1001 Intravenous Ferric Carboxymaltose For Restless Legs Syndrome In Children And Adolescents

Introduction

Substantial scientific evidence implicates brain iron deficiency in the pathophysiology of restless legs syndrome (RLS). Current clinical guidelines recommend oral and intravenous iron (IV) in the treatment of both adult and pediatric RLS but studies using ferric carboxymaltose (FCM) are lacking in children and adolescents.

Methods

Retrospective case series of children and adolescents with RLS treated with IV FCM who had serum ferritin levels <50 μg/L. Patients were offered a single dose of IV FCM, 15 mg/kg if weighting <50 kg or 750 mg if weighting >50 kg. Iron profile, serum ferritin, and severity assessment by the International Restless Legs Study Group severity scale (IRLS) were collected pre- and post-infusion. Clinical Global Impression Scale (CGI) was used instead of the IRLS for children. Phosphorus level and adverse effects were assessed post-infusion in all patients. Age and sex-matched children with RLS treated with oral iron supplementation (mean dosage 1.5±0.62 mg/kg/day) were included as a comparison group.

Results

Twenty-eight subjects (15 females, mean age 11.5 years, SD 4.23) and 24 controls were included. Baseline ferritin levels were not significantly different from those of controls but increased significantly from 13.9±7.02 to 112.9±12.00 μg/L after 8 weeks from infusion (p<0.000001), when they were also significantly higher than control values (34.2±21.64 μg/mL, p<0.000001). Transferrin saturation increased from 22.8±9.77% to 31.7±6.81% (p<0.0001), total iron binding capacity decreased from 366.7±51.32 to 302.0±37.83 μg/dL (p<0.0000035). RLS was reported to be resolved or improved in all children treated with IV iron (vs. 62.5% of controls) while none of them reported no change (vs. 37.5% of controls; Chi-square test 9.84, p<0.002). IRLS Score decreased in adolescents from 30.7±22.68 to 3.2±4.21 (p<0.000008) while CGI-I was “very much improved” in six children and “much improved” in four. Side effects were reported in 17.8% of patients treated IV and 20.8% controls (Chi-square 0.0169, p=0.897). FCM side effects included lightheadedness and gastrointestinal discomfort. Post IV phosphorus levels were normal in all participants.

Conclusion

This open-label, observational and retrospective study indicates that FCM IV infusion is an effective treatment for pediatric RLS with higher efficacy than oral iron supplementation.

Support

 

Cerebral hemiatrophy with superficial siderosis and PLEDs due to a germ cell tumor of the basal ganglia

The diagnosis of basal ganglia germ cell tumors may be delayed due to slow progression and minimal early changes on magnetic resonance imaging (MRI). The cystic nature of some tumors may lead to non-diagnostic biopsies. We describe the clinical, imaging, laboratory, and postmortem findings of a basal ganglia germ cell tumor in a 19-year-old man. Clues to an early antemortem diagnosis based on MRI findings and determination of tumor markers are discussed. An early diagnosis and accurate characterization of basal ganglia germ cell tumors is essential for optimal therapy. The presence of cerebral hemiatrophy and hemorrhagic or cystic components is suggestive. Measurement of serum and cerebrospinal fluid markers such as human chorionic gonadotropin may suggest the diagnosis.

Progressive infantile axonal polyneuropathy

Polyneuropathies are relatively uncommon in early infancy and the majority of affected children are found to have hypomyelinating neuropathies. Axonal sensorimotor neuropathies have been described in childhood but the majority of affected children present at or after 6 months of age, have nonprogressive courses, and achieve the ability to walk, albeit late. Here we present three infants with infantile progressive axonal polyneuropathy from two families with nonconsanguineous parents. Each child presented shortly after the neonatal period and with rapid progression to quadriplegia. Involvement of the lower cranial nerves, phrenic nerves, or both was present in each child. Electrophysiology was diagnostic in each child. While the diagnosis of spinal muscular atrophy was considered in each case, clinical presentation, biopsies, and genetic testing were inconsistent with this diagnosis. Recognition of this early form of progressive axonal neuropathy is important as respiratory compromise occurred early and the condition showed familial inheritance in two of our patients.

