Biomedical subjects

Nathan Watemberg

Publications and source records attributed to Nathan Watemberg.

At least 19 recordsLinked to original sources

PubMed2007

Hypomyelinating leukoencephalopathy with paroxysmal tonic upgaze and absence of psychomotor development.

Hypomyelinating leukoencephalopathies are characterized by a substantial and permanent deficit in myelin deposition in the brain. Although our knowledge and understanding of the etiology of white matter diseases has progressively increased, many cases with this disorder remain undiagnosed, despite extensive evaluations. Recently, new disease entities have been defined by combining magnetic resonance imaging pattern recognition and clinical features. We describe a 1-year-old Ashkenazi Jewish girl with a hypomyelinating leukoencephalopathy, who presented in the neonatal period with episodes of sustained paroxysmal tonic upward gaze, roving eye movements, pendular nystagmus, and severe hypotonia, with the later appearance of pyramidal and extrapyramidal signs and no development. In addition, she has dysmorphic signs. This clinical picture is not consistent with any of the previously described hypomyelinating leukoencephalopathies and may represent a new entity.

Basal Ganglia Diseases↗

PubMed2006

A benign congenital myopathy in an inbred Samaritan family.

We describe a novel form of myopathy in a mother and her two daughters from an inbred Samaritan family. The patients displayed severe neonatal hypotonia, lethargy and dysmorphic features. Motor milestones were delayed; however, the hypotonia and muscle weakness gradually improved during the first 2 years of life and independent walking was achieved by 18 months. The mother at the age of 23 years shows myopathic facies and minimal proximal weakness. Her intelligence is normal. Her muscle biopsy revealed central nuclei and disruption of the intermyofibrillary network with moth eaten and spiral fibers. Mutations in SMN, MTM1 and the myotonic dystrophy genes were excluded. We suggest this is a new benign form of congenital myopathy. Inheritance is probably autosomal recessive.

Abnormalities, Multiple↗

PubMed2006

Acute steroid responsive small-fiber sensory neuropathy: a new entity?

Small-fiber neuropathy is often idiopathic and commonly follows a chronic course. Treatment is often effective in treating the core symptom of pain, but it has no effect on the pathologic process. We describe four patients with acute small-fiber neuropathy who responded dramatically to steroid therapy. All patients had acute onset neuropathic pain, normal nerve conduction studies, and evidence of small-fiber dysfunction in quantitative sensory testing and skin biopsy. Symptoms were distal and symmetrical in three patients and generalized in one patient. In two cases, the neuropathy presented as an erythromelalgia-like syndrome. Marked clinical improvement occurred 1-2 weeks after oral prednisone therapy was initiated. Three patients remained symptom free, and one patient experienced recurrence of neuropathy after prednisone was tapered.

Adolescent↗

PubMed2006

Acute heroin-related neuropathy.

Heroin-related peripheral nervous injury has scarcely been reported, mostly as compressive neuropathy. Rarely, other types of peripheral nervous system (PNS) injury have been recognized, such as plexopathy, polyradiculopathy, mononeuropathy, and rhabdomyolysis. These complications are usually not related to local trauma, but the nature of nerve injury remains unknown. Immunologic mechanisms have been proposed, although generally there is no laboratory evidence of inflammation and usually there is no improvement following steroid therapy. We describe six patients who developed acute PNS injury following intravenous or intranasal heroin self-administration with no evidence of compression injury or inflammation. Four patients had plexopathy (two lumbosacral and two brachial), and two had symmetric distal axonal sensorimotor neuropathy affecting the lower extremities. Of the six patients, five had concomitant rhabdomyolysis (creatine kinase, CK: 5,000-100,000 U/l) and one patient with brachial plexopathy had normal CK levels. The neurological deficit was noticed 3-36 h after heroin administration. Electromyography in five patients was consistent with sensorimotor axonal loss either confined to the affected plexus or with a diffuse distribution in the legs in the two patients with neuropathy. We propose that a toxic mechanism may be responsible for non-compression cases of acute neuropathy following heroin abuse.

Adult↗

PubMed2006

Encephalopathy associated with Hashimoto thyroiditis: pediatric perspective.

