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Felicia B Axelrod

Publications and source records attributed to Felicia B Axelrod.

At least 19 recordsLinked to original sources

A world without pain or tears.

The world of the child with familial dysautonomia (FD), a genetic disorder affecting development of the sensory and autonomic nervous system, is not idyllic. However, over the last 35 years advances in supportive treatments have improved morbidity and mortality. Recent genetic breakthroughs have further expanded thinking about this disorder and suggested innovative approaches to modifying genetic expression. This article reviews the current supportive treatment modalities and their rationale, as well as the suggested new treatments that may alter the function and prognosis of an individual affected with FD.

Autonomic Nervous System Diseases↗

Familial dysautonomia's impact on quality of life in childhood, adolescence, and adulthood.

AIM: To evaluate the quality of life (QoL) of children, adolescents, and adults treated for familial dysautonomia (FD), a pervasive neurological disorder. METHODS: The Child Health Questionnaire was completed by parents of 71 patients, while an additional 74 patients completed the Short Form--36. RESULTS: FD imposed a greater physical than psychosocial burden on the child, while the young adults reported both mental and physical quality of life within the average range. Self-esteem was problematic and improved with age, while both groups reported lowering physical quality of life as they grew older, with worsening general health that limited their role at school or work. CONCLUSION: Younger FD patients should be closely monitored for lowered self-esteem and referred for counseling when appropriate, while physical and occupational therapy should be provided in advance of expected lowered physical QoL and role fulfillment with increasing age. This becomes important as the need for additional surgical interventions, such as fundoplication with gastrostomy or spinal fusion, contribute to lower physical functioning. Given the high degree of parental involvement required for the varied manifestations of this multisystem disorder, the need for continued parental assessment and psycho-education about this chronic medical illness is warranted.

Adolescent↗

Anesthesia management of familial dysautonomia.

Familial dysautonomia (FD) is an autosomal recessive inherited disorder, predominantly affecting the Ashkenazi Jewish population that is characterized by sensory and autonomic neuropathy. The protean manifestations and perturbations result in high morbidity and mortality. However, as a result of supportive measures and centralized care, survival has improved. As surgical options are increasing to symptomatically treat FD, anesthesiologists need to be familiar with this disorder. Because the Dysautonomia Center at NYU Medical Center is a referral center for FD patients, we have attained considerable anesthetic experience with FD. This article reviews clinical features of FD that could potentially affect anesthetic management and outlines our present practices.

Anesthesia↗

Pediatric autonomic disorders.

The scope of pediatric autonomic disorders is not well recognized. The goal of this review is to increase awareness of the expanding spectrum of pediatric autonomic disorders by providing an overview of the autonomic nervous system, including the roles of its various components and its pervasive influence, as well as its intimate relationship with sensory function. To illustrate further the breadth and complexities of autonomic dysfunction, some pediatric disorders are described, concentrating on those that present at birth or appear in early childhood.

Adrenal Insufficiency↗

Effect of physical countermaneuvers on orthostatic hypotension in familial dysautonomia.

Familial dysautonomia (FD) patients frequently experience debilitating orthostatic hypotension. Since physical countermaneuvers can increase blood pressure (BP) in other groups of patients with orthostatic hypotension, we evaluated the effectiveness of countermaneuvers in FD patients. In 17 FD patients (26.4 +/- 12.4 years, eight female), we monitored heart rate (HR), blood pressure (BP), cardiac output (CO), total peripheral resistance (TPR) and calf volume while supine, during standing and during application of four countermaneuvers: bending forward, squatting, leg crossing, and abdominal compression using an inflatable belt. Countermaneuvers were initiated after standing up,when systolic BP had fallen by 40mmHg or diastolic BP by 30mmHg or presyncope had occurred. During active standing, blood pressure and TPR decreased, calf volume increased but CO remained stable. Mean BP increased significantly during bending forward (by 20.0 (17 - 28.5) mmHg; P = 0.005) (median (25(th) - 75(th) quartile)), squatting (by 50.8 (33.5 - 56) mmHg; P = 0.002), and abdominal compression (by 5.8 (-1 - 34.7) mmHg; P = 0.04) - but not during leg-crossing. Squatting and abdominal compression also induced a significant increase in CO (by 18.1 (-1.3 - 47.9) % during squatting (P = 0.02) and by 7.6 (0.4 - 19.6) % during abdominal compression (P=0.014)). HR did not change significantly during the countermaneuvers. TPR increased significantly only during squatting (by 37.2 (11.8 - 48.2) %; P = 0.01). However, orthopedic problems or ataxia prevented several patients from performing some of the countermaneuvers. Additionally, many patients required assistance with the maneuvers. Squatting, bending forward and abdominal compression can improve orthostatic BP in FD patients, which is achieved mainly by an increased cardiac output. Squatting has the greatest effect on orthostatic blood pressure in FD patients. Suitability and effectiveness of a specific countermaneuver depends on the orthopedic or neurological complications of each FD patient and must be individually tested before a therapeutic recommendation can be given.

