Recognizing Debilitating and Fatal Dysautonomia in Patients With Parkinson's Disease in the Emergency Room: A Case Report and Narrative Review.

Dysautonomia impacts multiple systems leading to a spectrum of severe disorders independent of the motor symptoms in Parkinson's disease (PD). Although the motor symptoms of dyskinesia and immobility in patients with PD were traditionally considered the major reasons leading to emergency visits, the significance of non-motor symptoms, particularly dysautonomia-related disorders, have been increasingly appreciated during their emergent encounters. We present the case of an elderly patient with advanced PD who was hit by a full spectrum of dysautonomia-related disorders, had frequent emergency visits and hospital admissions over one year, and eventually died on his fifth emergency visit. His dysautonomia-related disorders included dysphagia, gastroesophageal reflux disease, neurogenic bladder, chronic constipation, and cardiac dysautonomia with orthostatic intolerance. We further review emergent presentations, assessments, and immediate management of these dysautonomia-associated disorders in patients with PD. In summary, these dysautonomia-linked comorbidities can be debilitating and sometimes fatal. As for our case, the patient was on a clinical decline majorly due to dysautonomia and nearing the end of life over the past year. A holistic approach of possible de-escalating care and palliative care might lead to a better quality of life for the patients and their families. Nevertheless, generally speaking, emergent presentations of dysautonomia symptoms in patients with PD should be recognized and treated timely and appropriately in the emergency room. Emergency clinicians need to increase awareness and make efforts to manage these acute worsening episodes of dysautonomia disorders in patients with PD to prevent debilitating and fatal complications.

Orthostatic Intolerance in Children With Long COVID Utilizing a 10-Minute Passive Standing Test.

Despite there being a wide variety of symptoms reported in pediatric long COVID, one condition that has become increasingly recognized is orthostatic intolerance (OI), which can cause significant morbidity, limiting activities of daily living. This study examines rates of OI in 92 children with long COVID who underwent a bedside passive standing test in a pediatric post-COVID-19 rehabilitation clinic. Seventy-one percent met criteria for an orthostatic condition, including postural orthostatic tachycardia syndrome (POTS), orthostatic tachycardia (OT), classic orthostatic hypotension (OH), delayed OH, and orthostatic hypertension. Our findings suggest that OI is common in pediatric long COVID, necessitating appropriate clinical screening and treatment.

Clinical-epidemiological characterization of patients with long COVID in Mexico.

BACKGROUND: Long COVID is defined as the persistence of COVID-19 symptoms four weeks after having undergone acute infection, according to the most recent CDC definition. It is estimated that there are 65 million people affected by this entity, although other figures speak of 200 million. OBJECTIVE: To characterize the population affected by long COVID in Mexico. MATERIAL AND METHODS: Patients older than 18 years who agreed to answer an online survey and who met the criteria for long COVID were included. RESULTS: Data from 203 subjects were included, with 138 (68.0%) being found to be females, and average age to be 41.8 years; 29.6% had severe disease, and 70.4%, mild to moderate disease; 89.7% had received prior COVID-19 vaccination: 6.9% had received one dose; 31.5%, two doses; and 51.2%, three or more doses. The main risk factors were diabetes, overweight or obesity, and hypertension. The most commonly reported symptom was fatigue, followed by other neuropsychiatric manifestations. CONCLUSION: It is important for the population affected by long COVID to be characterized in order to generate diagnostic and treatment protocols.

