Kelly Gwathmey

Neurologic indications for therapeutic plasma exchange: 2013 update: Neurologic Indications for Therapeutic Plasma Exchange

Neurologists commonly use therapeutic plasma exchange (TPE) to treat a number of conditions. This concise review considers the most common neurologic indications for TPE. It focuses on Guillain–Barré syndrome and myasthenia gravis and also the role of TPE in chronic inflammatory demyelinating polyneuropathy, Lambert–Eaton syndrome, multiple sclerosis, neuromyelitis optica, paraproteinemic polyneuropathy, Sydenhams chorea, and natalizumab‐associated progressive multifocal leukoencephalopathy. As with any treatment, the proven efficacy, cost, side effects, and availability must be considered before initiation of therapy. J. Clin. Apheresis 29:211–219, 2014.

Sensory neuronopathies: Sensory Neuronopathies

The sensory neuronopathies (or ganglionopathies) are a small subcategory of neuropathies characterized by primary degeneration of the dorsal root ganglia and trigeminal ganglion sensory neurons, resulting in a distinctive clinical presentation. Patients typically have subacute onset of asymmetric, non–length‐dependent sensory impairment and early ataxia. The etiologies of acquired sensory neuronopathies are rather limited. Early identification is imperative, as they may herald an underlying malignancy or an autoimmune condition such as Sjögren syndrome. This review addresses the various causes of acquired sensory neuronopathies, the recommended diagnostic approach, and treatment options. Finally, I will briefly discuss a select few hereditary and degenerative sensory neuronopathies, which, in contrast to the acquired disorders, are slowly progressive and are usually associated with additional neurological symptoms. Muscle Nerve 53: 8–19, 2016

International clinimetric evaluation of the MG-QOL15, resulting in slight revision and subsequent validation of the MG-QOL15r.

Introduction: The MG‐QOL15 is a validated, health‐related quality of life (HRQOL) measure for myasthenia gravis (MG). Widespread use of the scale gave us the opportunity to further analyze its clinimetric properties. Methods: We first performed Rasch analysis on >1,300 15‐item Myasthenia Gravis Quality of Life scale (MG‐QOL15) completed surveys. Results were discussed during a conference call with specialists and biostatisticians. We decided to revise 3 items and prospectively evaluate the revised scale (MG‐QOL15r) using either 3, 4, or 5 responses. Rasch analysis was then performed on >1,300 MG‐QOL15r scales. Results: The MGQOL15r performed slightly better than the MG‐QOL15. The 3‐response option MG‐QOL15r demonstrated better clinimetric properties than the 4‐ or 5‐option scales. Relative distributions of item and person location estimates showed good coverage of disease severity. Conclusions: The MG‐QOL15r is now the preferred HRQOL instrument for MG because of improved clinimetrics and ease of use. This revision does not negate previous studies or interpretations of results using the MG‐QOL15. Muscle Nerve 54: 1015–1022, 2016

Disease course and therapeutic approach in dermatomyositis: A four-center retrospective study of 100 patients.

Dermatomyositis is a life-altering inflammatory disorder of skin and muscle. Details regarding the natural course of this disorder, the effects of specific therapies on its progression, and the optimal therapeutic dosage and duration of prednisone are limited. We performed a retrospective medical record review of dermatomyositis patients at four medical centers. All patients were over the age of 21 and had a clinical diagnosis of dermatomyositis with pathological confirmation. We reviewed average muscle strength, corticosteroid use, creatine kinase levels, and supplemental immunosuppressant use during the 36-month period following each patients initial assessment. One hundred patients participated with an average age of 50.1 years. Average muscle strength improved and prednisone requirements lessened six months after initial assessment. There was no difference in the mean change in muscle strength or cumulative corticosteroid use over 36 months among those initially treated with methotrexate, mycophenolate mofetil, pulse IVIG, or azathioprine. There was a 5% mortality rate in dermatomyositis patients due to infections. Treated dermatomyositis patients demonstrate the most significant improvement in strength during the first six-to-twelve months following their initial clinical assessment. Additional prospective studies are needed to determine the relative benefit of select immunosuppressant agents in preserving strength and reducing corticosteroid use in dermatomyositis.

Quality of life measures for myasthenia gravis and evaluation of non-motor symptoms

Health‐related quality of life measures have become an important tool in measuring clinical outcomes. Disease‐specific health‐related quality of life scales, particularly in diseases that might fluctuate, can draw attention to non‐motor symptoms and guide symptom management. The following review provides an overview of quality of life (QOL) with a focus of disease‐specific QOL measures for myasthenia gravis. We also review the current understanding of non‐motor symptoms in myasthenia gravis and suggest that QOL measures might be a useful way of accounting for these symptoms. After reading the review, the reader will have a better understanding of QOL measures and how they can be used for patient care and clinical research.