Adolescent↗

Pacemakers in patients with familial dysautonomia--a review of experience with 20 patients.

Familial dysautonomia (FD) is a genetic disease associated with a high incidence of sudden death. If fatal bradyarrhythmia is an etiological factor then the incidence of sudden death should decrease after pacemaker placement. Retrospective review of 596 registered FD patients revealed that 22 FD patients (3.7%) had pacemakers placed between December 1984 and June 2003. Clinical and electrocardiographic indications for placement and demographic data were assessed for 20 of the 22 patients (10 males, 10 females, ages 4 to 48 years). Two patients were excluded because of insufficient data. Prior to pacemaker placement, presenting symptoms were syncope and cardiac arrest, 16/20 (80%) and 6/20 (30 %), respectively. Asystole was the most frequent electrocardiographic finding and was documented in 17/20 patients (85 %). Other electrocardiographic abnormalities included bradycardia, AV block, prolonged QTc and prolonged JTc. The average duration of pacemaker utilization was 5.7 years (range 5 months to 14.5 years). Complications included infection (1 patient) and wire migration (2 patients). In the one patient with infection, the pacemaker was permanently removed. This patient then experienced multiple syncopal episodes and death. There were 7 other deaths. Three deaths occurred suddenly without preceding events, and 4 patients had non-cardiac causes of death. None of these 7 deceased patients had recurrence of syncope after pacemaker placement. In the 12 surviving patients, 6 had recurrence of syncope but none had cardiac arrest. Pacemaker placement may protect FD patients from fatal bradyarrhythmia and may decrease the incidence of syncope. However, data are limited and prospective analysis is needed.

Arrhythmias, Cardiac↗

Fludrocortisone in patients with familial dysautonomia--assessing effect on clinical parameters and gene expression.

The common familial dysautonomia (FD) mutation causes a splicing defect that leads to production of both wild-type (WT) and mutant (MU) IKBKAP mRNA. Because drugs may alter splicing, seven drugs, fludrocortisone, midodrine, diazepam, albuterol, clonidine, caffeine, and dopamine were screened. Since only fludrocortisone negatively altered gene expression, we assessed fludrocortisone's efficacy in treating postural hypotension, and its effect on survival and secondary long-term FD problems. For 341 FD patients we obtained demographic data and clinical information from the last Center evaluation (most current or prior to death) including mean blood pressures (supine, 1 min erect and 5 min erect) and history regarding syncope and presyncope symptoms. For 175 fludrocortisone-treated patients, data from the evaluation prior to start of fludrocortisone and from the last Center evaluation were compared. The fludrocortisone-treated patient cohort was compared to the nontreated patient cohort with respect to overall survival and event-free survival for crisis frequency, worsening gait, frequent fractures, spine curvature, renal insufficiency, and pacemaker insertion. Overall survivals of patients on fludrocortisone alone, on fludrocortisone and midodrine, and on neither drug were compared. Cumulative survival was significantly higher in fludrocortisone-treated patients than in non-treated patients during the first decade. In subsequent decades, the addition of midodrine improved cumulative survival. Fludrocortisone significantly increased mean blood pressures and decreased dizziness and leg cramping, but not headaches or syncope. Fludrocortisone was associated with more long-term problems, which may reflect more symptomatic status associated with longer survival. Our data suggest that fludrocortisone has clinical efficacy despite negative in vitro observations on gene expression.

Adolescent↗

Gastroesophageal reflux in familial dysautonomia: correlation with crisis frequency and sensory dysfunction.