Autonomic cardiovascular control in children with obstructive sleep apnea

Autonomic cardiorespiratory control changes with sleep-wake states and is influenced by sleep-related breathing disorders. Power spectrum (PS) analysis of instantaneous fluctuations in heart rate (HR) is used to investigate the role of the autonomic nervous system (ANS) in cardiorespiratory control. The two spectral regions of interest are the low frequency component (LF) and high frequency component (HF). The aim of the present study was to investigate the autonomic cardiorespiratory control in children with obstructive sleep apnea (OSA) syndrome. We studied 10 children with OSA versus 10 normal children. All subjects underwent whole night polysomnography. Spectral analysis of the HR and breathing signals was performed for 256 second long, artifact-free epochs in each sleep-wake state. The LF power was higher in the OSA group compared with control subjects for all states, reflecting enhanced sympathetic activity in OSA subjects. The results indicated sympathetic predominance during REM sleep in all subjects and parasympathetic predominance in slow wave sleep only in controls. The autonomic balance (LF/HF) was significantly higher in OSA patients than in control subjects, at all stages during night sleep, and while awake before sleep onset. An index of overall autonomic balance (ABI) was computed for each subject and correlated well with the measured respiratory disturbance index (RDI).

A child with reading impairment and a family history of adrenoleukodystrophy

The clinical course of a 6-year-old boy with adrenoleukodystrophy (ALD) who underwent allogeneic stem-cell transplantation during an early clinical stage is described. Twenty-three months after transplant, he remains neurologically stable, but with moderate neurological sequelae; the serum very long chain fatty acid profile has improved, but not normalized. The indications, mechanism of action, and complications of bone marrow transplantation in ALD are discussed briefly, along with other potential therapies.

Bone marrow transplantation for the treatment of alpha-mannosidosis

We report successful bone marrow transplantation in a child with a severe form of alpha-mannosidosis, type I. There was complete resolution of the recurrent sinopulmonary disease and organomegaly, improvement in the bony disease, and stabilization of neurocognitive function.

Sleep disorders in school-age children

This article on school age children reviews relevant issues in sleep physiology, the classification of sleep disorders, their clinical and laboratory assessment, some common sleep disorders, the sleep-epilepsy relationship, as well as the impact of daytime sleepiness on higher cortical functions.

Sleep apnea in patients receiving growth hormone

Among 145 patients treated with recombinant human growth hormone (GH), four developed sleep apnea (two obstructive, two mixed) associated with tonsillar and adenoidal hypertrophy in three. These four patients had no local risk factors predisposing to upper airway obstruction (i.e., frequent pharyngitis or sinusitis). Clinical and/or polysomnographic features of sleep apnea improved following cessation of GH therapy in one patient, and following tonsillectomy and adenoidectomy in all patients. The present observations indicate that, albeit rarely, obstructive and/or central sleep apnea may occur in children treated with GH. Polysomnography should be considered if symptoms of snoring, interrupted sleep, daytime somnolence-particularly if associated with tonsillar hypertrophy-appear in children during GH therapy.

Excessive daytime sleepiness in a 13-year-old

Included in the large group of children referred for attention deficit evaluations, several less common entities can be found. Careful history will enable the identification of these atypical cases of attention deficit and allow more precise diagnosis and treatment.

Myeloradicular features as the initial presentation of sarcomas of childhood

Sarcomas (chondrosarcoma, Ewing sarcoma, rhabdomyosarcoma, and undifferentiated sarcoma) generally present with nonneurologic symptoms at the onset. Five children with sarcomas who presented with spinal cord compression or radiculopathy as their initial problems are described. These patients appear to be older than those with the more commonly encountered neuroblastoma-related spinal cord compression. Our patients had a favorable neurologic recovery initially, but ultimately succumbed to systemic complications from spread of the sarcoma.

The laboratory assessment of daytime sleepiness in childhood

Excessive daytime sleepiness is a disabling symptom of diverse etiologies. This article reviews the various, currently available diagnostic techniques that can be applied in the evaluation of childhood hypersomnolence, along with their merits and limitations. Normal polysomnographic data of children differ from those of adults. Serial studies may be required in evolving childhood narcolepsy for establishing a definitive diagnosis.

Narcolepsy in children

Childhood narcolepsy is frequently under-diagnosed. Hypersomnolence may not always be accompanied by cataplexy, sleep paralysis, or hypnagogic hallucinations in the early stages. Pathophysiologic considerations revolve around an altered central nervous system catecholamine-acetylcholine balance. Both idiopathic and symptomatic forms have been described. Serial polysomnography and multiple sleep latency tests may be required to establish a definitive diagnosis. The long-term management requires the provision of both pharmacological and non-pharmacological forms of therapy.

