Semi-supervised exercise training program more effective for individuals with postural orthostatic tachycardia syndrome in randomized controlled trial

PURPOSE

Exercise like any medication requires the correct dose; to be effective the appropriate frequency, duration, and intensity are necessary. This study aimed to assess if a semi-supervised exercise training (ET) program would be more effective at improving aerobic fitness (VO2PEAK), exercise tolerance, and symptoms in individuals with postural orthostatic tachycardia syndrome (POTS) compared to the standard of care (SOC).

METHODS

Subjects were randomized to either the ET or SOC groups (n 26 vs. 23; age 33 ± 11 vs. 37 ± 10 years; VO2PEAK 66 ± 15 vs. 62 ± 15% predicted, ET vs. SOC respectively, p > 0.05). Composite Autonomic Symptom Score (COMPASS 31), 10 min stand test, and cardiopulmonary exercise test were performed at baseline and following 12 weeks. The ET group received an exercise consultation and eight semi-supervised in-person or virtual exercise sessions.

RESULTS

The ET group demonstrated a greater improvement in VO2PEAK, higher or longer tolerance for baseline peak workload, and more often had a delayed symptom onset with exercise than the SOC group (ΔVO2PEAK 3.4 vs. - 0.2 mL/min/kg, p < 0.0001, ΔWorkload 19 ± 17 vs. 0 ± 10 W; Workload time 63 ± 29 vs. 22 ± 30 s; onset-delay 80% vs. 30%, p < 0.05). Individuals in the ET group reported a significant improvement in orthostatic intolerance domain score (p = 0.02), but there was not a significant difference in the improvement in total COMPASS score (- 11.38 vs. - 6.49, p = 0.09).

CONCLUSION

Exercise training was more effective with greater improvements in aerobic fitness, orthostatic symptoms, and exercise tolerance for individuals with POTS when intensity and progression were personalized and delivered with minimal supervision compared to the SOC.

Standardized Autonomic Testing in Patients With Probable Radiation-Induced Afferent Baroreflex Failure

Injury of the afferent limb of the baroreflex from neck radiation causes radiation-induced afferent baroreflex failure (R-ABF). Identification and management of R-ABF is challenging. We aimed to investigate the pattern of autonomic dysfunction on standardized autonomic testing in patients with probable R-ABF. We retrospectively analyzed all autonomic reflex screens performed at Mayo Clinic in Rochester, MN, between 2000 and 2020 in patients with probable R-ABF. Additional tests reviewed included ambulatory blood pressure monitoring, plasma norepinephrine, and thermoregulatory sweat test. We identified 90 patients with probable R-ABF. Median total composite autonomic severity score (range, 0-10) was 7 (interquartile range, 6-7). Cardiovascular adrenergic impairment was seen in 85 patients (94.4%), increased blood pressure recovery time after Valsalva maneuver in 71 patients (78.9%; median 17.4 seconds), and orthostatic hypotension in 68 patients (75.6%). Cardiovagal impairment was demonstrated by abnormal heart rate responses to deep breathing (79.5%), Valsalva ratio (87.2%), and vagal baroreflex sensitivity (57.9%). Plasma norepinephrine was elevated and rose appropriately upon standing (722-1207 pg/mL). Ambulatory blood pressure monitoring revealed hypertension, postural hypotension, hypertensive surges, tachycardia, and absence of nocturnal dipping. Blood pressure lability correlated with impaired vagal baroreflex function. Postganglionic sympathetic sudomotor function was normal in most cases; the most frequent thermoregulatory sweat test finding was focal neck anhidrosis (78.9%). Standardized autonomic testing in R-ABF demonstrates cardiovascular adrenergic impairment with orthostatic hypotension, blood pressure lability, and elevated plasma norepinephrine. Cardiovagal impairment is common, while sudomotor deficits are limited to direct radiation effects.

Functional status in postural tachycardia syndrome

Introduction

Postural tachycardia syndrome is a form of orthostatic intolerance that often leads to functional impairment.

Methods

This survey explored functional status and impact of symptoms in adults ( n = 958) ages 18 to 60 (M = 32.63 ± 10.52 years, 96.7% female) with postural tachycardia syndrome.