In recent years, neuropsychiatric symptoms associated with Hashimoto thyroiditis have been increasingly recognized in both adult and pediatric patients. This neurologic complication has been termed "Hashimoto encephalopathy," and it can begin abruptly, in the form of seizures or agitation, with or without other neurologic complaints, or it can develop gradually, in a relapsing-remiting manner, including, among others, cognitive deterioration and psychiatric illness. The occurrence of Hashimoto encephalopathy is unrelated to the patient's thyroid function status. Although the pathogenesis of this encephalopathy is not fully understood, evidence for both autoimmune and vasculitic mechanisms exists. Owing to a low index of suspicion, this encephalopathy is very likely underdiagnosed in children. The diagnosis of Hashimoto encephalopathy is based on detecting antithyroid antibodies in these patients, although there is no correlation between antibody levels and the severity of the illness. Cerebrospinal fluid analysis, electroencephalography, and neuroimaging studies do not show consistent findings to support the diagnosis. Physicians' awareness of this complication is of great importance because most patients respond dramatically to corticosteroid therapy. Moreover, early recognition might also avoid an expensive diagnostic work-up in patients with unexplained encephalopathy (J Child Neurol 2006;21:1-5).

Acute Disease↗

PubMed2006

Fat intolerance in developmentally impaired children with severe feeding intolerance.

Children with a variety of genetic, metabolic, and neurologic disorders can suffer from severe feeding intolerance that is unresponsive to medical, surgical, and nutritional therapy. Developmentally disabled tube-fed children with severe upper gastrointestinal symptoms that persisted after fundoplication who were unresponsive to all medical, surgical, and nutritional interventions underwent a thorough gastrointestinal evaluation, including gastroscopy, pH-metry, upper gastrointestinal barium series, and gastric emptying studies. They were placed on a low-fat diet, and the symptoms before and after the diet were compared. The patients were then rechallenged with incremental increases in fat until the symptoms recurred or the patients reached their former fat concentration. Six children meeting the study criteria were evaluated. Four of these patients had a significant improvement in symptoms, oral intake and feeding tolerance with a decrease in fat intake, and relapse of symptoms when fat calories were increased. Improvement occurred in children who had been intolerant to duodenal feeding. We were subsequently able to wean two children from tube feeding. Dietary fat can provoke upper gastrointestinal symptoms in children with gastric and intestinal dysmotility. Short-term manipulation of dietary fat intake can improve tolerance to feeding.

Child, Preschool↗

PubMed2006

Nonprogressive familial leukoencephalopathy with porencephalic cyst and focal seizures.

Two siblings with a similar white-matter disease but different clinical symptoms are described. The first sibling suffers from nonprogressive spastic hemiparesis secondary to a congenital periventricular porencephalic cyst. Her brother has focal epilepsy. On magnetic resonance imaging, both patients show diffuse white-matter involvement predominantly of the posterior periventricular area. We suggest that this is a familial white-matter disorder with minimal symptoms and no progression in early childhood.

Brain↗

PubMed2006

Ketamine increases opening cerebrospinal pressure in children undergoing lumbar puncture.

Intravenous ketamine, often administered concomitantly with midazolam, is one of the most commonly used drugs for procedural sedation in children. Although it is considered safe for use in children, ketamine can increase intracranial pressure. Hence, this study was carried out to determine whether adding ketamine to midazolam prior to performing lumbar puncture would be associated with a higher cerebrospinal fluid opening pressure in children with suspected aseptic meningitis. Thirty-nine children aged 6 months to 14 years were included: 26 in group A (intravenous midazolam plus ketamine) and 13 in group B (intravenous midazolam only). Mean cerebrospinal fluid opening pressure in group A was 24.4 cm H2O (median 23 cm H2O) compared with 20 cm H2O (median 19.8 cm H2O) in group B (P = .011). Intravenous ketamine prior to performing lumbar puncture is associated with a significantly higher lumbar cerebrospinal fluid opening pressure in children with aseptic meningitis. However, no outcome differences have been found between the two groups.

Adolescent↗

PubMed2006

Recurrent absence status epilepticus (spike-and-wave stupor) associated with lamotrigine therapy.

