Clinical Reasoning: A 55-Year-Old Woman With Painless Hand Weakness and Atrophy.

Hand weakness is a frequent chief concern in neurology practice. We report a case of a 55-year-old woman presenting with a chronic, gradually worsening right hand weakness and atrophy, selectively affecting the thenar muscles, without any sensory symptoms. She had a history of carpal tunnel syndrome and previously underwent surgical carpal tunnel release. This case delves into the differential diagnosis of hand weakness and atrophy, emphasizing the significance of myotomal innervation in intrinsic hand muscles. Furthermore, it outlines a systematic approach to diagnosing an uncommon cause for a common clinical presentation, offering a comprehensive differential diagnosis, and exploring various possible causes.

Greater Number of Plasma Exchanges Does Not Improve Outcome in Myasthenic Crisis.

OBJECTIVES: To determine the relationship between the number of plasma exchanges and clinical outcome in patients experiencing myasthenic crisis. METHODS: We retrospectively reviewed all episodes of myasthenia gravis exacerbation/crisis who received plasmapheresis in patients admitted to a single-center tertiary care referral center from July 2008 to July 2017. We performed statistical analyses to determine whether the increased number of plasma exchanges improves the primary outcome (hospital length of stay) and the secondary outcome (disposition to home, skilled nursing facility, long-term acute care hospital, or death). RESULTS: There is neither clinically observable nor statistically significant improvement in length of stay or disposition on discharge in patients who received 6 or greater sessions of plasmapheresis. CONCLUSIONS: This study provides class IV evidence that extending the number of plasma exchanges beyond 5 does not correlate with decreased hospital length of stay or improved discharge disposition in patients experiencing myasthenic crisis.

Evidence-based guideline: Neuromuscular ultrasound for the diagnosis of ulnar neuropathy at the elbow.

INTRODUCTION/AIMS: The purpose of this literature review is to develop an evidence-based guideline for the use of neuromuscular ultrasound in the diagnosis of ulnar neuropathy at the elbow (UNE). The proposed research question was: "In patients with suspected UNE, does ulnar nerve enlargement as measured with ultrasound accurately identify those patients with UNE?" METHODS: A systematic review and meta-analysis was performed, and studies were classified according to American Academy of Neurology criteria for rating articles for diagnostic accuracy. RESULTS: Based on Class I evidence in four studies, it is probable that neuromuscular ultrasound measurement of the ulnar nerve at the elbow, either of diameter or cross-sectional area (CSA), is accurate for the diagnosis of UNE. RECOMMENDATION: For patients with symptoms and signs suggestive of ulnar neuropathy, clinicians should offer ultrasonographic measurement of ulnar nerve cross-sectional area or diameter to confirm the diagnosis and localize the site of compression (Level B).

The Incidence of Amyotrophic Lateral Sclerosis in Ohio 2016-2018: The Ohio Population-Based ALS Registry.

INTRODUCTION: Amyotrophic lateral sclerosis (ALS) is a fatal, neuromuscular disease with no cure. ALS incidence rates have not been assessed specifically in Ohio, yet the state contains both metropolitan and rural areas with a variety of environmental factors that could contribute to disease etiology. We report the incidence of ALS in Ohio residents diagnosed from October 2016 through September 2018. METHODS: We engaged practitioners from 9 Ohio sites to identify newly diagnosed ALS patients and to complete case report forms with demographic and clinical information. ALS was diagnosed according to the Awaji criteria and classified as either definite, probable, or possible. We developed a method to estimate missing cases using a Poisson regression model to impute cases in counties with evidence of undercounting. RESULTS: We identified 333 newly diagnosed ALS patients residing in Ohio during the 2-year index period and found incidence rates varied in the 88 state counties. After incorporating the estimated 27% of missing cases, the corrected crude annual incidence was 1.96/100,000 person-years, and the age- and gender-standardized incidence was 1.71/100,000 person-years (standardized to the 2010 US census). DISCUSSION/CONCLUSION: The estimated Ohio incidence of ALS is overall similar to that reported in other states in the USA. This study reveals a geospatial variation in incidence within the state, and areas with higher rates warrant future investigation.

