Kendall MMT and Daniels-Worthingham MMT had limited utility in the assessment of ankle plantar-flexor strength. Repeated SLHRs should not be used as a proxy measure of ankle plantar-flexion MVC in people with myositis.

Gender-related differences in the clinical presentation of malignant and benign pheochromocytoma.

Signs and symptoms associated with pheochromocytomas are predominantly caused by catecholamine excess, but tend to be highly variable and non-specific. In this study, we evaluated 23 male and 35 female pheochromocytoma patients for symptoms and signs of pheochromocytoma with special regard to gender-related differences in presentation. Total symptom score comparison between genders showed significant differences (12.0 vs. 7.8, P-value 0.0001). Female patients reported significantly more headache (80% vs. 52%), dizziness (83% vs. 39%), anxiety (85% vs. 50%), tremor (64% vs. 33%), weight change (88% vs. 43%), numbness (57% vs. 24%), and changes in energy level (89% vs. 64%). Females and males displayed comparable biochemical phenotypes (60% and 65% noradrenergic phenotype, respectively). Use of alpha- and/or beta-blockade between males and females did not differ significantly. Subgroup analyses and multiple regression analysis revealed gender differences to be irrespective of benign or malignant disease, use of adrenoceptor-blockade, age and biochemical phenotype. We conclude female patients have significantly more self-reported pheochromocytoma signs and symptoms than male patients irrespective of biochemical phenotype and tumor presentation which may be related to distinct catecholamine receptor sensitivity. Clinicians should be aware of these complaints in female pheochromocytoma patients and offer adequate treatment if indicated.