Results

Individuals reported an average of 11 daily life activities impacted by postural tachycardia syndrome with high levels of self-perceived disability. Additionally, 93.4% reported some degree of cognitive impairment and falls occurred in 55.3% of participants annually. Despite frequent falls and functional impairment, participants infrequently (26.9%) utilized therapy services.

Conclusion

Individuals with postural tachycardia syndrome are at an increased risk of experiencing disability and often require assistance with daily activities. Further research is necessary to understand the potential role of therapy in improving function and quality of life.

Postural orthostatic tachycardia syndrome (POTS): Priorities for POTS care and research from a 2019 National Institutes of Health Expert Consensus Meeting - Part 2

The National Institutes of Health hosted a workshop in 2019 to build consensus around the current state of understanding of the pathophysiology of postural orthostatic tachycardia syndrome (POTS) and to identify knowledge gaps that must be addressed to enhance clinical care of POTS patients through research. This second (of two) articles summarizes current knowledge gaps, and outlines the clinical and research priorities for POTS.

POTS is a complex, multi-system, chronic disorder of the autonomic nervous system characterized by orthostatic intolerance and orthostatic tachycardia without hypotension. Patients often experience a host of other related disabling symptoms. The functional and economic impacts of this disorder are significant. The pathophysiology remains incompletely understood.

Beyond the significant gaps in understanding the disorder itself, there is a paucity of evidence to guide treatment which can contribute to suboptimal care for this patient population. The vast majority of physicians have minimal to no familiarity or training in the assessment and management of POTS.

Funding for POTS research remains very low relative to the size of the patient population and impact of the syndrome. In addition to efforts to improve awareness and physician education, an investment in research infrastructure including the development of standardized disease-specific evaluation tools and outcome measures is needed to facilitate effective collaborative research. A national POTS research consortium could facilitate well-controlled multidisciplinary clinical research studies and therapeutic trials. These priorities will require a substantial increase in the number of research investigators and the amount of research funding in this area.

Postural orthostatic tachycardia syndrome (POTS): State of the science and clinical care from a 2019 National Institutes of Health Expert Consensus Meeting - Part 1

Postural orthostatic tachycardia syndrome (POTS) is a chronic and often disabling disorder characterized by orthostatic intolerance with excessive heart rate increase without hypotension during upright posture. Patients often experience a constellation of other typical symptoms including fatigue, exercise intolerance and gastrointestinal distress. A typical patient with POTS is a female of child-bearing age, who often first displays symptoms in adolescence. The onset of POTS may be precipitated by immunological stressors such as a viral infection. A variety of pathophysiologies are involved in the abnormal postural tachycardia response; however, the pathophysiology of the syndrome is incompletely understood and undoubtedly multifaceted. Clinicians and researchers focused on POTS convened at the National Institutes of Health in July 2019 to discuss the current state of understanding of the pathophysiology of POTS and to identify priorities for POTS research. This article, the first of two articles summarizing the information discussed at this meeting, summarizes the current understanding of this disorder and best practices for clinical care. The evaluation of a patient with suspected POTS should seek to establish the diagnosis, identify co-morbid conditions, and exclude conditions that could cause or mimic the syndrome. Once diagnosed, management typically begins with patient education and non-pharmacologic treatment options. Various medications are often used to address specific symptoms, but there are currently no FDA-approved medications for the treatment of POTS, and evidence for many of the medications used to treat POTS is not robust.

Natural History of Afferent Baroreflex Failure in Adults

OBJECTIVE

To describe the natural history of afferent baroreflex failure (ABF) based on systematic review of clinical and laboratory data in patients with a diagnosis of ABF at Mayo Clinic Rochester.

METHODS

We performed a retrospective chart review of all patients who underwent standardized autonomic reflex testing between 2000 and 2020 and had confirmation of the diagnosis of ABF by an autonomic disorders specialist. Patients were identified using a data repository of medical records. Variables included demographic, all-cause mortality, medications, ABF manifestations, comorbidities, and laboratory (autonomic testing, blood pressure monitoring, echocardiogram, brain imaging, plasma catecholamines, serum sodium level, and kidney function tests).