ANTECEDENTES: El COVID persistente se define como la persistencia de síntomas de COVID-19 después de cuatro semanas de cursar con un cuadro agudo, según la definición más reciente de los Centers for Disease Control and Prevention. Se estima que existen 65 millones de personas afectadas por esta entidad, aunque algunos reportes indican 200 millones. OBJETIVO: Caracterizar a la población afectada por COVID persistente en México. MATERIAL Y MÉTODOS: Se incluyeron pacientes mayores de 18 años que consintieron responder a una encuesta en línea y que cumplían los criterios de COVID persistente. RESULTADOS: Se incluyeron los datos de 203 sujetos. Se identificó que 138 (68.0 %) contestaron ser del sexo femenino, con una media de edad de 41.8 años; 29.6 % presentó enfermedad grave y 70.4 %, enfermedad leve a moderada; 89.7 % había recibido vacunas previas para COVID-19: 6.9 %, una dosis; 31.5 %, dos dosis; y 51.2 %, tres o más dosis. Los principales factores de riesgo fueron diabetes, sobrepeso u obesidad e hipertensión arterial sistémica. El principal síntoma reportado fue fatiga, seguido de otras manifestaciones neuropsiquiátricas. CONCLUSIÓN: Es importante caracterizar a la población para generar protocolos de diagnóstico y tratamiento.

Elevated total serum IgM predicts the presence of antiphospholipid antibodies in dysautonomia patients.

Dysautonomia is an abnormal clinical state with multiple etiologies, including autoimmunity. Antiphospholipid antibodies (aPL) are among the autoantibodies that have been associated with autonomic dysfunction. We have observed that an elevated total serum IgM appears to be associated with the presence of aPL in dysautonomia patients. This is a retrospective study analyzing the clinical characteristics of 45 consecutive patients with cardiac autonomic dysfunction and a persistently elevated total serum IgM. 93% of patients were female with a mean age of 32.7 years. Most patients had severely disabling disease, with a mean Karnofsky-like functional ability score of 42% (normal 100%). 93% of patients tested persistently positive for one or more aPL and all patients tested persistently positive for aPL and/or Sjogren's antibodies. No patient had lupus specific antibodies. One third of patients experienced one or more thrombotic events and 58% of patients attempting pregnancy experienced pregnancy morbidity. Lastly, 78% of aPL-positive patients treated with antithrombotic therapy experienced 50 to 100% improvement in one or more symptoms (e.g., migraine, cognitive dysfunction) recognized to be responsive to antithrombotic therapy in a subset of aPL-positive patients and 73% of patients treated with and tolerating immune modulatory therapy experienced a positive response. We propose total serum IgM as a reliable and inexpensive test that can be used to identify dysautonomia patients at risk for persistent aPL-positivity. These patients are important to identify as they have a significant risk for thrombosis and pregnancy morbidity and often experience significant symptomatic improvement with antithrombotic therapy and/or immune modulatory therapy.

CURRENT CONCEPTS IN LONG-COVID BRAIN FOG AND POSTURAL ORTHOSTATIC TACHYCARDIA SYNDROME.

Neurologic complications of long-COVID syndrome are one of the leading causes of global disability. In particular, post-COVID cognitive dysfunction and dysautonomia in the form of postural orthostatic tachycardia syndrome (POTS) markedly affect patient quality of life and ability to return to work. The underlying pathophysiology of postCOVID neurologic complications is unknown but is likely multifactorial with immune dysregulation and microvascular dysfunction playing central roles. Specific pathogenic factors with supportive evidence to date include cytokine-mediated inflammation, autoantibodies, immune exhaustion, disruption of the renin-angiotensin system, reduced serotonin levels and microglial activation. The prevalence of post-COVID cognitive dysfunction ranges from 10% to 88% and is affected by viral variant and hospitalization status among other factors, while that of long-COVID POTS is unknown due to referral bias and varying definitions. Treatment is largely supportive and often incorporates combined modalities. Marginal benefits with cognitive behavioral therapy, hyperbaric oxygen therapy and supplements have been shown for post-COVID brain fog, while established POTS therapies aimed at improving venous return and reducing heart rate may reduce symptoms of long-COVID POTS. Although significant recovery has been noted for many cases of post-COVID brain fog and POTS, prospective studies have demonstrated evidence of persistent symptoms and neurologic deficits a year after infection in some patients. Further studies that provide insight into the underlying pathophysiology of long-COVID are needed for development of target directed therapy.

Cardiopulmonary exercise testing in long covid shows the presence of dysautonomia or chronotropic incompetence independent of subjective exercise intolerance and fatigue.

