[Cerebral vasculitis]. / Vasculitis cerebrales.

INTRODUCTION: Cerebral vasculitis embraces a wide range of conditions that are characterised by involvement of the vessels of the central nervous system (CNS) due to inflammation of their walls, which in turn leads to occlusion or the formation of aneurysms with the ensuing ischaemic-haemorrhagic disorders this produces. DEVELOPMENT: In cases of cerebral vasculitis perhaps only the vessels of the CNS (isolated angiitis of the CNS) are involved, or they may be just another of the affected territories to be found in primary or secondary systemic angiitis (due to infection, collagen diseases, drugs, tumours). Neurological symptoms and lab tests are usually rather unspecific. The latest neuroimaging techniques are more useful, and the gold standard among them is digital angiography, although its sensitivity and specificity are limited. Brain tissue biopsy allows for confirmation of the diagnosis and is the gold standard for the diagnosis of isolated angiitis of CNS. A large group of conditions (which may be metabolic, demyelinating, vascular, infectious, and other peripheral vascular diseases) have similar clinical and imaging features, which makes it necessary to consider the differential diagnosis. CONCLUSIONS: Involvement of the nervous system casts a shadow over the prognosis in most cases of vasculitis and can be severe, as in isolated vasculitis of large vessels or in Takayasu's disease, or more benign, as in isolated vasculitis of small vessels and in other primary vasculitis. Treatment with corticoids and immunosuppressant agents, as well as anticoagulant and/or antiaggregating therapy, must be considered in each particular case according to the clinical condition and the progression of each patient.

[Unusual variants of Guillain-Barré syndrome in infancy]. / Variantes inusuales del síndrome de Guillain-Barré en la infancia.

AIMS: To identify unusual variants within a paediatric population of patients with Guillain-Barré syndrome (GBS), to determine the frequency of their occurrence and to describe their clinical and electrophysiological characteristics. PATIENTS AND METHODS: The medical records of 179 patients diagnosed with GBS were reviewed. Those who strictly satisfied the Asbury criteria were excluded. RESULTS: Twenty patients, with a mean age of 7.6 years at the onset of symptoms, presented the following clinical variants: multiple cranial polyneuropathy (4 cases), Miller Fisher syndrome (MFS) (3 cases), pharyngeal-cervical-brachial palsy (PCBP) (2 cases), combined MFS and PCBP (3 cases), paraparesis (4 cases), palpebral ptosis without ophthalmoplegia (1 case), ophthalmoplegia without ataxia (1 case), paresis of the abducent nerve with paresthesias (1 case), and saltatory (1 case). Albuminocytologic dissociation was reported in 77.8% of patients and neuroconduction with a demyelinating pattern was noted in 75%. Patients progressed favourably in 94.4% of cases. CONCLUSIONS: In our study, 11.2% of a population of children with GBS presented unusual variants and did not meet the criteria established by Asbury et al. Recognising these variants of GBS in patients with complex pictures such as those described here enables therapy to be established quickly. The question remains as to whether these variants represent a clinical response to different antibodies or to a regional susceptibility of the host.

Permanent visual loss after shunt malfunction.

Fourteen (1.8%) of more than 800 children evaluated in a Visually Impaired Program over 10 years became permanently blind during an episode of raised intracranial pressure secondary to shunt malfunction. Visual symptoms and papilledema were recognized in only three children at the onset of blindness. Clinical and radiologic findings suggested that the loss of sight was caused by a lesion in the pregeniculate pathway in nine patients, probably due to ischemia; five children in the postgeniculate group sustained infarcts of the occipital lobes. These cases highlight the importance of parent education and prompt treatment of raised intracranial pressure due to shunt malfunction.

Nerve biopsy in children with severe Guillain-Barré syndrome and inexcitable motor nerves.

The presence of inexcitable motor nerves early in the course of Guillain-Barré syndrome (GBS) identifies a subgroup of patients with more severe disease and delayed recovery. How frequently these electrodiagnostic findings reflect a primary axonal attack ("axonal" GBS) is controversial. We present two children with severe acute GBS, delayed recovery, and residual disability despite early treatment with human immunoglobulin. They had inexcitable motor nerves at days 6 and 7, and profuse fibrillations and positive waves on subsequent studies. Clinically and electrodiagnostically, both children's disease resembled the acute motor-sensory axonal variant of GBS (AMSAN). Sensory and motor nerve biopsies revealed severe macrophage-associated demyelination with axonal degeneration of variable severity. We conclude that clinical and electrodiagnostic features cannot discriminate between the "axonal" and demyelinating GBS. Early and severe demyelination with secondary axonal damage may mimic clinically and electrophysiologically the AMSAN variant of GBS.

Severe Guillain-Barré syndrome in childhood treated with human immune globulin.