OBJECTIVES: Familial dysautonomia (FD), a genetic disorder resulting in sensory and autonomic nervous system dysfunction, is associated with a high frequency of gastroesophageal reflux (GER). In this study the authors attempted to determine if GER prevalence correlated with dysautonomic crisis frequency and small fiber sensory dysfunction. METHODS: Of an initial population of 252 FD patients who had survived past their seventh year and were alive during the year of study from June 1, 2001 to June 1, 2002, 174 (69.0%) had sufficient data in their patient files to be included in this retrospective analysis. Subjects were stratified into three groups: those with no GER, those medically treated for GER and those surgically treated for GER with fundoplication. Data were obtained regarding frequency and severity of dysautonomic crises and sensory function including pain sensation, cold and warm thresholds and vibration perception. RESULTS: There were no significant differences among the three groups regarding age or severity of sensory dysfunction. However, dysautonomic crises were significantly more frequent in FD patients who were presumed to have more intractable GER, as they had required fundoplication (P < 0.05). CONCLUSIONS: The data confirm the high incidence of GER in the FD population and demonstrate that GER is independent of severity of sensory dysfunction. In addition, the authors demonstrate that fundoplication does not alleviate the central autonomic cause of retching, the dysautonomic crisis.

Adolescent↗

Assessing efficacy of high-frequency chest wall oscillation in patients with familial dysautonomia.

STUDY OBJECTIVE: To determine the benefits of daily use of high-frequency chest wall oscillation (HFCWO) in familial dysautonomia (FD) patients with lung disease. DESIGN: Pulmonary function tests, chest radiographs, and blood tests were performed on entry to the study. A retrospective chart review of 12 months prior to entry provided baseline data regarding respiratory illnesses, medications, doctor visits, hospitalizations, and absenteeism. Daily logs provided prospective data on these parameters as well as HFCWO usage. Evaluations were performed at 1, 3, 6, 9, and 12 months for pulse oximetry, spirometry, and log review. At the exit evaluation, blood tests and chest radiographs were repeated. PATIENTS: Fifteen FD patients with history of lung disease requiring daily inhalation therapy (7 female and 8 male; age range, 11 to 33 years) were enrolled in a 1-year clinical trial of HFCWO therapy. Two subjects withdrew after 3 months and 6 months, respectively. Each individual served as his/her own control. RESULTS: Oxygen saturation improved by 1 month (median, 97.5%; interquartile range [IQR], 96 to 98%; vs median, 94%; IQR, 89 to 96%) and was sustained at exit evaluation (median, 98%; IQR, 98 to 98%) [p = 0.004]. Median FVC and peak expiratory flow rate (PEFR) were the pulmonary function measures with sustained improvement from baseline to exit (p = 0.02 and p = 0.03, respectively). When retrospective and prospective data were compared, all measured health outcomes improved significantly, including pneumonias (p = 0.0156), hospitalizations (p = 0.0161), antibiotic courses (p = 0.0005), antibiotic days (p = 0.0002), doctor visits (p = 0.0005), and absenteeism (p = 0.0002). CONCLUSION: In this limited study of FD patients, HFCWO effected significant improvements in all measured health outcomes and oxygen saturation; FVC and PEFR were the pulmonary function measures demonstrating sustained improvement.

Adolescent↗

Familial dysautonomia: a review of the current pharmacological treatments.

Treatment of familial dysautonomia, a genetic disorder affecting neuronal development and survival, has improved morbidity and survival for this disorder. Although this is primarily a neurological disorder causing sensory and autonomic dysfunction, there are secondary systemic perturbations affecting ophthalmological, gastrointestinal, respiratory, cardiovascular, orthopaedic and renal function. Penetrance is complete, but there is marked variability in expression. Preventative and supportive treatments have included measures to maintain eye moisture, fundoplication with gastrostomy, the use of central agents such as benzodiazepines and clonidine to control vomiting and the dysautonomic crisis, and fludrocortisone and midodrine to combat cardiovascular lability. With the identification of the familial dysautonomia gene, it has been suggested that it may be possible to treat patients by modifying production and expression of the genetic product.

Dysautonomia, Familial↗

Assessing function and pathology in familial dysautonomia: assessment of temperature perception, sweating and cutaneous innervation.