Fluctuations in autonomic nervous activity during sleep displayed by power spectrum analysis of heart rate variability

OBJECTIVE

The use of an efficient noninvasive method to investigate the autonomic nervous system and cardiovascular control during sleep.

BACKGROUND

Beat-to-beat heart rate variability displays two main components: a low-frequency (LF) one representing sympathetic and parasympathetic influence and a high-frequency (HF) component of parasympathetic origin. Sympathovagal balance can be defined as LF/HF ratio.

METHODS/DESIGN

We reviewed normal, standardly staged all-night polysomnograms from 10 healthy children aged 6 to 17 years. Recorded 256-second traces of heart rate and respiration were sampled. Power spectra of instantaneous heart rate and respiration were computed using a fast Fourier transform method.

RESULTS

The study revealed a decrease in LF during sleep, with minimal values during non-REM slow-wave sleep and elevated levels similar to those of wakefulness during REM. HF increased with sleep onset, reaching maximal values during slow-wave sleep, and behaved as a mirror image of LF. LF/HF ratio displayed changes similar to those in LF.

CONCLUSION

The sympathetic predominance that characterizes wakefulness decreases during non-REM sleep, is minimal in slow-wave sleep, and surges toward mean awake levels during REM sleep. The autonomic balance is shifted toward parasympathetic predominance during slow-wave sleep. This noninvasive method used to outline autonomic activity achieves results that are in complete agreement with those obtained with direct invasive tools.

Sleep abnormalities in patients with severe cerebral palsy

The all-night polysomnographic findings of nine patients with spastic quadriparesis (mean age 36.7 months) were analysed retrospectively and compared with those of nine age-matched controls (mean age 37.4 months). The cerebral palsy group had significantly more respiratory disturbances per hour of sleep, with five of nine being diagnosed as having obstructive sleep apnea. They also had fewer changes in body position during the night. Interictal epileptiform discharges averaged 23.3 per cent of the total arousals in the cerebral palsy group. Obstructive apnea, decreased ability to change body position, and interictal epileptiform discharges are prevalent in the sleep of patients with severe cerebral palsy, and contribute towards its disruption.

Ependymal abnormalities in lissencephaly/pachygyria

The ependyma was examined in eight children with neuroblast migratory disorders of diverse origin: three cases of lissencephaly type 1 with severe to mild degrees of agyria/pachygyria, four cases of lissencephaly type 2 in Fukuyama muscular dystrophy and the Walker-Warburg syndrome, and one case of hemimegalencephalic pachygyria. Morphological and immunohistochemical abnormalities of the ependyma were strikingly similar in all. Discontinuities were disproportionate to the degree of ventriculomegaly. In some regions, the ependyma remained a pseudostratified columnar epithelium, though basal processes were absent. The poles of the horns of the lateral ventricles were replaced by extensive heterotopic ependymal rosettes. Rosettes and rows of ependyma also were in other subventricular sites. Subependymal nodules of large astrocytes and their processes bulged into the ventricular lumen after infancy. Ependymal cells did not express glial fibrillary acidic protein, but showed persistent expression of S-100 protein, cytokeratin CK-904 and sometimes vimentin long after these proteins normally disappear. An abnormal ependyma in lissencephaly/pachygyria may contribute to disturbances in neuronogenesis, guidance of axonal projections and neuroblast migrations; it may be a primary factor in pathogenesis.

Syringomyelia presenting as cricopharyngeal pseudostricture

A 14-year-old boy was referred for evaluation of a cervical esophageal "stricture" diagnosed by upper gastrointestinal radiograph, which had been performed for evaluation of dysphagia and dysphonia of several months' duration. Neurological examination revealed several cranial nerve abnormalities and hyperreflexia, raising the suspicion of a cervicomedullary junction lesion. However, computed tomography of the head, neck, and spine was completely normal. Findings on the swallowing videofluoroscopy were interpreted as consistent with a stricture (a "tight constriction distal to the pyriform sinus"). However, no evidence for this was found by either esophagoscopy or esophageal manometry, which revealed a low-pressure cervical esophageal sphincter. Neurologic evaluation was pursued with magnetic resonance imaging, which revealed a large syrinx extending from C2 to T2 segments. We report this case to point out the importance of considering neurologic disease in the differential diagnosis of "stricture" of the cervical esophagus.