BACKGROUND: After COVID-19 infection, 10-20% of patients suffer from varying symptoms lasting more than 12 weeks (Long COVID, LC). Exercise intolerance and fatigue are common in LC. The aim was to measure the maximal exercise capacity of the LC patients with these symptoms and to analyze whether this capacity was related to heart rate (HR) responses at rest and during exercise and recovery, to find out possible sympathetic overactivity, dysautonomia or chronotropic incompetence. METHODS: Cardiopulmonary exercise test was conducted on 101 LC patients, who were admitted to exercise testing. The majority of them (86%) had been treated at home during their acute COVID-19 infection. Peak oxygen uptake (VO2peak), maximal power during the last 4 min of exercise (Wlast4), HRs, and other exercise test variables were compared between those with or without subjective exercise intolerance, fatigue, or both. RESULTS: The measurements were performed in mean 12.7 months (SD 5.75) after COVID-19 infection in patients with exercise intolerance (group EI, 19 patients), fatigue (group F, 31 patients), their combination (group EI + F, 37 patients), or neither (group N, 14 patients). Exercise capacity was, in the mean, normal in all symptom groups and did not significantly differ among them. HRs were higher in group EI + F than in group N at maximum exercise (169/min vs. 158/min, p = 0.034) and 10 min after exercise (104/min vs. 87/min, p = 0.028). Independent of symptoms, 12 patients filled the criteria of dysautonomia associated with slightly decreased Wlast4 (73% vs. 91% of sex, age, height, and weight-based reference values p = 0.017) and 13 filled the criteria of chronotropic incompetence with the lowest Wlast4 (63% vs. 93%, p < 0.001), VO2peak (70% vs. 94%, p < 0.001), the lowest increase of systolic blood pressure (50 mmHg vs. 67 mmHg, p = 0.001), and the greatest prevalence of slight ECG-findings (p = 0.017) compared to patients without these features. The highest prevalence of chronotropic incompetence was seen in the group N (p = 0.022). CONCLUSIONS: This study on LC patients with different symptoms showed that cardiopulmonary exercise capacity was in mean normal, with increased sympathetic activity in most patients. However, we identified subgroups with dysautonomia or chronotropic incompetence with a lowered exercise capacity as measured by Wlast4 or VO2peak. Subjective exercise intolerance and fatigue poorly foresaw the level of exercise capacity. The results could be used to plan the rehabilitation from LC and for selection of the patients suitable for it.

Suspected Diphtheria Toxoid and Tetanus Toxoid (dTdap) Booster Vaccine-Induced Postural Orthostatic Tachycardia Syndrome (POTS).

We describe a case of a 40-year-old South Asian woman who presented with symptoms suggestive of postural orthostatic tachycardia syndrome (POTS) following a diphtheria toxoid and tetanus toxoid (dTdap) booster vaccination administered one week prior. The patient's POTS responded favorably to treatment with low-dose fludrocortisone and ivabradine. Clinicians should maintain a high index of suspicion for POTS as a possible vaccine adverse event (VAE) post-dTdap booster inoculation and be aware of appropriate management strategies.

Lipofuscin accumulates in ganglionic neurons in chronic equine dysautonomia.

Lipofuscin is a complex mixture of highly oxidized, cross-linked macromolecules that accumulates in neurons with age and some neurodegenerative diseases. Equine dysautonomia (ED) is a polyneuropathy that mainly affects autonomic and enteric nervous systems, resulting in alimentary tract dysfunction. Our main aim was to determine whether neuronal lipofuscin increased with increasing duration of ED. We investigated the prevalence of lipofuscin in cranial cervical ganglia of horses with acute (AED), subacute (SED), and chronic ED (CED), young controls (of similar age to ED cases), and aged controls (n = 8 per group). We used Schmorl stain for histologic detection of lipofuscin and assessed its accumulation in neurons using image analysis software. The percentage of neurons positive for lipofuscin increased with age in individual groups and all groups combined (p < 0.001). There were fewer positive neurons in AED and SED compared to aged controls (p < 0.001) and more in CED than AED cases (p = 0.042) and young controls (p = 0.012). We found a strong positive correlation between percentage positive neurons and percentage positive area of the neuron containing lipofuscin for combined groups (p < 0.001). Although neuronal lipofuscin increased in cranial cervical ganglion in CED cases, it remains to be determined whether this is a cause or consequence of neuronal degeneration.