Neuropathy associated with IgA monoclonal Gammopathy. A harbinger of AL amyloidosis.

Peripheral neuropathy is seen in 15% of patients with IgA monoclonal gammopathy. Treatment and prognosis of dysproteinemic neuropathy is usually guided by the underlying plasma cell disorders, which could be either benign or malignant. The true incidence of hematologic malignancy in patients with neuropathy associated with IgA monoclonal gammopathy is not known. However, patients with IgA M-protein are generally at increased risk for malignant transformation. Since neuropathy may be the first and only organ involvement, neurologists are key contributors in identifying each patient's plasma cell dyscrasia. We report two patients who presented with severe progressive polyneuropathy, had a detectable low-level IgA lambda paraproteinemia dismissed as incidental. Both were diagnosed later with a combination of malignant plasma cell dyscrasia and AL amyloidosis resulting in multiorgan failure and death. Both patients demonstrated red flags for malignant progression including abnormal serum free light chain, rapidly progressive debilitating neuropathy refractory to immunotherapy, prominent autonomic dysfunction, and weight loss. In summary, patients with IgA monoclonal gammopathy presenting with polyneuropathy can be at risk for malignant transformation. Failure to investigate for hematologic malignancy and AL amyloidosis may cause significant delays in treatment and result in fatal outcomes.

Risk factors for amyotrophic lateral sclerosis: A regional United States case-control study.

Most amyotrophic lateral sclerosis (ALS) cases are considered sporadic, without a known genetic basis, and environmental exposures are thought to play a causal role. To learn more about sporadic ALS etiology, we recruited n = 188 ALS patients from northern New England and Ohio and matched controls 2:1 from the general population of the same regions. Questionnaires evaluated the association between a variety of lifestyle, behavioral (ie, hobbies and activities), and occupational factors and the risk of ALS, including the duration of time between exposure and ALS onset, and exposure frequency. Head trauma was associated with increased ALS risk (adjusted odds ratio [OR] 1.60 95% confidence interval [CI] 1.04-2.45), with significantly greater effects for injuries occurring 10 or more years prior to symptom onset (P = .037). ALS risk was increased for those reporting severe electrical burns (adjusted OR 2.86, 95% CI 1.37-6.03), with odds ratios highest for burns after age 30 (OR 3.14), and for burns 10 or more years prior to symptom onset (OR 3.09). Hobbies involving lead were the most strongly associated with ALS risk (adjusted OR 2.92, 95% CI 1.45-5.91). Exposures to lead 20 or more years prior to diagnosis had larger effect sizes compared to those occurring more recently. Holding a job in mechanics, painting, or construction was associated with ALS. The identification of these specific environmental factors associated with ALS highlight the need for future prospective and laboratory studies to assess causality, biological mechanisms, and find prevention or treatment opportunities.

Spinal cord injury level and Phrenic Nerve Conduction Studies do not predict diaphragm pacing success or failure- all patients should undergo diagnostic laparoscopy.

BACKGROUND: Diaphragm Pacing(DP) demonstrates benefits over mechanical ventilation(MV) for spinal cord injured(SCI) patients. The hypothesis of this report is that phrenic nerve conduction study(PNCS) results cannot differentiate success or failure in selection of patients for DP. Direct surgical evaluation of the diaphragm should be performed. METHODS: Observational report of prospective databases of patients undergoing laparoscopic evaluation of their diaphragms to assess for ability to stimulate to cause contraction for ventilation. RESULTS: In 50 SCI patients who could not be weaned from MV, PNCS results showed latencies in stimulated patients (n = 44) and non-stimulated(n = 6) overlapped (7.8 ± 2.5 ms vs 9.4 ± 2.8 ms) and the null hypothesis cannot be rejected (p-value>0.05). Amplitudes overlapped (0.4 ± 0.2 mV vs 0.2 ± 0.2 mV) and the null hypotheses cannot be rejected (P-value >0.05). In 125 non SCI patients with diaphragm paralysis, there were 78(62.4%) with false negative PNCS. CONCLUSION: PNCS are inadequate pre-operative studies. Direct laparoscopic evaluation should be offered for all SCI patients to receive the benefit of DP.