This study was performed to assess cutaneous nerve fibre loss in conjunction with temperature and sweating dysfunction in familial dysautonomia (FD). In ten FD patients, we determined warm and cold thresholds at the calf and shoulder, and sweating in response to acetylcholine iontophoresis over the calf and forearm. Punch skin biopsies from calf and back were immunostained and imaged to assess nerve fibre density and neuropeptide content. Mean temperature thresholds and baseline sweat rate were elevated in the patients, while total sweat volume and response time did not differ from controls. The average density of epidermal nerve fibres was greatly diminished in the calf and back. There was also severe nerve loss from the subepidermal neural plexus (SNP) and deep dermis. The few sweat glands present within the biopsies had had reduced innervation density. Substance P immunoreactive (-ir) and calcitonin gene related peptide-ir (CGRP-ir) were virtually absent, but vasoactive intestinal peptide-ir (VIP-ir) nerves were present in the SNP. Empty Schwann cell sheaths were observed. Temperature perception was more impaired than sweating. Epidermal nerve fibre density was found to be profoundly reduced in FD. Decreased SP and CGRP-ir nerves suggest that the FD gene mutation causes secondary neurotransmitter depletions. Empty Schwann cell sheaths and VIP-ir nerves suggest active denervation and regeneration.

Adolescent↗

Rescue of a human mRNA splicing defect by the plant cytokinin kinetin.

The defective splicing of pre-mRNA is a major cause of human disease. Exon skipping is a common result of splice mutations and has been reported in a wide variety of genetic disorders, yet the underlying mechanism is poorly understood. Often, such mutations are incompletely penetrant, and low levels of normal transcript and protein are maintained. Familial dysautonomia (FD) is caused by mutations in IKBKAP, and all cases described to date involve an intron 20 mutation that results in a unique pattern of tissue-specific exon skipping. Accurate splicing of the mutant IKBKAP allele is particularly inefficient in the nervous system. Here we show that treatment with the plant cytokinin kinetin alters splicing of IKBKAP. Kinetin significantly increases inclusion of exon 20 from the endogenous gene, as well as from an IKBKAP minigene. By contrast the drug does not enhance inclusion of alternatively spliced exon 31 in MYO5A. Benzyladenine, the most closely related cytokinin, showed a similar but less dramatic effect. Our findings reveal a remarkable impact on splicing fidelity by these small molecules, which therefore provide new tools for the dissection of mechanisms controlling tissue-specific pre-mRNA splicing. Further, kinetin should be explored as a treatment for increasing the level of normal IKAP in FD, and for other splicing disorders that may share a similar mechanism.

Adenine↗

Familial dysautonomia.

Familial dysautonomia (FD) is a neurodevelopmental genetic disorder within the larger classification of hereditary sensory and autonomic neuropathies, each caused by a different genetic error. The FD gene has been identified as IKBKAP. Mutations result in tissue-specific expression of mutant IkappaB kinase-associated protein (IKAP). The genetic error probably affects development, as well as maintenance, of neurons because there is neuropathological and clinical progression. Pathological alterations consist of decreased unmyelinated and small-fiber neurons. Clinical features reflect widespread involvement of sensory and autonomic neurons. Sensory loss includes impaired pain and temperature appreciation. Autonomic features include dysphagia, vomiting crises, blood pressure lability, and sudomotor dysfunction. Central dysfunction includes emotional lability and ataxia. With supportive treatment, prognosis has improved greatly. About 40% of patients are over age 20 years. The cause of death is usually pulmonary failure, unexplained sudden deaths, or renal failure. With the discovery of the genetic defect, definitive treatments are anticipated.

Autonomic Nervous System↗

Growth hormone treatment in children with familial dysautonomia.

OBJECTIVE: To assess experience with growth hormone (GH) therapy in patients with familial dysautonomia (FD). Study design Of 580 patients with FD registered at the Dysautonomia Center at New York University Medical Center, 13 patients (8 males, 5 females) aged 1.10 to 15.10 years received GH treatment. GH doses ranged from 0.2 to 0.3 mg/kg/wk; one patient received 0.14 mg/kg/wk. Information regarding auxologic data, skeletal age, pubertal status, and spinal deformity before and after GH therapy was obtained from center records and treating endocrinologists. Growth velocity was analyzed before and during GH treatment at 0 to 6 months, 6 to 12 months, 1 to 2 years, and >2 years. RESULTS: Before GH therapy, growth velocity was <5 cm/y in 10 patients and 5 to 6 cm/y in three patients. In the first six months of GH therapy, growth velocity exceeded pretreatment rates in all but one patient; 10 patients achieved an annualized growth rate >7 cm/y. Six of nine patients treated for more than one year grew >5 cm/y. Less than optimal treatment responses were attributed to poor compliance, intercurrent illness, scoliosis, or advanced puberty. CONCLUSION: The data demonstrate that GH treatment in patients with FD may increase growth velocity, at least in the short term. This experiential data supports a future prospective study.