RESULTS

A total of 104 patients with ABF were identified. Head and neck radiation was the most common etiology (86.5%), followed by neck surgery (5.8%) and other causes (7.7%). The most common findings were hypertension (87.5%), fluctuating blood pressure (78.8%), orthostatic hypotension (91.3%), syncope (58.6%), headache (22.1%), and tachycardia (20.2%). Patients commonly received antihypertensives (66.3%), pressor agents (41.3%), or a combination of both (19.2%). The median latency from completion of radiation to ABF was longer compared to the latency in the surgery group (p < 0.0001). Comorbidities, including complications from neck radiation, were frequently seen and all-cause mortality was 39.4% over a 20-year period.

CONCLUSIONS

ABF should be suspected in patients with prior head and neck cancer treated by radiation or surgery who present with labile hypertension and orthostatic hypotension. Management may require both antihypertensive and pressor medications. The morbidity and mortality in ABF are high.

COVID-19 Dysautonomia

Objective: To report a case series of dysautonomia associated with COVID-19 infection.

Methods: This is a retrospective review of patients evaluated in the autonomic clinic at our institution with suspected signs and symptoms of dysautonomia who underwent formal evaluation, including autonomic testing.

Results: Six patients were identified with signs and symptoms suggestive of dysautonomia who underwent autonomic testing. All patients had symptoms typical of COVID-19 infection, though none were hospitalized for these or other symptoms. All patients reported symptoms of postural lightheadedness and near-syncope, fatigue, and activity intolerance. Five patients reported the onset of autonomic symptoms concomitant with other COVID-19 symptoms, with the other patient reporting symptom onset 6 weeks following initial COVID-19 symptoms. Autonomic testing demonstrated an excessive postural tachycardia in 4 patients, a hypertensive response with head-up tilt in 3 patients, orthostatic hypotension in 1 patient, and sudomotor impairment in 1 of the patients with excessive postural tachycardia.

Conclusions: We present clinical features and results of autonomic testing in 6 patients with a history COVID-19 infection. While all patients reported typical features of orthostatic intolerance, fatigue, and activity intolerance, the results of autonomic testing were heterogenous, with orthostatic hypotension in 1 patient, excessive postural tachycardia typical of postural tachycardia syndrome in 4 patients, and postural hypertension in 3 patients.

Tumor Necrosis Factor-Alpha Signaling May Contribute to Chronic West Nile Virus Post-infectious Proinflammatory State

Background: West Nile virus (WNV) causes a spectrum of human disease ranging from a febrile illness (WNV fever) to severe neuroinvasive disease (meningitis, encephalitis, acute flaccid paralysis). Since WNV gained entry into North America in 1999, clinicians caring for WNV survivors have observed persistent neurological symptoms occurring long-after the production of neutralizing antibodies and clearance of the virus. Accordingly, alternative pathogeneses other than direct viral invasion have been hypothesized to explain these post-infectious symptoms. The dominant hypothesis is that antiviral inflammatory responses triggered initially to clear WNV may persist to promote a post-infectious proinflammatory state.

Methods: In 4 serologically-confirmed WNV patients with persistent post-infectious symptoms (3 WNV fever, 1 neuroinvasive disease), we ordered a comprehensive cytokine panel at weeks 8, 10, 12, and 36 months post-onset of illness, respectively, to better understand the pathophysiology of the protracted symptoms.

Results: All patients had abnormally elevated tumor necrosis factor alpha (TNF-α), a major molecule triggering antiviral cytokines and chronic inflammation in many human autoimmune diseases, but heretofore not reported to be upregulated in human WNV infection. Three patients also had elevations of other proinflammatory proteins. Major symptoms included fatigue, arthralgias, myalgias, generalized or multifocal pain or weakness, imbalance, headaches, cognitive problems, and symptoms of dysautonomia.

Conclusion: The findings provide support for an extended post-infectious proinflammatory state that may contribute to chronic inflammation and long-term morbidity in some WNV survivors and further suggest that TNF-α may play a pathogenic role in initiating this inflammatory environment. Clinical trials may be warranted to determine if TNF-α inhibitors or other immunosuppressive agents can improve patient outcomes.