We report on the aggravation of absence seizures by lamotrigine leading to absence status epilepticus in a child. The patient is a 10-year-old girl with a history of absence seizures, learning disabilities, and hereditary neuropathy with liability to pressure palsies. Lamotrigine (up to 12 mg/kg/day) was prescribed after a brief course of valproate was associated with restlessness. Long-acting methylphenidate was also administered. The initial response to lamotrigine appeared to be excellent. The first episode of absence status epilepticus occurred during a febrile illness while lamotrigine was being gradually discontinued. Following this event, lamotrigine dose was increased to 10 mg/kg/day and methylphenidate was continued. Six weeks later, a second absence status epilepticus episode ensued without fever. Sulthiame and clonazepam were substituted for lamotrigine, whereas methylphenidate therapy was continued. A psychiatrist prescribed risperidone 1 month later owing to obsessive-compulsive behavior. Nine months later, she remained free of absence seizures. Whereas the first absence status epilepticus event could have been triggered by fever, the second episode occurred while the daily lamotrigine dose was being increased. Moreover, the patient is seizure free following lamotrigine discontinuation. Hence, it is quite possible that lamotrigine caused seizure aggravation and absence status epilepticus in this child.

Anticonvulsants↗

PubMed2006

Asymptomatic or minimally symptomatic hyperCKemia: histopathologic correlates.

BACKGROUND: Persistent creatine kinase elevation is occasionally encountered in subjects without any clinical manifestation of a neuromuscular disorder or any condition known to be associated with increased serum CK levels. It is still unresolved whether extensive investigations and specifically a muscle biopsy should be performed in clinically normal individuals with elevated CK levels. OBJECTIVE: To study the muscle pathology of patients with asymptomatic or minimally symptomatic hyperCKemia. METHODS: The clinical and laboratory data of patients with persistent hyperCKemia and normal neurologic examination were reviewed and their muscle biopsies evaluated. RESULTS: The study group included 40 patients aged 7-67 years; the male to female ratio was 3:1. Nineteen patients were completely asymptomatic, 20 had mild non-specific myalgia, and 1 had muscle cramps. Electromyography was performed in 27 patients and showed myopathic changes in 7 (26%). Abnormal muscle biopsy findings (e.g., increased variation in fiber size, increased number of central nuclei, and occasional degenerating fibers) were detected in 22 of the 40 patients (55%). No fat or glycogen accumulation was detected. Immunohistochemistry demonstrated abnormal dystrophin staining in 3 patients (8%), resembling the pathologic changes of Becker muscular dystrophy. No abnormal findings were detected on immunohistochemical staining for merosin, dysferlin, caveolin 3, or alpha and gamma sarcoglycans. The EMG findings did not correlate with the pathologic findings. CONCLUSIONS: Abnormal muscle biopsies were found in 55% of patients with asymptomatic or minimally symptomatic hyperCKemia. Specific diagnosis of muscular dystrophy, however, was possible in only 8% of the patients.

Adolescent↗

PubMed2005

Adding video recording increases the diagnostic yield of routine electroencephalograms in children with frequent paroxysmal events.

PURPOSE: To report on the usefulness of adding video recording to routine EEG studies of infants and children with frequent paroxysmal events. METHODS: We analyzed the efficacy of this diagnostic means during a 4-year period. The decision whether to add video recording was made by the pediatric EEG interpreter at the time of the study. Studies were planned to last between 20 and 30 min, and, if needed, were extended by the EEG interpreter. For most studies, video recording was added from the beginning of EEG recording. In a minority of cases, the addition of video was implemented during the first part of the EEG test, as clinical events became obvious. In these cases, a new study (file) was begun. The success rate was analyzed according to the indications for the EEG study: paroxysmal eye movements, tremor, suspected seizures, myoclonus, staring episodes, suspected stereotypias and tics, absence epilepsy follow-up, cyanotic episodes, and suspected psychogenic nonepileptic events. RESULTS: Video recording was added to 137 of 666 routine studies. Mean patient age was 4.8 years. The nature of the event was determined in 61 (45%) of the EEG studies. Twenty-eight percent were hospitalized patients. The average study duration was 26 min. This diagnostic means was particularly useful for paroxysmal eye movements, staring spells, myoclonic jerks, stereotypias, and psychogenic nonepileptic events. About 46% of 116 patients for whom cognitive data were available were mentally retarded. EEG with added video recording was successfully performed in all 116 cases and provided useful information in 29 (55%) of these 53 patients. CONCLUSIONS: Adding video recording to routine EEG was helpful in 45% of cases referred for frequent paroxysmal events. This technique proved useful for hospitalized children as well as for outpatients. Moreover, it was successfully applied in cognitively impaired patients. Infants and children with paroxysmal eye movements, staring spells, myoclonic jerks, stereotypias, and pseudoseizures especially benefited from this diagnostic means. Because of its low cost and the little discomfort imposed on the patient and his or her family, this technique should be considered as a first diagnostic step in children with frequent paroxysmal events.