Evaluation of low vagally-mediated heart rate variability as an early marker of depression risk.

BACKGROUND: Both low vagally-mediated heart rate variability (HRV) and depression have been shown to be risk factors for cardiovascular disease (CVD). We recently identified an HRV cutpoint below which persons have an increased risk for several cardiometabolic disorders. However, no cutpoint exists to identify those at risk for depression. METHODS: The association between daytime HRV and diagnostically validated depression cutoffs using the five-item World Health Organization Well-being Index (WHO-5) was examined in adults from the Mannheim Industrial Cohort Study (n = 9973; Mage = 41.9[10.9]; 20 % women [n = 1934]). The aim was to identify HRV cutpoints for individuals who may have clinical depression. RESULTS: Regression adjusting for age, sex, and linear trend showed a significant quadratic association between depression, indexed by WHO-5 scores and HRV, indexed by the root mean square successive differences (RMSSD) in milliseconds (ms) (p < 0.001). Logistic regression models adjusting for age, sex, and heart period (i.e., inter-beat intervals) compared the clinically depressed (WHO-5 ≤ 28) and those with a screening diagnosis of depression (WHO-5 ≤ 50) to the rest of the population. Significant odds ratios suggested two RMSSD values 25 ± 2 ms (OR = 1.39 [1.17, 1.64]) and 35 ± 2 ms (OR = 1.17 [1.02, 1.34]) that may be used to identify those with an elevated risk for depression. LIMITATIONS: The sample was primarily German men. Fitness and anti-depressant use were not available. CONCLUSIONS: As HRV is a brief measure that can be used in clinical settings, our HRV cutpoints have implications for the early detection of those at risk for psychological and cardiometabolic disorders.

Role of prazosin in patients with Guillain-Barré syndrome with sympathetic overactivity: A cohort study.

INTRODUCTION/AIMS: In Guillain-Barré syndrome (GBS), patients with dysautonomia demonstrate sympathetic overactivity (SO). This study assessed the role of prazosin (α1-blocker) in the management of SO. METHODS: This cohort study was conducted from January 2022 to September 2023. Thirty-two GBS patients with SO received prazosin (2.5-10 mg three times a day) (prazosin group). For comparison, we included historical controls that included 33 GBS patients having SO with similar baseline characteristics, including median age and disability, who did not receive prazosin, from a GBS registry of patients admitted during February 2018-December 2021. The primary endpoint was days to resolution of SO. Secondary endpoints were daily fluctuations in the systolic (SBP) and diastolic blood pressure (DBP), duration of hospital stay, in-hospital mortality, and disability at 3 months. RESULTS: The median ages of both the treatment and the control groups were 36 (IQR 25-49) years and 43 (66.2%) were males. The demographic and clinical parameters were comparable. Prazosin resulted in significantly earlier normalization of SO compared to the control group (median 15 vs. 20 days; p = .01). The mean fluctuations in the SBP and DBP at 15 days were significantly lower in the prazosin group. However, the duration of hospital stay and good recovery at 3 months were comparable. Three patients developed hypotension, while two patients died (ventilator-associated pneumonia) in the prazosin group. DISCUSSION: This study provides new evidence supporting the role of prazosin in SO, and needs randomized trials to confirm our findings.

Loss of Elp1 in cerebellar granule cell progenitors models ataxia phenotype of Familial Dysautonomia.