Rheumatoid Meningitis: Clinical Characteristics, Diagnostic Evaluation, and Treatment

Background and Purpose

Due to the potential for high mortality and neurologic complications of rheumatoid meningitis (RM), awaiting biopsy confirmation may delay vital treatment intervention. Our aim was to describe the clinical presentations of RM in our population and determine whether meningeal biopsy impacted diagnosis, treatment, and outcomes.

Methods

A retrospective chart review was completed for patients at Mayo Clinic with a diagnosis of RM within the last 28 years. Those with identified alternative inflammatory, infectious, or neoplastic causes of pachymeningitis or leptomeningitis were excluded.

Results

Fourteen patients meeting inclusion/exclusion criteria were identified. All patients were positive for rheumatoid factor or cyclic citrullinated peptide. All patients had magnetic resonance imaging abnormalities characterized by pachymeningeal and/or leptomeningeal enhancement. Of the 10 patients who underwent biopsy, nonspecific findings were seen in 74%. All patients except one were treated with corticosteroids with subsequent symptomatic improvement. Radiographic improvement or resolution was seen in 10 (83%) of 12. Patients improved with corticosteroid treatment, including those who were diagnosed with RM on clinical basis without undergoing a biopsy as well.

Conclusions

This retrospective review displays the myriad of clinical presentations of RM. It also suggests that with appropriate exclusion of infectious, neoplastic, and other autoimmune etiologies, biopsy may not be necessary to initiate treatment.

The spectrum of acute cardiopulmonary events associated with multiple sclerosis exacerbations

Diverse acute neurological injuries may cause acute cardiopulmonary events including neurogenic pulmonary edema (NPE) and neurogenic stunned myocardium (NSM). The mechanism is probably mediated by sympathetic nervous system activation. Focal central nervous system (CNS) lesions, such as demyelinating lesions in multiple sclerosis (MS), may also cause cardiopulmonary disturbances. We aim to review the acute cardiopulmonary events associated with MS relapses. We performed a literature search using PubMed, and selected case reports of acute cardiac and/or pulmonary events related to MS exacerbations. We grouped these events into three categories: 1) NPE with normal cardiac function; 2) NSM and Takotsubo cardiomyopathy (TTC); 3) coexisting myocardial dysfunction and pulmonary edema. In some cases, cardiac and pulmonary symptoms preceded the onset of neurological symptoms. The majority of cases were associated with acute demyelinating lesions located in the medulla. Acute brainstem MS relapses, with demyelinating lesions affecting the medulla, may cause acute cardiac and pulmonary events presumably secondary to sympathetic hyperstimulation. Specific regions in the medulla that regulate cardiac function, systemic blood pressure and pulmonary hydrostatic pressure seem to be responsible for these events.

Abnormal respiratory patterns in a series of post-concussive patients

Background

Autonomic nervous system dysfunction has been identified in patients following traumatic brain injury (TBI), including concussion. Abnormal postural heart rate and blood pressure instability have been identified in post-concussive patients. Recently, we have identified abnormal respiratory patterns during autonomic testing for post-concussive symptoms. Tachypnea is a clinical feature of autonomic instability in paroxysmal sympathetic hyperactivity following severe TBI and the purpose of this study is to identify abnormal respiratory patterns in patients with autonomic nervous system impairment following mild TBI.

Methods

A retrospective review of patients in the Mayo Clinic Arizona Concussion Program from October 2017 to March of 2018 was performed. Clinical features and autonomic testing were reviewed. Autonomic testing included blood pressure and heart rate responses to Valsalva, heart rate variability during deep breathing, blood pressure and heart rate responses to head-up tilt, sudomotor testing, and respiratory responses using respiratory inductive plethysmography. Patients with co-morbidities or medications with potential to influence autonomic testing were excluded.

Results

Fifteen patients with a history of concussion were studied. Nine of 15 patients had abnormal cardiovascular responses on autonomic testing, typically excessive postural tachycardia with head-up tilt. Abnormal respiratory patterns were identified in 8 of 9 patients with abnormal autonomic testing and in 3 of 6 patients without other abnormalities on autonomic testing. A number of different respiratory patterns were identified including tachypnea, prolonged apneic episodes, Cheyne-Stokes, and other unusual respiratory patterns.