Adolescent↗

Identification of the first non-Jewish mutation in familial Dysautonomia.

Familial Dysautonomia is an autosomal recessive disease with a remarkably high carrier frequency in the Ashkenazi Jewish population. It has recently been estimated that as many as 1 in 27 Ashkenazi Jews is a carrier of FD. The FD gene has been identified as IKBKAP, and two disease-causing mutations have been identified. The most common mutation, which is present on 99.5% of all FD chromosomes, is an intronic splice site mutation that results in tissue-specific skipping of exon 20. The second mutation, R696P, is a missense mutation that has been identified in 4 unrelated patients heterozygous for the major splice mutation. Interestingly, despite the fact that FD is a recessive disease, normal mRNA and protein are expressed in patient cells. To date, the diagnosis of FD has been limited to individuals of Ashkenazi Jewish descent and identification of the gene has led to widespread diagnostic and carrier testing in this population. In this report, we describe the first non-Jewish IKBKAP mutation, a proline to leucine missense mutation in exon 26, P914L. This mutation is of particular significance because it was identified in a patient who lacks one of the cardinal diagnostic criteria for the disease-pure Ashkenazi Jewish ancestry. In light of this fact, the diagnostic criteria for FD must be expanded. Furthermore, in order to ensure carrier identification in all ethnicities, this mutation must now be considered when screening for FD.

Child, Preschool↗

Tissue-specific reduction in splicing efficiency of IKBKAP due to the major mutation associated with familial dysautonomia.

We recently identified a mutation in the I-kappa B kinase associated protein (IKBKAP) gene as the major cause of familial dysautonomia (FD), a recessive sensory and autonomic neuropathy. This alteration, located at base pair 6 of the intron 20 donor splice site, is present on >99.5% of FD chromosomes and results in tissue-specific skipping of exon 20. A second FD mutation, a missense change in exon 19 (R696P), was seen in only four patients heterozygous for the major mutation. Here, we have further characterized the consequences of the major mutation by examining the ratio of wild-type to mutant (WT:MU) IKBKAP transcript in EBV-transformed lymphoblast lines, primary fibroblasts, freshly collected blood samples, and postmortem tissues from patients with FD. We consistently found that WT IKBKAP transcripts were present, albeit to varying extents, in all cell lines, blood, and postmortem FD tissues. Further, a corresponding decrease in the level of WT protein is seen in FD cell lines and tissues. The WT:MU ratio in cultured lymphoblasts varied with growth phase but not with serum concentration or inclusion of antibiotics. Using both densitometry and real-time quantitative polymerase chain reaction, we found that relative WT:MU IKBKAP RNA levels were highest in cultured patient lymphoblasts and lowest in postmortem central and peripheral nervous tissues. These observations suggest that the relative inefficiency of WT IKBKAP mRNA production from the mutant alleles in the nervous system underlies the selective degeneration of sensory and autonomic neurons in FD.Therefore, exploration of methods to increase the WT:MU IKBKAP transcript ratio in the nervous system offers a promising approach for developing an effective therapy for patients with FD.

Alternative Splicing↗

Hereditary dysautonomias: current knowledge and collaborations for the future.

The hereditary dysautonomias (H-Dys) are a large group of disorders that affect the autonomic nervous system. Research in the field of H-Dys is very challenging, because the disorders involve interdisciplinary, integrative, and "mind-body" connections. Recently, medical scientists, NIH/NINDS representatives, and several patient support groups gathered for the first time in order to discuss recent findings and future directions in the H-Dys field. The H-Dys workshop was instrumental in promoting interactions between basic science and clinical investigators. It also allowed attendees to have an opportunity to meet each other, understand the similarities between the various forms of dysautonomia, and experience the unique perspective offered by patients and their families. Future advances in H-Dys research will depend on a novel multi-system approach by investigators from different medical disciplines, and it is hoped that towards a common goal, novel "bench-to-bedside" therapeutics will be developed to improve the lives of, or even cure, patients suffering from dysautonomic syndromes.

Animals↗