Minimal manifestation status and prednisone withdrawal in the MGTX trial.

OBJECTIVE: To examine whether sustained minimal manifestation status (MMS) with complete withdrawal of prednisone is better achieved in thymectomized patients with myasthenia gravis (MG). METHODS: This study is a post hoc analysis of data from a randomized trial of thymectomy in MG (Thymectomy Trial in Non-Thymomatous Myasthenia Gravis Patients Receiving Prednisone Therapy [MGTX]). MGTX was a multicenter, randomized, rater-blinded 3-year trial that was followed by a voluntary 2-year extension for patients with acetylcholine receptor (AChR) antibody-positive MG without thymoma. Patients were randomized 1:1 to thymectomy plus prednisone vs prednisone alone. Participants were age 18-65 years at enrollment with disease duration less than 5 years. All patients received oral prednisone titrated up to 100 mg on alternate days until they achieved MMS, which prompted a standardized prednisone taper as long as MMS was maintained. The achievement rate of sustained MMS (no symptoms of MG for 6 months) with complete withdrawal of prednisone was compared between the thymectomy plus prednisone and prednisone alone groups. RESULTS: Patients with MG in the thymectomy plus prednisone group achieved sustained MMS with complete withdrawal of prednisone more frequently (64% vs 38%) and quickly compared to the prednisone alone group (median time 30 months vs no median time achieved, p < 0.001) over the 5-year study period. Prednisone-associated adverse symptoms were more frequent in the prednisone alone group and distress level increased with higher doses of prednisone. CONCLUSIONS: Thymectomy benefits patients with MG by increasing the likelihood of achieving sustained MMS with complete withdrawal of prednisone. CLINICALTRIALSGOV IDENTIFIER: NCT00294658. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for patients with generalized MG with AChR antibody, those receiving thymectomy plus prednisone are more likely to attain sustained MMS and complete prednisone withdrawal than those on prednisone alone.

Autoimmune musicogenic epilepsy associated with anti-glutamic acid decarboxylase antibodies and Stiff-person syndrome.

Epilepsy should be suspected in patients with Stiff-person syndrome and new onset paroxysmal episodes. Musicogenic epilepsy may be a manifestation of anti-GAD-Ab spectrum, supporting an autoimmune workup in these patients. Appropriate treatment is not well established, and immunotherapy should be considered in patients with only partial response to antiepileptic drugs.

Peripheral nerve hyperexcitability.

Neuromyotonic and myokymic discharges are abnormal electrical muscular discharges caused by ectopic discharges from motor axons and represent the hallmarks of peripheral nerve hyperexcitability. Neuromyotonic discharges are specific for peripheral nerve hyperexcitability syndromes, whereas myokymic discharges may occur either focally or in a more generalized fashion in many other peripheral nerve disorders. Isaacs syndrome and Morvan syndrome are rare acquired peripheral nerve hyperexcitability disorders that share common clinical features and are often associated with elevated voltage-gated potassium channel-complex antibodies. Central nervous system symptomatology is more common in Morvan syndrome, which also overlaps with limbic encephalitis. Cramp-fasciculation syndrome, a more common syndrome, may represent a milder form of peripheral nerve hyperexcitability. Peripheral nerve hyperexcitability syndromes should be distinguished from stiff person syndrome, myotonic disorders, and rippling muscle disease. When severe, Isaacs syndrome and Morvan syndrome may be disabling but often respond to membrane-stabilizing drugs and immunomodulatory treatments. The electrophysiologic features of these disorders are described.

Rescue treatment in patients with poorly responsive Guillain-Barre syndrome.