Conclusion

We have identified abnormal respiratory patterns in a series of concussion patients with or without other signs of dysautonomia. Tachypnea has been previously reported as a clinical feature of paroxysmal sympathetic hyperactivity following severe TBI and was present in some patients in this series. The clinical significance and mechanisms involved in the generation of respiratory dysrhythmia require further study, but may be another manifestation of post-concussive dysautonomia.

Nonconvulsive status epilepticus secondary to acute porphyria crisis

Both variegate and acute intermittent porphyria can manifest with various neurological symptoms. Although acute symptomatic seizures have been previously described, they are typically tonic–clonic and focal impaired awareness seizures. Convulsive status epilepticus and epilepsia partialis continua are rare and have been described on a case report basis. To our knowledge, there are no previously reported cases describing non-convulsive status epilepticus (NCSE) with electroencephalogram (EEG) documentation in the setting of acute porphyria crisis. We report a unique presentation of NCSE, which resolved after administering levetiracetam in a patient with variegate porphyria, without a known seizure disorder.

•

Seizures among acute intermittent porphyria (AIP) patients are not uncommon with prevalence being as high as 10%–20%.

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Non-convulsive status epilepticus (NCSE) in variegate porphyria (VP) patients should be considered in patients with altered mental status and acute porphyric crisis.

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Recognition and avoidance of prophyrogenic anti-seizure medications is important in the treatment of these patients.

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Levetiracetam and hemin are potential treatment combinations for nonconvulsive status epilepticus in acute porphyria crisis patients.

Disorders of the Cauda Equina

PURPOSE OF REVIEW

Conditions that affect the cauda equina are a diverse group of disorders that require timely recognition and management. This article reviews cauda equina anatomy, the diagnostic approach to disorders of the cauda equina, features of cauda equina syndrome, and diskogenic and nondiskogenic disorders of the cauda equina.

RECENT FINDINGS

Establishing clinical criteria for cauda equina syndrome has been a focus of a number of reviews, although the clinician must maintain a low threshold for emergent imaging in cases of suspected cauda equina syndrome because of the suboptimal reliability of various signs and symptoms in identifying this condition clinically. The timing of surgical intervention for compressive causes of cauda equina dysfunction remains a point of contention, although urgent decompression remains standard practice. A recent review that focused on outcomes in patients with cauda equina compression who underwent surgical decompression identified significant residual deficits in patients despite appropriate and timely intervention. Autoimmune conditions targeting the cauda equina have been increasingly recognized, including chronic immune sensory polyradiculopathy and chronic immune sensorimotor polyradiculopathy.

SUMMARY

Disorders that affect the cauda equina require thoughtful and timely clinical examination and diagnostic testing to establish a definitive cause and an appropriate treatment approach.

Compound muscle action potential duration in critical illness neuromyopathy

INTRODUCTION

We sought to determine the specificity of compound muscle action potential (CMAP) durations and amplitudes in a large critical illness neuromyopathy (CINM) cohort relative to controls with other neuromuscular conditions.

METHODS

Fifty-eight patients with CINM who had been seen over a 17-year period were retrospectively studied. Electrodiagnostic findings of the CINM cohort were compared with patients with axonal peripheral neuropathy and myopathy due to other causes.

RESULTS

Mean CMAP durations were prolonged, and mean CMAP amplitudes were severely reduced both proximally and distally in all nerves studied in the CINM cohort relative to the control groups. The specificity of prolonged CMAP durations for CINM approached 100% if they were encountered in more than 1 nerve.

DISCUSSION

Prolonged, low-amplitude CMAPs occur more frequently and with greater severity in CINM patients than in neuromuscular controls with myopathy and axonal neuropathy and are highly specific for the diagnosis of CINM. Muscle Nerve 57: 395-400, 2018.

Metabolic and toxic causes of myelopathy

PURPOSE OF REVIEW

This article provides an update on the various metabolic and toxic causes of myelopathy. The clinical features, laboratory findings, characteristic imaging and electrodiagnostic patterns, and approach to treatment are reviewed in depth.

