Browsing by Author "Hobson-Webb, Lisa D"

Now showing 1 - 6 of 6
  • Thumbnail Image
    ItemOpen Access
    B10 Cell Frequencies and Suppressive Capacity in Myasthenia Gravis Are Associated with Disease Severity.
    (Front Neurol, 2017) Yi, John S; Russo, Melissa A; Massey, Janice M; Juel, Vern; Hobson-Webb, Lisa D; Gable, Karissa; Raja, Shruti M; Balderson, Kristina; Weinhold, Kent J; Guptill, Jeffrey T
    Myasthenia gravis (MG) is a T cell-dependent, B cell-mediated disease. The mechanisms for loss of self-tolerance in this disease are not well understood, and recently described regulatory B cell (Breg) subsets have not been thoroughly investigated. B10 cells are a subset of Bregs identified by the production of the immunosuppressive cytokine, interleukin-10 (IL-10). B10 cells are known to strongly inhibit B- and T-cell inflammatory responses in animal models and are implicated in human autoimmunity. In this study, we examined quantitative and qualitative aspects of B10 cells in acetylcholine receptor autoantibody positive MG (AChR-MG) patients and healthy controls. We observed reduced B10 cell frequencies in AChR-MG patients, which inversely correlated with disease severity. Disease severity also affected the function of B10 cells, as B10 cells in the moderate/severe group of MG patients were less effective in suppressing CD4 T-cell proliferation. These results suggest that B10 cell frequencies may be a useful biomarker of disease severity, and therapeutics designed to restore B10 cell frequencies could hold promise as a treatment for this disease through restoration of self-tolerance.
  • Thumbnail Image
    ItemOpen Access
    Oropharyngeal dysphagia may occur in late-onset Pompe disease, implicating bulbar muscle involvement.
    (Neuromuscular disorders : NMD, 2013-04) Hobson-Webb, Lisa D; Jones, Harrison N; Kishnani, Priya S
    Late-onset Pompe disease (presenting after 12 months of age) often presents with limb-girdle and respiratory weakness, but oropharyngeal dysphagia has not been reported previously. A retrospective review of all late-onset Pompe disease patients evaluated in the neuromuscular clinic at Duke University Medical Center from 1999-2010 was performed. Twelve patients were identified and 3 had symptoms of oropharyngeal dysphagia. The medical record was reviewed, including the results of electromyography, videofluroscopic swallow examinations, and motor speech examination including instrumental assessment of lingual force with the Iowa Oral Performance Instrument. Oropharyngeal dysphagia was mild in two cases and severe in one. One of the two patients with mild severity demonstrated oral stage swallow signs; in the other, residual material was observed in the area of the cervical esophagus. In the patient with severe oropharyngeal dysphagia, both the oral and pharyngeal stages of swallowing were affected with penetration and aspiration documented. The degree of swallowing impairment appeared to correlate with overall physical strength and function. Oropharyngeal dysphagia may occur in patients with late-onset Pompe disease, implicating bulbar muscle involvement. Screening for symptoms of dysphagia may help reduce morbidity and mortality, while improving understanding of the late-onset Pompe disease phenotype. Further studies, including examination of the relationship between lingual weakness and oropharyngeal dysphagia, are warranted.
  • Thumbnail Image
    ItemOpen Access
    Respiratory muscle training in late-onset Pompe disease: Results of a sham-controlled clinical trial.
    (Neuromuscular disorders : NMD, 2020-11) Jones, Harrison N; Kuchibhatla, Maragatha; Crisp, Kelly D; Hobson-Webb, Lisa D; Case, Laura; Batten, Milisa T; Marcus, Jill A; Kravitz, Richard M; Kishnani, Priya S
    To address progressive respiratory muscle weakness in late-onset Pompe disease (LOPD), we developed a 12-week respiratory muscle training (RMT) program. In this exploratory, double-blind, randomized control trial, 22 adults with LOPD were randomized to RMT or sham-RMT. The primary outcome was maximum inspiratory pressure (MIP). Secondary and exploratory outcomes included maximum expiratory pressure (MEP), peak cough flow, diaphragm ultrasound, polysomnography, patient-reported outcomes, and measures of gross motor function. MIP increased 7.6 cmH2O (15.9) in the treatment group and 2.7 cmH2O (7.6) in the control group (P = 0.4670). MEP increased 14.0 cmH2O (25.9) in the treatment group and 0.0 cmH2O (12.0) in the control group (P = 0.1854). The only statistically significant differences in secondary/exploratory outcomes were improvements in time to climb 4 steps (P = 0.0346) and daytime sleepiness (P = 0.0160). The magnitude of changes in MIP and MEP in the treatment group were consistent with our pilot findings but did not achieve statistical significance in comparison to controls. Explanations for this include inadequate power and baseline differences in subject characteristics between groups. Additionally, control group subjects appeared to exhibit an active response to sham-RMT and therefore sham-RMT may not be an optimal control condition for RMT in LOPD.
  • Thumbnail Image
    ItemOpen Access
    Small-fiber neuropathy in pompe disease: first reported cases and prospective screening of a clinic cohort.
    (Am J Case Rep, 2015-04-03) Hobson-Webb, Lisa D; Austin, Stephanie L; Jain, Sneha; Case, Laura E; Greene, Karla; Kishnani, Priya S
    BACKGROUND: Prior autopsy reports demonstrate glycogen deposition in Schwann cells of the peripheral nerves in patients with infantile and late-onset Pompe disease (LOPD), but little is known about associated clinical features. CASE REPORT: Here, we report the first confirmed cases of small-fiber neuropathy (SFN) in LOPD and present the results of a first attempt at screening for SFN in this patient population. After confirming small-fiber neuropathy in 2 LOPD patients, 44 consecutive Pompe patients (iOPD=7, LOPD n=37) presenting to the Duke University Glycogen Storage Disease Program between September 2013 and November 2014 were asked to complete the 21-item Small-Fiber Neuropathy Screening List (SFNSL), where a score of ≥11 is considered to be a positive screen. Fifty percent of patients had a positive SFN screen (mean score 11.6, 95% CI 9.0-14.2). A modest correlation between the SFNSL score and current age was seen (r=0.38, p=0.01), along with a correlation with duration of ERT (r=0.31, p=0.0495). Trends toward correlation with forced vital capacity and age at diagnosis were also present. Women had a higher mean SFNSL score (14.2) than men (8.2, p=0.017). CONCLUSIONS: SFN may occur in association with Pompe disease and precede the diagnosis. Further studies are needed to determine its true prevalence and impact.
  • Thumbnail Image
    ItemOpen Access
    The emerging phenotype of late-onset Pompe disease: A systematic literature review.
    (Molecular genetics and metabolism, 2017-03) Chan, Justin; Desai, Ankit K; Kazi, Zoheb B; Corey, Kaitlyn; Austin, Stephanie; Hobson-Webb, Lisa D; Case, Laura E; Jones, Harrison N; Kishnani, Priya S