OBJECTIVES: To evaluate the effectiveness of rescue treatment (intravenous immunoglobulin or plasma exchange) in patients with Guillain-Barre syndrome who did not respond or deteriorated after the initial management with intravenous immunoglobulin. METHODS: We performed a retrospective review of the medical records of patients who responded poorly or did not respond to intravenous immunoglobulin treatment. The disability parameters of those who received second-line treatment with intravenous immunoglobulin or plasma exchange (20 patients) were compared with those who did not receive second-line treatment (19 patients). RESULTS: There was a statistically significant improvement in disability scores at 1 month in the patients who received the rescue treatment (p = 0.033). However, there was no significant difference in the disability scores at 3 and 6 months, or in length of intensive care unit stay. CONCLUSION: Our study showed that a second course of treatment to carefully selected patients may be beneficial.

Long-term effect of thymectomy plus prednisone versus prednisone alone in patients with non-thymomatous myasthenia gravis: 2-year extension of the MGTX randomised trial.

BACKGROUND: The Thymectomy Trial in Non-Thymomatous Myasthenia Gravis Patients Receiving Prednisone (MGTX) showed that thymectomy combined with prednisone was superior to prednisone alone in improving clinical status as measured by the Quantitative Myasthenia Gravis (QMG) score in patients with generalised non-thymomatous myasthenia gravis at 3 years. We investigated the long-term effects of thymectomy up to 5 years on clinical status, medication requirements, and adverse events. METHODS: We did a rater-blinded 2-year extension study at 36 centres in 15 countries for all patients who completed the randomised controlled MGTX and were willing to participate. MGTX patients were aged 18 to 65 years at enrolment, had generalised non-thymomatous myasthenia gravis of less than 5 years' duration, had acetylcholine receptor antibody titres of 1·00 nmol/L or higher (or concentrations of 0·50-0·99 nmol/L if diagnosis was confirmed by positive edrophonium or abnormal repetitive nerve stimulation, or abnormal single fibre electromyography), had Myasthenia Gravis Foundation of America Clinical Classification Class II-IV disease, and were on optimal anticholinesterase therapy with or without oral corticosteroids. In MGTX, patients were randomly assigned (1:1) to either thymectomy plus prednisone or prednisone alone. All patients in both groups received oral prednisone at doses titrated up to 100 mg on alternate days until they achieved minimal manifestation status. The primary endpoints of the extension phase were the time-weighted means of the QMG score and alternate-day prednisone dose from month 0 to month 60. Analyses were by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00294658. It is closed to new participants, with follow-up completed. FINDINGS: Of the 111 patients who completed the 3-year MGTX, 68 (61%) entered the extension study between Sept 1, 2009, and Aug 26, 2015 (33 in the prednisone alone group and 35 in the prednisone plus thymectomy group). 50 (74%) patients completed the 60-month assessment, 24 in the prednisone alone group and 26 in the prednisone plus thymectomy group. At 5 years, patients in the thymectomy plus prednisone group had significantly lower time-weighted mean QMG scores (5·47 [SD 3·87] vs 9·34 [5·08]; p=0·0007) and mean alternate-day prednisone doses (24 mg [SD 21] vs 48 mg [29]; p=0·0002) than did those in the prednisone alone group. 14 (42%) of 33 patients in the prednisone group, and 12 (34%) of 35 in the thymectomy plus prednisone group, had at least one adverse event by month 60. No treatment-related deaths were reported during the extension phase. INTERPRETATION: At 5 years, thymectomy plus prednisone continues to confer benefits in patients with generalised non-thymomatous myasthenia gravis compared with prednisone alone. Although caution is appropriate when generalising our findings because of the small sample size of our study, they nevertheless provide further support for the benefits of thymectomy in patients with generalised non-thymomatous myasthenia gravis. FUNDING: National Institutes of Health, National Institute of Neurological Disorders and Stroke.

Chronic immune sensorimotor polyradiculopathy: Report of a case series.