Characteristics of narcolepsy in preteenaged children

Narcolepsy is rarely diagnosed in preteenaged children. Its clinical and polysomnographic manifestations, some of which are unusual, are described in four children who were observed prospectively. The mean age at onset of hypersomnia was 10.2 years (range 8.4 to 11.2 years). Daytime naps among these children were lengthy, ranging from 20 to 120 minutes, and generally were considered unrefreshing. Cataplexy was present at the onset in all four children. Three of the four children were obese, with the concurrent nocturnal snoring prompting a misleading concern about obstructive sleep apnea syndrome in two children. The histocompatibility DR2 antigen was present in all four children. Significant behavioral manifestations appeared in all of them. The response to stimulant medications was, at best, modest. Narcolepsy may be difficult to diagnose in this age group. However, a careful history eliciting sleep/wake dysfunction (including cataplexy), leukocyte assays for the histocompatibility DR2 antigen, and serial polysomnographic studies may enable early recognition and treatment of this disease.

Impaired NADH-CoQ reductase activity in a child with moyamoya syndrome

A 33-month-old boy with recurrent stroke-like episodes had angiographic features characteristic of moyamoya syndrome. Mitochondrial encephalomyopathy was suspected because of lactic acidosis and ptosis. Studies of oxidative metabolism on isolated skeletal muscle mitochondria revealed impairment of NADH-coenzyme Q reductase activity. Mitochondrial metabolic disorders may cause moyamoya syndrome when other known associated factors are absent.

Conservative management of spinal epidural hematoma in hemophilia

Two patients with hemophilia and spinal epidural hematoma, who were treated successfully with serial Factor VIII infusions, are reported. This form of conservative therapy may circumvent the need for decompressive laminectomy and its attendant complications in instances in which the neurologic deficit is mild or stable. Somatosensory evoked potential studies were useful in documenting spinal cord dysfunction in 1 of the 2 patients.

Neonatal diaphragmatic hernia. An improving outlook with extracorporeal membrane oxygenation

In a 15-year period, 89 newborns were treated for congenital diaphragmatic hernia. The patients were divided into three groups, depending on postoperative therapeutic support available: group 1, ventilator therapy only; group 2, ventilator therapy plus pulmonary vasodilators (tolazoline hydrochloride); and group 3, ventilators, tolazoline, and/or extracorporeal membrane oxygenation (ECMO). The three groups were identical for presenting symptoms, signs, and preoperative blood gas determinations. The survival for each group was as follows: group 1, 17 (40%) of 42; group 2, 14 (45%) of 31; and group 3, 12 (75%) of 16. Complications requiring further operations were identical. All survivors in groups 1 and 2 are normal developmentally, while one of five group 3 ECMO survivors has developmental delay and another has long-term ventilator dependence. These data suggest that ECMO, an invasive technique for newborn respiratory failure, improves survival in congenital diaphragmatic hernia.

Extracorporeal membrane oxygenation for newborn respiratory failure

Jugular vein-carotid artery extracorporeal membrane oxygenation (ECMO) was utilized in 22 newborns (16 male and 6 female) 1 to 12 days old with respiratory failure due to meconium aspiration (12 patients), diaphragmatic hernia (4), persistent fetal circulation (3), hyaline membrane disease (2), and Rh incompatibility (1). Prior to ECMO, all patients had alveolar-arterial O2 pressure gradients greater than 580 mm Hg (predicted mortality greater than 90%), weighed more than 1,800 gm, had a gestation period of longer than 35 weeks, and had no cerebral hemorrhage. The duration of ECMO was 41 to 310 hours (mean, 134.5 hours). Nineteen (86%) of the 22 patients survived ECMO. Death was caused by lung disease (2) and cerebral hemorrhage (1). Four other patients died 6 to 40 days after ECMO of pulmonary hypoplasia (1), pneumonia (1), cerebral edema (1), and hepatorenal failure (1). Complications during ECMO were few and easily managed. Fifteen infants (68%) are alive 1 to 18 months after ECMO. Three have neurological deficit (2 severe, 1 mild). Bayley Developmental Examinations in 4 survivors now more than 12 months old are normal. Extracorporeal membrane oxygenation is an aggressive but effective technique of life support in newborns refractory to conventional respiratory management. Potential complications of ECMO mandate strict aseptic technique, constant monitoring, and multidisciplinary patient management.