    Background

    Pompe disease is an autosomal recessive disorder caused by deficiency of the lysosomal glycogen-hydrolyzing enzyme acid α-glucosidase (GAA). The adult-onset form, late-onset Pompe disease (LOPD), has been characterized by glycogen accumulation primarily in skeletal, cardiac, and smooth muscles, causing weakness of the proximal limb girdle and respiratory muscles. However, increased scientific study of LOPD continues to enhance understanding of an evolving phenotype.

    Purpose

    To expand our understanding of the evolving phenotype of LOPD since the approval of enzyme replacement therapy (ERT) with alglucosidase alfa (Myozyme™/Lumizyme™) in 2006.

    Methods

    All articles were included in the review that provided data on the charactertistics of LOPD identified via the PubMed database published since the approval of ERT in 2006. All signs and symptoms of the disease that were reported in the literature were identified and included in the review.

    Results

    We provide a comprehensive review of the evolving phenotype of LOPD. Our findings support and extend the knowledge of the multisystemic nature of the disease.

    Conclusions

    With the advent of ERT and the concurrent increase in the scientific study of LOPD, the condition once primarily conceptualized as a limb-girdle muscle disease with prominent respiratory involvement is increasingly recognized to be a condition that results in signs and symptoms across body systems and structures.
  • Thumbnail Image
    ItemOpen Access
    Tongue weakness and atrophy differentiates late-onset Pompe disease from other forms of acquired/hereditary myopathy.
    (Molecular genetics and metabolism, 2021-07) Jones, Harrison N; Hobson-Webb, Lisa D; Kuchibhatla, Maragatha; Crisp, Kelly D; Whyte-Rayson, Ashley; Batten, Milisa T; Zwelling, Paul J; Kishnani, Priya S
    Late-onset Pompe disease (LOPD) is an inherited autosomal recessive progressive metabolic myopathy that presents in the first year of life to adulthood. Clinical presentation is heterogeneous, differential diagnosis is challenging, and diagnostic delay is common. One challenge to differential diagnosis is the overlap of clinical features with those encountered in other forms of acquired/hereditary myopathy. Tongue weakness and imaging abnormalities are increasingly recognized in LOPD. In order to explore the diagnostic potential of tongue involvement in LOPD, we assessed tongue structure and function in 70 subjects, including 10 with LOPD naive to treatment, 30 with other acquired/hereditary myopathy, and 30 controls with neuropathy. Tongue strength was assessed with both manual and quantitative muscle testing. Ultrasound (US) was used to assess tongue overall appearance, echointensity, and thickness. Differences in tongue strength, qualitative appearance, echointensity, and thickness between LOPD subjects and neuropathic controls were statistically significant. Greater tongue involvement was observed in LOPD subjects compared to those with other acquired/hereditary myopathies, based on statistically significant decreases in quantitative tongue strength and sonographic muscle thickness. These findings provide additional evidence for tongue involvement in LOPD characterized by weakness and sonographic abnormalities suggestive of fibrofatty replacement and atrophy. Findings of quantitative tongue weakness and/or atrophy may aid differentiation of LOPD from other acquired/hereditary myopathies. Additionally, our experiences in this study reveal US to be an effective, efficient imaging modality to allow quantitative assessment of the lingual musculature at the point of care.