Age Factors↗

PubMed2005

Pediatric refractory partial status epilepticus responsive to topiramate.

Topiramate was safely administered to two young children with refractory partial status epilepticus via nasogastric tube in rapid titration up to a very high total daily dose. An excellent clinical response occurred in both cases. Reaching high daily doses of topiramate within days allowed for safe discontinuation of other antiepileptic drugs in both patients. Given the high efficacy of rapidly titrated topiramate in our patients, this medication may be useful in some cases of pediatric refractory partial status epilepticus. However, more clinical studies on this therapeutic approach are needed to establish the precise role of topiramate in status epilepticus in children.

Anticonvulsants↗

PubMed2004

White matter involvement in mitochondrial diseases.

White matter involvement is recently being realized as a common finding in mitochondrial disorders. It is considered an inherent part of the classical mitochondrial syndromes which are usually associated with alterations in the mitochondrial DNA such as: Leigh disease, Kearns-Sayre syndrome, mitochondrial encephalomyopathy lactic acidosis, and stroke like episodes, mitochondrial neuro-gastro-intestinal encephalomyopathy and Leber's hereditary optic neuropathy. White matter involvement is also described in mitochondrial disorders due to mutations in the nuclear DNA which are transmitted in an autosomal pattern. MRI findings suggestive of a mitochondrial disease are: small cyst-like lesions in abnormal white matter, involvement of both cerebral and cerebellar white matter, and a combination of a leukoencephalopathy with bilateral basal ganglia lesions. The clinical manifestations may be disproportionate to the extent of white matter involvement. Other organs may frequently be involved. The onset is often in infancy with a neurodegenerative course. The finding of a leukoencephalopathy in a patient with a complex neurologic picture and multisystem involvement should prompt a thorough mitochondrial evaluation.

Brain Diseases↗

PubMed2004

Sulthiame in childhood epilepsy.

BACKGROUND: Sulthiame is a central carbonic anhydrase inhibitor found to be effective for both partial and generalized seizures. It has been in use in some European countries and in Israel for over 30 years. The aim of the present study was to evaluate the efficacy and tolerability of sulthiame in childhood epilepsy by conducting a multicenter, retrospective study of patients who received this drug. METHODS: The charts of 125 consecutive epilepsy patients treated with sulthiame as monotherapy or add-on therapy were reviewed. RESULTS: Twenty-nine out of 39 patients with benign focal epilepsy of childhood became seizure-free. Total seizure control was also achieved in 17 of 42 patients with symptomatic, non-refractory localization-related epilepsy, and in all 10 cases with juvenile myoclonic epilepsy. Complete normalization of the EEG occurred in 13 of 20 patients with benign partial epilepy of childhood. Side-effects were minimal and caused discontinuation of treatment in only seven children. CONCLUSION: The high tolerability, efficacy, convenience of use and low cost suggest that sulthiame should become a first line drug in the benign partial epilepsies of childhood and juvenile myoclonic epilepsy. It also has a role as add-on treatment in other partial and myoclonic epilepsies.

Adolescent↗

PubMed2004

Pathological laughter as a symptom of midbrain infarction.

Pathological laughter is an uncommon symptom usually caused by bilateral, diffuse cerebral lesions. It has rarely been reported in association with isolated cerebral lesions. Midbrain involvement causing pathological laughter is extremely unusual. We describe three patients who developed pathological laughter after midbrain and pontine-midbrain infarction. In two patients a small infarction in the left paramedian midbrain was detected, whereas the third one sustained a massive bilateral pontine infarction extending to the midbrain. Laughter heralded stroke by one day in one patient and occurred as a delayed phenomenon three months after stroke in another. Pathological laughter ceased within a few days in two patients and was still present at a two year follow-up in the patient with delayed-onset laughter. Pathological laughter can herald midbrain infarction or follow stroke either shortly after onset of symptoms or as a delayed phenomenon. Furthermore, small unilateral midbrain infarctions can cause this rare complication.

Brain Stem Infarctions↗

PubMed2004

Technetium 99m ethylcysteinate dimer single-photon emission computed tomography (SPECT) during intellectual stress test in children and adolescents with pure versus comorbid attention-deficit hyperactivity disorder (ADHD).