RECENT FINDINGS

Vitamin B12 deficiency is a common condition, with prevalence rates that increase with age, and is particularly common in the elderly and in certain geographic areas. Nutritional surveys from the United States have suggested prevalence rates of approximately 6% in those 70 years of age or older, and prevalence rates were reported to be 10% in those older than 75 in the United Kingdom. Copper deficiency is a less common cause of myelopathy, but may result in clinical signs and symptoms indistinguishable from those of vitamin B12 deficiency. Recent reports highlight the importance of excessive zinc in the pathogenesis of copper deficiency and the importance of exogenous zinc cessation in the treatment of copper deficiency. A recent study reviewed previously reported cases of zinc myelopathy in zinc-smelter workers in the 1870s. These workers developed symptoms identical to those reported in the modern descriptive series of copper deficiency myeloneuropathy.

SUMMARY

Deficiencies of vitamin B12, folate, copper, and vitamin E may result in characteristic clinical, electrodiagnostic, and imaging features. Prompt recognition and treatment is critical to limit permanent neurologic impairment. Recognition of the toxic causes of myelopathy, including nitrous oxide exposure, heroin, radiation, various chemotherapeutic agents, liver disease, konzo, lathyrism, and zinc excess, is aided by understanding the typical clinical and imaging features associated with these agents.

Diagnostic approach to myeloneuropathy

Disorders that concomitantly affect the spinal cord and peripheral nerves can be characterized as myeloneuropathies. Such conditions can be broadly categorized as metabolic, inflammatory, infectious, or hereditary disorders. Because these disorders may present with predominantly myelopathic or peripheral neuropathic signs and symptoms, a careful neurologic examination and a thoughtful diagnostic evaluation are necessary to establish a diagnosis of myeloneuropathy. This article outlines an approach to the identification, evaluation, and treatment of myeloneuropathy.

Late-onset axial myopathy and camptocormia in a calpainopathy carrier

Camptocormia is a debilitating gait disorder characterized by the hyperflexion of the thoracolumbar spine during the upright position. Its etiologies are heterogenous, including parkinsonism and various neuromuscular disorders. Here, we report a camptocormia patient due to a late-onset axial myopathy with numerous lobulated fibers. The patient's father reportedly had similar symptoms. Myriad lobulated fibers are common among patients with an autosomal recessive muscular dystrophy due to calpain-3 gene (CAPN3) mutations or calpainopathy. CAPN3 sequencing revealed a single c.759-761delGAA mutation. Calpainopathy carriers are generally asymptomatic. The presence of lobulated fibers in this patient suggests that camptocormia could be a manifestation of calpainopathy carrier, although the possibility of a coexisting undiagnosed myopathy cannot be excluded. The current patient should spur the evaluation of camptocormia among calpainopathy carriers.

Superficial siderosis mimicking amyotrophic lateral sclerosis

We report a case of superficial siderosis erroneously diagnosed as amyotrophic lateral sclerosis. The patient's symptoms began 18 years prior with unilateral upper extremity weakness, fasciculations, and hyperreflexia. The patient then developed ataxia and hearing loss 15 years after his original symptoms. The magnetic resonance images revealed superficial siderosis involving the spinal cord and brain. We want to attract attention to superficial siderosis as a rare amyotrophic lateral sclerosis mimic disorder.

Clinical and electrodiagnostic findings in copper deficiency myeloneuropathy

INTRODUCTION

Copper deficiency is an increasingly recognised cause of neurological impairment. This retrospective review highlights clinical and electrodiagnostic findings in patients diagnosed at our institution with copper deficiency.

METHODS

Clinical, radiographic and electrodiagnostic findings were reviewed in patients with evidence of copper deficiency. Patients with other potential causes of myelopathy or neuropathy were excluded.

RESULTS

The predominant clinical feature in all six patients was a sensory ataxia, resulting in marked gait unsteadiness. Nerve conduction studies and needle EMG were performed in all patients and revealed a mild to moderate distal, axonal, sensorimotor peripheral neuropathy. Median and tibial somatosensory evoked potentials were abnormal in all five patients in which it was performed, showing impaired conduction in central or proximal peripheral somatosensory pathways.