Familial Dysautonomia (FD) is an autosomal recessive disorder caused by a splice site mutation in the gene ELP1, which disproportionally affects neurons. While classically characterized by deficits in sensory and autonomic neurons, neuronal defects in the central nervous system have also been described. Although ELP1 expression remains high in the normal developing and adult cerebellum, its role in cerebellar development is unknown. To explore the role of Elp1 in the cerebellum, we knocked out Elp1 in cerebellar granule cell progenitors (GCPs) and examined the outcome on animal behavior and cellular composition. We found that GCP-specific conditional knockout of Elp1 (Elp1cKO) resulted in ataxia by 8 weeks of age. Cellular characterization showed that the animals had smaller cerebella with fewer granule cells. This defect was already apparent as early as 7 days after birth, when Elp1cKO animals also had fewer mitotic GCPs and shorter Purkinje dendrites. Through molecular characterization, we found that loss of Elp1 was associated with an increase in apoptotic cell death and cell stress pathways in GCPs. Our study demonstrates the importance of ELP1 in the developing cerebellum, and suggests that loss of Elp1 in the GC lineage may also play a role in the progressive ataxia phenotypes of FD patients.

Children and Young Adults with Epilepsy Exhibit an Interictal Autonomic Dysfunction: A Prospective Exploratory Study.

Dysautonomic disorders are an increasingly studied group of conditions, either as isolated diseases or associated with other neurological disorders. There is growing interest in understanding how dysautonomia affects people with epilepsy, who may report autonomic symptoms before, during and after seizures. Furthermore, autonomic abnormalities appear to play a role in sudden unexpected death in epilepsy, likely contributing to the increased mortality rate described in epilepsy. To better understand the association between epilepsy and dysautonomia, we explored electrochemical skin conductance in a group of 18 children and young adults with epilepsy compared to 15 age- and sex-matched healthy controls by the SudoscanTM test. We found a significant difference in terms of electrochemical skin conductance, suggesting that people with epilepsy suffer significantly reduced conductance in small nerve fibers. Within patients, values were significantly different according to the type of epilepsy and to neuroimaging results, with lower conductance values in epilepsies of unknown origin and in patients with morphological abnormalities of the brain. Using a non-invasive test, we identified altered conductance of small sympathetic nerve fibers in children and young adults with epilepsy, suggesting underlying dysautonomia. Further studies are needed to investigate this association and to clarify its neurobiological substrates.

Long-Term POTS Outcomes Survey: Diagnosis, Therapy, and Clinical Outcomes.

BACKGROUND: Limited data exist on long-term outcomes in individuals with postural orthostatic tachycardia syndrome (POTS). We designed an electronic questionnaire assessing various aspects of outcomes among patients diagnosed and treated in a single-center pediatric POTS clinical program. METHODS AND RESULTS: The LT-POTS (Long Term POTS Outcomes Survey) included questions about quality of life, symptoms, therapies, education, employment, and social impact of disease. Patients age≤18 years at POTS diagnosis who were managed in the Children's Hospital of Philadelphia POTS Program were included. A total of 227 patients with POTS responded with sufficient data for interpretation. The mean age of respondents was 21.8±3.5 years. The median age of symptom onset was 13 (interquartile range 11-14) years, with mean 9.6±3.4 years symptom duration. Multiple cardiovascular, neurologic, and gastrointestinal symptoms were reported. Symptom prevalence and severity were worse for female patients, with 99% of patients reporting ongoing symptoms. Quality of life showed moderate function and limitation, with more severe limitations in energy/fatigue and general health. Nearly three quarters of patients had diagnostic delays, and over half were told that their symptoms were "in their head." Multiple medications were used and were felt to be effective, whereas fewer nonpharmacologic interventions demonstrated efficacy. Nearly 90% of patients required continued nonpharmacologic therapy to control symptoms. CONCLUSIONS: POTS is a chronic disorder leading to significant disability with a range of multisystem problems. Although symptoms can be modifiable, it rarely spontaneously resolves. Improved understanding of POTS presentation and therapeutic approaches may inform provider education, improve diagnostic success, and help patients self-advocate for appropriate medical management approaches.

Moderately intense physical exercise alleviates electrocardiographic changes induced by cisplatin in rats.