Children and adolescents with the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) diagnosis of attention-deficit hyperactivity disorder (ADHD) can have comorbid conditions such as conduct disorder, oppositional defiant disorder, and obsessive-compulsive disorder (comorbid type). The purpose of our study was to compare the pattern of regional cerebral perfusion in these two groups of children with ADHD during a computerized performance test. Nineteen children and adolescents were enrolled in the study. Seven boys and one girl with pure ADHD (group 1: mean age 12 years, range 9-16 years) and nine boys and two girls with comorbid ADHD (group 2: mean age 11 years, range 8-16 years) were studied by single-photon emission computed tomography (SPECT). The patients were not receiving any medication for at least 48 hours prior to the study. All patients were injected with 99mTc-ethylcysteinate dimer while doing a computerized performance test. Nine age-matched control children (five boys and four girls, mean age 12 years, range 9-17 years) with a normal brain SPECT served as controls. All patients in group 2 showed significantly decreased perfusion in the temporal lobes (P < .005). Five patients had decreased frontal lobe perfusion. Additionally, two patients in group 2 had decreased perfusion in the basal ganglia (not significant). Four of eight patients in group 1 had decreased frontal lobe perfusion (not significant). In addition, two patients had bilateral temporal lobe abnormalities, whereas two patients had a normal SPECT. Three patients in group 1 also had decreased basal ganglia perfusion. In contrast to previous studies of brain perfusion in ADHD that focused mainly on frontal and prefrontal cortical abnormalities, our study demonstrates that temporal lobe perfusion abnormalities are more common in patients with the comorbid type of ADHD. We postulate that these findings can have therapeutic implications and explain the decreased response to stimulants in this group of patients.

Adolescent↗

PubMed2004

Congenital hydrocephalus and continuous spike wave in slow-wave sleep--a common association?

Early-onset hydrocephalus was identified as the common denominator in 5 of 12 consecutive patients with Landau-Kleffner syndrome or continuous spike wave in slow-wave sleep who presented during the last 6 years. This association seems to be more common than expected, and the course of epileptic disease and outcome differs from that of previous reports. We present the clinical cases and discuss the possible connection between early hydrocephalus and epilepsy, especially continuous spike wave in slow-wave sleep. A retrospective analysis was undertaken of the clinical course and electroencephalographic (EEG) data before and after the development of continuous spike wave in slow-wave sleep in a group of five children with early-onset hydrocephalus identified in three epilepsy clinics in Israel. Landau-Kleffner syndrome or continuous spike wave in slow-wave sleep was identified in 12 patients during 6 years (1995-2000). Five patients had a history of early-onset hydrocephalus. Three patients had ventriculoperitoneal shunts; two of them were never shunted. Patients' seizures and continuous spike wave in slow-wave sleep epileptiform activity was resistant to appropriate anticonvulsant treatment. Pediatric neurologists and neurosurgeons should be aware of the association between continuous spike wave in slow-wave sleep and early-onset hydrocephalus. When a child with hydrocephalus presents with behavioral, cognitive, or motor deterioration, he or she should undergo sleep EEG in addition to investigation of shunt function. Our series demonstrated the presence of continuous spike wave in slow-wave sleep and localization-related epilepsy that did not originate from the shunt site. This group of patients is heterogeneous, and the exact trigger for continuous spike wave in slow-wave sleep development is still unclear.

Age Factors↗

PubMed2004

Should autistic children be evaluated for mitochondrial disorders?

Autism is etiologically heterogeneous; medical conditions are implicated in only a minority of cases, whereas metabolic disorders are even less common. Recently, there have been articles describing the association of autism with mitochondrial abnormalities. We critically review the current literature and conclude that mitochondrial disorders are probably a rare and insignificant cause of pure autism; however, evidence is accumulating that both autosomal recessive and maternally inherited mitochondrial disorders can present with autistic features. Most patients will present with multisystem abnormalities associated with autistic behavior. Finding biochemical or structural mitochondrial abnormalities in an autistic child does not necessarily imply a primary mitochondrial disorder but can also be secondary to technical inaccuracies or another genetic disorder. Clinicians should be careful in diagnosing a mitochondrial disorder in an autistic child because it has important implications for accurate genetic counseling, prognosis, and therapy.

Autistic Disorder↗