INTRODUCTION: Chronic immune sensorimotor polyradiculopathy (CISMP) is a chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) variant affecting both sensory and motor nerve roots without evidence of peripheral nerve demyelination. METHODS: We report a case series of 9 patients with CISMP, identified from 2 tertiary centers. Clinical, electrodiagnostic, and neuroradiologic features, and treatment responses, were retrospectively reviewed. RESULTS: Patients presented with sensorimotor deficits and hypo-/areflexia, predominantly involving lower extremities. Three had cranial nerve involvement. Electrodiagnostic findings in all patients localized to roots proximal to dorsal root ganglia, without evidence of peripheral nerve demyelination. Cerebrospinal fluid examination revealed an albuminocytologic association. Eight patients exhibited gadolinium enhancement and thickening of multiple spinal nerve roots and/or cranial nerves. All patients demonstrated good responses to immunotherapies. DISCUSSION: CISMP is similar to CIDP in many aspects, but lacks typical electrodiagnostic findings of peripheral nerve demyelination. It is important to recognize this unusual and treatable entity. Muscle Nerve 59:658-664, 2019.

Long-term experience with diaphragm pacing for traumatic spinal cord injury: Early implantation should be considered.

BACKGROUND: Cervical spinal cord injury can result in catastrophic respiratory failure requiring mechanical ventilation with high morbidity, mortality, and cost. Diaphragm pacing was developed to replace/decrease mechanical ventilation. We report the largest long-term results in traumatic cervical spinal cord injury. METHODS: In this retrospective review of prospective institutional review board protocols, all patients underwent laparoscopic diaphragm mapping and implantation of electrodes for diaphragm strengthening and ventilator weaning. RESULTS: From 2000 to 2017, 92 patients out of 486 diaphragm pacing implants met the criteria. The age at time of injury ranged from birth to 74 years (average: 27 years). Time on mechanical ventilation was an average of 47.5 months (range, 6 days to 25 years, median = 1.58 years). Eighty-eight percent of patients achieved the minimum of 4 hours of pacing. Fifty-six patients (60.8%) used diaphragm pacing 24 hours a day. Five patients had full recovery of breathing with subsequent diaphragm pacing removal. Median survival was 22.2 years (95% confidence interval: 14.0-not reached) with only 31 deaths. Subgroup analysis revealed that earlier diaphragm pacing implantation leads to greater 24-hour use of diaphragm pacing and no need for any mechanical ventilation. CONCLUSION: Diaphragm pacing can successfully decrease the need for mechanical ventilation in traumatic cervical spinal cord injury. Earlier implantation should be considered.

Autoimmune Neuromuscular Diseases Induced by Immunomodulating Drugs.

Immunomodulating drugs are widely used in autoimmune, transplant, and cancer patients. However, these drugs are associated with various autoimmune neuromuscular diseases such as demyelinating polyneuropathy, myasthenia gravis, and myositis. Early recognition of these complications and immediately terminating these drugs are very essential since some are life-threatening conditions. This review provides a general overview of drug-induced autoimmunity and autoimmune neuromuscular diseases associated with tumor necrosis factor alpha (TNF-α) antagonists, immune checkpoint inhibitors, and interferon (IFN) type 1 (IFN-ß and IFN-α).

Guillain-Barré Syndrome Triggered by Immune Checkpoint Inhibitors: A Case Report and Literature Review.

Immune checkpoint inhibitors, used as immunotherapy in the treatment of melanoma and refractory cancer, may trigger autoimmune disorders. We describe a case of Guillain-Barré syndrome (GBS) after the treatment with ipilimumab and nivolumab and review 4 other reported cases. We confirmed the diagnosis of GBS by electrodiagnostic and cerebrospinal fluid studies. Electrodiagnostic results showed findings consistent with acquired demyelinating polyneuropathy and cerebrospinal fluid showed albuminocytologic dissociation. All patients were treated with intravenous immunoglobulin or other immunomodulating therapy. Among 5 cases which include our patient, 2 did well, 1 did not improve, and 2 died of respiratory insufficiency and multiorgan failure. Enhancing T-cell activation from immune checkpoint inhibitors may trigger GBS which should be suspected when progressive weakness and areflexia occur after treatment with immune checkpoint inhibitors.