CONCLUSIONS

This pattern of electrodiagnostic findings suggests that impairment in somatosensory pathways demonstrated by somatosensory evoked potential testing is the main cause of the sensory ataxia in patients with copper deficiency.

Approach to the Evaluation of Small Fiber Peripheral Neuropathy and Disorders of Orthostatic Intolerance

Small fiber peripheral neuropathy is a frequently encountered neurological disorder, which can be difficult to diagnose. In this article, the differential diagnosis of small fiber neuropathy is discussed, along with role of autonomic testing, skin biopsy, and quantitative sensory testing, in establishing a definitive diagnosis of small fiber peripheral neuropathy. Disorders of orthostatic intolerance, including postural orthostatic tachycardia syndrome (POTS), are also discussed, emphasizing diagnostic evaluation and a treatment approach to these disorders.

Copper deficiency myeloneuropathy resembling B12 deficiency: partial resolution of MR imaging findings with copper supplementation

Copper deficiency has been associated with a clinical syndrome, myeloneuropathy. Radiographic changes resembling B(12) deficiency in the cervical spinal cord have been described. We present a case of copper deficiency myeloneuropathy, with cervical MR imaging findings resembling B(12) deficiency, which partially reversed following copper supplementation. This is, to our knowledge, the first described case of radiographic improvement with copper supplementation.

Successful brainstem cavernous malformation resection after repeated hemorrhages during pregnancy

BACKGROUND

Pregnancy may be a risk factor for aggressive behavior in cavernous malformations. Relatively few cases exist in the literature and management is unclear.

METHODS

This unique case report describes a 28-year-old female 27 weeks pregnant who presented with 2 hemorrhages from a pontine cavernous malformation within 1 week. Morbidity increased with the second hemorrhage.

RESULTS

The patient underwent a suboccipital craniotomy and excision of the cavernous malformation. She successfully delivered a normal child at 36 weeks gestation and is ambulatory and independent 3 months postoperatively.

CONCLUSIONS

Pregnancy and prior hemorrhage may be risk factors for repeated hemorrhages. Management decisions can be difficult during pregnancy, but successful excision during pregnancy is possible. The behavior of cavernous malformations and management decisions for this patient are discussed.

Ondansetron-induced multifocal encephalopathy

We treated a patient who developed transient multifocal encephalopathy with extrapyramidal symptoms (oromandibular dystonia, oculogyric crisis, and limb dystonia) in temporal proximity to ondansetron administration on emergence from general anesthesia. No other medications known to cause extrapyramidal reactions were administered. Although these symptoms resolved fully, the presentation was dramatic and resembled the symptoms of structural brain injury. Ondansetron is used frequently as an antiemetic agent in many clinical settings and is not limited to surgical patients. Therefore, the entire medical community should be cognizant of this potential adverse reaction.

The effect of oxygen tension on the growth and metabolism of WI-38 cells

The effect of oxygen tension on cellular growth and metabolism was studied in actively growing WI-38 cells [greater than 90% labeled nuclei (LN)] grown under atmospheres containing 5% CO2 and various combinations of O2 and N2. Cells grown under a partial pressure of oxygen (PO2) of 7.8 +/- 3.5 mm Hg had a significantly slower growth rate, lower saturation densities and higher rates of glucose consumption and lactate production than did cells grown under a PO2 of 44 +/- 7 mm Hg. There were no significant differences in saturation density or the rates of glucose consumption or lactate production between cells grown under PO2 26 +/- 4 mm Hg, 44 +/- 7 mm Hg, or 134 +/- 11 mm Hg. Population doubling time was slightly prolonged at a PO2 of 134 mm Hg compared to a PO2 of 44 mm Hg. Cells grown under a PO2 of 291 +/- 25 mm Hg showed only 20-30% of the growth rate and 10-20% of the saturation density of cells grown under a PO2 of 134 mm Hg. Despite this reduced growth, cells grown under a PO2 of 291 mm Hg consumed four to six times as much glucose and produced four to six times as much lactate per cell as cells grown at a PO2 of 134 mm Hg. Cells grown under a PO2 of 560 +/- 38 mm Hg attached but did not proliferate. This toxic effect of oxygen on cell proliferation was reversible and was not due to an effect of oxygen on the media.