INTRODUCTION AND OBJECTIVE: Cisplatin induces many collateral effects such as gastrointestinal disorders, nephrotoxicity, and dysautonomia. Recently our group showed that cisplatin treatment induces gastric emptying delay and that physical exercise and treatment with pyridostigmine prevent this change. In the current study, we investigated the role of moderate exercise on cardiac activity and autonomic balance in rats treated with cisplatin. METHODS: Male Wistar rats were divided into saline, cisplatin, exercise, and exercise+cisplatin groups. Cardiac and autonomic disorders were induced by (cisplatin - 3 mg/kg, i.p. once a week/per 5 weeks). Exercise consists of swimming (1 hour per day/5× day per week/per 5 weeks without overload). Forty-eight hours after the last session of the training or treatment, we assessed the cardiac activity and HRV via electrocardiogram analysis in DII derivation. RESULTS: Cisplatin increase (p<0.05) R-R' interval and decrease (p<0.05) heart rate vs. saline. Exercise+cisplatin prevented (p<0.05) changes in R-R' interval. Exercise per se induced bradycardia vs. saline group. We observed an increase in LF (nu) and a decrease in HF (nu) in the cisplatin group vs. saline. These changes were not significant. Moreover, cisplatin treatment increased (p<0.05) QT, QTc, and JT intervals compared with the saline group. In the exercise+cisplatin groups these increases were prevented significantly (p<0.05). CONCLUSION: In the current study, chronic use of cisplatin induced electrocardiographic changes without altering autonomic balance. Moderate physical exercise prevented this phenomenon indicating that exercise can be beneficial in patients in chemotherapy.

Acceleration index predicts efficacy of orthostatic training on postural orthostatic tachycardia syndrome in children.

The objective of this study was to examine the utility of the acceleration index observed in an electrocardiogram (ECG) for the prediction of the effectiveness of orthostatic training in pediatric patients diagnosed with postural orthostatic tachycardia syndrome (POTS). This investigation focused on children diagnosed with POTS and undergoing orthostatic training at the Department of Pediatrics of Peking University First Hospital from January 2012 to October 2022. Specifically, patients hospitalized from January 2012 to December 2019 were included in the training set (54 cases), while those hospitalized from January 2020 to October 2022 were included in the external validation set (37 cases). All children received a 3-month orthostatic training, and the baseline symptom score (SS) was calculated in agreement with the pretreatment orthostatic intolerance symptom frequency. Additionally, we determined post-treatment SS during follow-up via telephone after the 3-month treatment. Children with a decrease in post-treatment SS by ≥ 50% of the baseline were considered as responders; otherwise, they were considered as non-responders. Demographic data (age, sex, and body mass index), hemodynamic parameters (supine blood pressure, time to achieve a positive standing test, maximum increase in heart rate during the standing test, maximal heart rate reached during the standing test, and blood pressure at the point of maximal heart rate during the standing test), and electrocardiographic parameters (RR interval in the supine position, shortest RR interval in the upright position, and acceleration index) were collected from all the children prior to treatment. Univariate and multivariate regression analysis were conducted to investigate factors associated with the efficacy of orthostatic training. The predictive value of these indicators for the therapeutic effectiveness of orthostatic training in children with POTS was evaluated using receiver operating characteristic (ROC) analysis, and the indicators were validated using the validation set. Among the 54 children in the training set, 28 responded to orthostatic training, and 26 were nonresponsive. Compared with the non-responders, the responders demonstrated a significant reduction in acceleration index (P < 0.01). The ROC curve for the predictive value of the acceleration index exhibited an area under the curve = 0.81 (95% confidence interval: 0.685-0.926). With the acceleration index threshold < 27.93%, the sensitivity and specificity in the prediction of orthostatic training efficacy among children with POTS were 85.7% and 69.2%, respectively. The external validation results demonstrated that using acceleration index < 27.93% as the threshold, the sensitivity, specificity, and accuracy of predicting orthostatic training efficacy among children with POTS were 89.5%, 77.8%, and 83.8%, respectively. CONCLUSIONS: Electrocardiographic acceleration index can be used to predict the effectiveness of orthostatic training in treating children with POTS. WHAT IS KNOWN: • Postural orthostatic tachycardia syndrome (POTS) is a chronic orthostatic intolerance involving multiple mechanisms. Autonomic dysfunction is one of the main mechanisms of POTS in children and could be treated with orthostatic training. • In order to improve the efficacy of orthostatic training in children with POTS, it is particularly important to identify the patients with autonomic dysfunction as the main mechanism before the treatment. WHAT IS NEW: • We found acceleration index of the electrocardiogram (ECG) can be used as a satisfactory index to predict the efficacy of orthostatic training in the treatment of POTS in children. • Using the acceleration index to predict the efficacy of orthostatic training on POTS in children is easy to be popularized in hospitals at all levels because it is non-invasive, convenient, and not expensive.