AB variant GM2 gangliosidosis: cerebrospinal fluid and neuropathologic characteristics

A child with AB variant GM2 gangliosidosis who had progressive intellectual deterioration and seizures commencing at the age of 12 months is described. Neuronal loss, and neuronal and astrocytic inclusions characteristic of the gangliosidoses, were seen on cortical biopsy. GM2 ganglioside was detected in the CSF. As CNS ganglioside accumulation in this condition occurs in the presence of normal leukocyte hexosaminidase A and B levels, spinal fluid assay for GM2 ganglioside may serve as a valuable aid in diagnosis.

Hypersomnia, bithalamic lesions, and altered sleep architecture in Kearns-Sayre syndrome

An 11-year-old boy with Kearns-Sayre syndrome developed hypersomnia associated with bithalamic lesions and had complete absence of sleep spindles on a nocturnal polysomnogram.

"Locked-in" state following Reye's syndrome

A 12-year-old boy with Reye's syndrome had an initial course complicated by increased intracranial pressure and systemic hypotension. He subsequently developed brainstem damage producing permanent apnea and a "locked-in" state. Nevertheless, the normal architecture of sleep was retained, as was a high degree of intelligence.

Symmetric bithalamic and striatal hemorrhage following perinatal hypoxia in a term infant

A full-term infant who demonstrated a prolonged period of obtundation following asphyxia at birth was found on cranial computed tomography (CT) to have hemorrhage limited exclusively to symmetric bithalamic and striatal areas. This pattern of discrete, symmetric nuclear hemorrhage has not so far been reported as a complication of birth asphyxia. It differs from the germinal matrix hemorrhage on one hand in having a later time of onset (between the 4th and 10th day of life). It is also distinct from the more common supratentorial parenchymal hemorrhages in full-term infants owing to its topography, consequent interruption of the thalamocortical arousal mechanisms, and prolonged period of obtundation.

Neurologic, psychiatric, and cardiovascular complications in children struck by lightning

The neurologic changes following lightning injury include coma with cerebral edema, inappropriate secretion of antidiuretic hormone (ADH), seizures, cerebellar ataxia, and painful sensory disturbances. Deteriorating neurologic status may warrant the use of intracranial pressure monitoring devices. Myocardial injury and transient hypertension are generally evident at the onset. Monitoring of the cardiac rhythm may be needed for as long as a week for late onset arrythmia. Abnormalities of memory, mood, and affect noted on recovery of consciousness may persist for months, necessitating close psychiatric and neurlologic follow-up.

Auditory evoked potentials in bacterial meningitis

Auditory evoked potentials obtained on infants and children recovering from bacterial meningitis are effective in early and reliable detection of sensorineural deafness, particularly in those who demonstrate absence of wave I.

Chorea as a manifestation of bilateral subdural hematoma in an elderly man

As in a previously described child with unilateral subdural hematoma, bilateral subdural hematoma in the adult can also be associated with reversible chorea.

Congenital cervical spinal atrophy

Three children presented at birth with axial hypotonia and symmetrical flaccid paresis limited to the upper extremities, and involving proximal and distal muscle groups. At birth, palmar flexion creases were poorly developed, and the hand muscles were atrophic. These clinical features, the muscle biopsy findings, and the nonprogressive course, suggest a vascular insult to the cervical spinal cord during gestation. The term, congenital cervical spinal atrophy seems most descriptive of these features.

Cerebral embryopathy in late first trimester: possible association with swine influenza vaccine

An infant girl was born with cerebral malformations characterized by developmental arrest late in the first trimester of gestation. These features included persistent pontine flexure, cerebellum developed only around the rhombic lip, failure of migration of inferior olive, absence of basis pontis and of corticospinal and corticopontine tracts, and agenesis of olfactory bulbs. The cerebral cortex was thin and poorly laminated, and primary and secondary sulci had failed to form. The choroid plexus contained vascular malformations, hemorrhages, and infarcts. The leptomeninges contained foci of primitive mesenchyme. The mother had received an inoculation of swine influenza vaccine six weeks after conception, followed by a 2-week illness. The temporal relation to the timing of the cerebral malformation suggests a teratogenic effect of the vaccine, but may have been coincidental.