Construction and validation of the chronic acquired polyneuropathy patient‐reported index, “CAP‐PRI:” a disease‐specific, health‐related quality of life instrument

Introduction: Generic health‐related quality‐of‐life (HRQOL) patient‐reported outcome measures have been used in patients with chronic immune‐mediated polyneuropathies. We have created a disease‐specific HRQOL instrument. Methods: The chronic acquired polyneuropathy patient‐reported index (CAP‐PRI) was developed and validated in multiple steps. Items were initially generated through patient and specialist input. The performance of the preliminary 20 items was analyzed via a prospective, 5‐center study involving chronic immune‐mediated polyneuropathy patients. Results: Data analysis suggested modification to a 15‐item scale with 3 response categories rather than 5. The final CAP‐PRI was validated in another prospective, 5‐center study. The CAP‐PRI appeared to be a unidimensional outcome measure that fit the Rasch model in our multicenter cohort. It correlated appropriately with outcome measures commonly used in this patient population. Conclusions: The CAP‐PRI is a simple disease‐specific HRQOL measure that appears to be useful for clinical care and possibly also for clinical trials. Muscle Nerve 54: 9–17, 2016

Splenic marginal zone lymphoma: An indolent malignancy leading to the development of neurolymphomatosis

Acute neuropathic pain and weakness with a sensory level in a patient with a history of lymphoma has a broad differential diagnosis. Evaluation of such a presentation often includes MRI, neurophysiologic studies, and cerebrospinal fluid evaluation. We report a patient with splenic marginal zone lymphoma who developed acute weakness, sensory loss, and neuropathic pain due to neurolymphomatosis.

Plexus and peripheral nerve metastasis

Cancer in the form of solid tumors, leukemia, and lymphoma can infiltrate and metastasize to the peripheral nervous system, including the cranial nerves, nerve roots, cervical, brachial and lumbosacral plexuses, and, rarely, the peripheral nerves. This review discusses the presentation, diagnostic evaluation, and treatment options for metastatic lesions to these components of the peripheral nervous system and is organized based on the anatomic distribution. As skull base metastases (also discussed in Chapter 14) result in cranial neuropathies, these will be covered in detail, as well as cancers that directly infiltrate the cranial nerves. Particular emphasis is placed on the clinical, imaging, and electrodiagnostic features that differentiate neoplastic plexopathies from radiation-induced plexopathies. Neurolymphomatosis, in which malignant lymphocytes invade the cranial nerves, nerve roots, brachial and lumbosacral plexuses, and peripheral nerves, is a rare manifestation of lymphoma and leukemia. Diagnoses of neurolymphomatosis are often missed or delayed given its varied presentations, resulting in poorer outcomes. Thus this disease will also be discussed in depth.

Validation of a simple disease-specific, quality-of-life measure for diabetic polyneuropathy: CAPPRI

Objective We studied the performance of a 15-item, health-related quality-of-life polyneuropathy scale in the clinic setting in patients with diabetic distal sensorimotor polyneuropathy (DSPN). Methods Patients with DSPN from 11 academic sites completed a total of 231 Chronic Acquired Polyneuropathy Patient-Reported Index (CAPPRI) scales during their clinic visits. Conventional and modern psychometric analyses were performed on the completed forms. Results Conventional and modern analyses generally indicated excellent psychometric properties of the CAPPRI in patients with DSPN. For example, the CAPPRI demonstrated unidimensionality and performed like an interval-level scale. Conclusion Attributes of the CAPPRI for DSPN include ease of use and interpretation; unidimensionality, allowing scores to be summed; adequate coverage of disease severity; and the scales ability to address relevant life domains. Furthermore, the CAPPRI is free and in the public domain. The CAPPRI may assist the clinician and patient with DSPN in estimating disease-specific quality of life, especially in terms of pain, sleep, psychological well-being, and everyday function. The CAPPRI may be most useful in the everyday clinical setting but merits further study in this setting, as well as the clinical trial setting.

Gluteal compartment syndrome with neurologic impairment: Report of 2 cases and review of the literature

Introduction: We describe two patients who developed gluteal compartment syndrome (GCS) in the context of drug overdose. One patient developed a sciatic neuropathy, and one patient developed a lumbosacral plexopathy. Methods: We reviewed the literature of atraumatic GCS and resultant neurological impairment. Results: We reviewed 26 cases (our two cases and 24 previously published cases) of GCS and neurological impairment. All patients developed GCS in the context of drug or alcohol overdose. Creatine kinase was markedly elevated in all patients in which it was tested, and most patients developed renal failure. Seventeen patients had a fasciotomy, and 9 patients were managed conservatively. There appeared to be a trend toward worse prognosis in the conservatively managed group. Discussion: Neurologists should be aware of GCS. Immediate recognition facilitates consideration of further diagnostic testing, including intracompartmental pressure measurement and consideration of surgical decompression, which may influence outcome. Muscle Nerve, 57: 325–330, 2018