Invalidated and 'salty': an auto/biographical and theoretical review of the lived experiences of individuals with PoTS.

Postural orthostatic Tachycardia Syndrome (PoTS), sometimes also written as 'POTS', is a form of dysautonomia (dysfunction of the autonomic nervous system) and orthostatic intolerance (which causes symptoms to be worsened when standing). This paper explores the extant literature on the lived experiences of those living with PoTS in relation to interactions between patients and healthcare providers as well as interactions at the level of the individual between PoTSies and those around them. My title contains the word 'salty' because it can be used to describe the feeling of being frustrated, while also reflecting a specific dietary change recommended to many (but not all) PoTS patients when they are told to consume additional sodium to minimise symptoms. COVID-19 is thought to have led to an increased prevalence of PoTS so this topic is particularly relevant to contemporary discussions and debates. In this sociological article, I refer not only to existing research on the lived experiences of having PoTS but also that of other chronic illnesses when relevant. The following themes are explored through auto/biographical and theoretical analysis: Undiagnosed and Invalidated; (In)Visible; Impacts of Diagnosis; Recovery and Expectations; Community. Reflecting auto/biographically, I have included analysis of interactions related to my lived experiences of presyncope, COVID-19 and dysautonomia, as I have been diagnosed with PoTS myself, which is thought to have been significantly exacerbated by the COVID-19 virus. This research is sociological, rather than medical or psychological, and conclusions are drawn about what is known so far about the lived experiences of living with PoTS, as well as discussion about what remains unknown, as there is currently a paucity of research on the lived experiences of individuals with PoTS and its comorbidities.

Recurrent Fevers, Dysautonomia, and Dehydration in a Patient With Lesch-Nyhan Syndrome.

Lesch-Nyhan syndrome (LNS) is a disease characterized by a reduced ability to recycle purines, leading to increased de novo purine synthesis and uric acid production. Patients classically present with an array of hyperuricemic, neurologic, and behavioral symptoms. In this report, we describe a 26-year-old male with a history of LNS and recurrent fevers of unknown origin who presented to the emergency department (ED) with a fever, hypotension, and hypernatremia. We suspect that our patient's presentation was caused by autonomic instability in the setting of LNS leading to excessive free water loss. This report highlights a rare but life-threatening manifestation of LNS.

Predominant cardiac sympathetic modulation during wake and sleep in patients with Rett syndrome.

BACKGROUND: Rett syndrome (RTT) is a rare neurological disorder primarily associated with mutations in the methyl-CpG-binding protein 2 (MECP2) gene. The syndrome is characterized by cognitive, social, and physical impairments, as well as sleep disorders and epilepsy. Notably, dysfunction of the autonomic nervous system is a key feature of the syndrome. Although Heart Rate Variability (HRV) has been used to investigate autonomic nervous system dysfunction in RTT during wakefulness, there is still a significant lack of information regarding the same during sleep. Therefore, our aim was to investigate cardiovascular autonomic modulation during sleep in subjects with RTT compared to an age-matched healthy control group (HC). METHOD: A complete overnight polysomnographic (PSG) recording was obtained from 11 patients with Rett syndrome (all females, 10 ± 4 years old) and 11 HC (all females, 11 ± 4 years old; p = 0.48). Electrocardiogram and breathing data were extracted from PSG and divided into wake, non-REM, and REM sleep stages. Cardiac autonomic control was assessed using symbolic non-linear heart rate variability analysis. The symbolic analysis identified three patterns: 0 V% (sympathetic), 2UV%, and 2LV% (vagal). RESULTS: The 0 V% was higher in the RTT group than in the HC group during wake, non-REM, and REM stages (p < 0.01), while the 2LV and 2UV% were lower during wake and sleep stages (p < 0.01). However, the 0 V% increased similarly from the wake to the REM stage in both RTT and HC groups. CONCLUSIONS: Therefore, the sympatho-vagal balance shifted towards sympathetic predominance and vagal withdrawal during wake and sleep in RTT, although cardiac autonomic dynamics were preserved during sleep.

PRESenting a Challenge: Posterior Reversible Encephalopathy Syndrome in Pediatric Patients With Guillain-Barré Syndrome: A Case Series and Review of Literature.

BACKGROUND: Guillain-Barré syndrome (GBS) is an autoimmune disorder characterized by demyelination of peripheral nerves. GBS-associated posterior reversible encephalopathy syndrome (PRES) is a rare and potentially life-threatening complication in the pediatric population. We aimed to report and analyze the clinical features, management, and outcomes of three cases of GBS-associated PRES in our setting in the light of the existing literature. METHODS: Medical records of 75 pediatric patients with GBS were reviewed for autonomic changes and GBS-associated PRES. Thirty-one developed dysautonomia while three were identified to have PRES. Clinical, radiological, laboratory, and treatment data were collected and analyzed. RESULTS: All three patients were male and presented with symptoms of acute flaccid paralysis and respiratory distress requiring mechanical ventilation. All three patients experienced various complications, including hypertension, seizures, and hyponatremia, and were subsequently diagnosed with PRES. Multimodal intensive care resulted in patient improvement and discharge in an ambulatory state after an average of 104 days of care. CONCLUSIONS: GBS-associated PRES is a rare and potentially life-threatening complication that can occur in pediatric patients with GBS. Our findings suggest that early recognition, prompt intervention, and multimodal intensive care can improve patient outcomes. Further studies are needed to determine optimal treatment strategies for GBS-associated PRES.

Parkinson's disease with hyposmia and dysautonomia: does it represent a distinct subtype?

BACKGROUND AND PURPOSE: Olfactory dysfunction or dysautonomia is one of the earliest prodromal nonmotor symptoms of Parkinson's disease (PD). We aimed to investigate whether PD patients with dysautonomia and hyposmia at the de novo stage present different prognoses regarding PD dementia (PDD) conversion, motor complication development, and change in levodopa-equivalent doses (LED). METHODS: In this retrograde cohort study, we included 105 patients with newly diagnosed PD patients who underwent cross-cultural smell identification test (CC-SIT), autonomic function tests (AFT), and dopamine transporter (DAT) scan at the de novo stage. PD patients were divided into Hyposmia + /Dysautonomia + (H + /D +) and Hyposmia - /Dysautonomia - (H - /D -) groups depending on the result of AFT and CC-SIT. Baseline clinical, cognitive, imaging characteristics, longitudinal risks of PDD development and motor complication occurrence, and longitudinal LED changes were compared between the two groups. RESULTS: When compared with the H - /D - group, the H + /D + group showed lower standardized uptake value ratios in all subregions, lower asymmetry index, and steeper ventral - dorsal gradient in the DAT scan. The H + /D + group exhibited poorer performance in frontal/executive function and a higher risk of PDD development. The risk of motor complications including levodopa-induced dyskinesia, wearing off, and freezing of gait, was comparable between the two groups. The analysis of longitudinal changes in LED using a linear mixed model showed that the increase of LED in the H + /D + group was more rapid. CONCLUSIONS: Our results suggest that PD patients with dysautonomia and hyposmia at the de novo stage show a higher risk of PD dementia conversion and rapid progression of motor symptoms.