Thirteen children with severe Guillain-Barré syndrome were treated with human immune globulin. Patients received a mean total dose of 1.9 gm/kg of human immune globulin for 2 or 5 days. To evaluate the relationship between the response to human immune globulin and electrodiagnostic findings, we compared the clinical outcome of 3 groups of children. The first group consisted of 9 children with electrophysiologic evidence of a mean amplitude of the compound motor action potentials larger than 10% of the lower limit of normal. The second group of 4 children had inexcitable motor nerves. Children in the second group required longer periods to improve one functional grade (mean 67.3 days vs 18.8 days) and to reach grade 2 (219 days vs 32.7 days). Moreover, children in the second group were more disabled after 3 and 6 months, and they all remained with distal atrophy and weakness after 7 months of follow-up. Furthermore, the outcome of children in the second group was no different from that of a historic control of 5 untreated children with severe Guillain-Barré syndrome and similar electrophysiologic findings. Human immune globulin treatment in children with severe Guillain-Barré syndrome is safe, easy to administer, and does not increase the number of relapses. Nevertheless, it does not seem to benefit children with low mean compound motor action potential amplitude.

[Headaches in children and adolescents. An etiopathogenic classification]. / Cefalea en la infancia y adolescencia. Clasificación etiopatogénica.

Headache is one of the most frequent reasons for presenting to Neuropaediatric units. Although in most cases the patient is not suffering from any serious disease, the parents and even the paediatrician do tend to fear that this is indeed the case. Evaluating a patient with headache requires a detailed interview, as well as a careful clinico-neurological examination. From these elements it is basically possible to sort headaches into four large groups: acute, acute-recurrent, chronic non-progressive and chronic progressive. Acute headaches are an emergency and it is therefore necessary to have an algorithm available which can be used regardless of the degree of complexity of the clinical environment in which the patient is being treated. Invasive studies such as a spinal tap and/or neuroradiological studies are often needed. The International Headache Society criteria have been adapted to the juvenile population for the diagnosis of patients suffering from acute-recurrent headaches (migraine). Chronic non-progressive headaches are a group in which prevalence increases with age and is the most frequently observed form of headache in adolescents. Emotional factors, situations involving family and/or social conflict, either alone or in combination, are usually predisposing or triggering factors in this type of headache. Chronic progressive headache is a consequence of some organic disorder. In the search for and treatment of headache we must not forget to calm the pain experienced by the patient.

[Toxic encephalopathies]. / Encefalopatías tóxicas.

INTRODUCTION AND DEVELOPMENT: Due to an increase in the use of industrial products (gases, solvents, pesticides, heavy metals, pharmaceuticals, and so on) living beings are exposed to the effects of many new substances, many of whose possibly toxic effects were not researched sufficiently before being put to use on a massive scale. Owing to their particular physiology, habitat and behaviour, children and teenagers are often a target for these substances. Most of the intoxications present with symptoms and signs of nervous system involvement that are similar to those caused by other diseases. In certain cases, a diagnosis is provided by the setting or witnesses. In other cases, however, first a high degree of suspicion is required and then this is sometimes confirmed by toxicology laboratory studies. CONCLUSIONS: When intoxication is suspected in a child or they need treatment, such patients must visit a toxicological care centre. In spite of the campaigns aimed at preventing intoxications, they are still a common cause of high morbidity and mortality rates among children and teenagers.

[Cerebrovascular disease in childhood and adolescence. Ischaemic cerebral accidents]. / Enfermedad cerebrovascular en la infancia y adolescencia. Accidente isquémico cerebral.

In recent years attention has been drawn to cerebrovascular disease in children and adolescents, since cases are now better detected and hence there has been an apparent increase in their incidence. The traditional risk factors of adult cerebrovascular disease are considered to be unimportant in children and adolescents. In these young patients there are many other more important risk factors, genetic, metabolic and infections, acting alone or in combination. The most important of these are cardiac disorders, prothrombotic states and vascular disorders. There are many imaging techniques available for the investigation of patients with ischaemic symptoms, which permit early diagnosis using non invasive methods. The newer perfusion diffusion MR techniques may play an important part in evaluation and treatment, especially in patients at risk. Most treatment currently available is symptomatic. However, interventionist neuroradiology may in future play an important part in treatment in this age group. Recent studies have shown that the prognosis is not as good as previously thought and half the patients have motor sequelas and a similar number require special schooling.

[Viral encephalitis]. / Encefalitis viral.

Viral infections of the nervous system make up a wide range of disorders with a mainly benign outcome. However, in some cases there is severe, morbimortality. In viral encephalitis there is direct involvement of the brain parenchyma which is seen clinically as reduced consciousness, convulsions and/or focal neurological deficit. The especial attraction of some viruses for particular cells or structures determines the variety of clinical findings. The incidence and frequency of the various agents depends on several factors (geographical location of a certain virus, age and general health of the population concerned, etc.). In areas free of arbovirus the commonest aetiologies are; varicella, herpes simplex, parotiditis and enterovirus. Modern treatment (transplants, chemotherapy) of previously fatal diseases and the AIDS epidemic have increased the number of immunodeficient patients; the population is susceptible to viral infections of the nervous system which are infrequent (e.g. cytomegalovirus, papovavirus) or which follow a different course (e.g. measles, enteroviruses) to that in immunocompetent patients. Specific conditions are reviewed. Improvement in the general health and sanitation of the population, and the universal use and development of new vaccines will significantly reduce the incidence of viral encephalitis. Improved prognosis will be related to the use of modern laboratory techniques which permit early, sensitive, specific diagnosis and the development of antiviral agents.

[Posterior reversible encephalopathy in infancy]. / Encefalopatía posterior reversible en la infancia.

INTRODUCTION: Posterior reversible encephalopathy (PRE) is a radiological clinical syndrome that was initially reported in adults and which is characterised by seizures, headache, visual disorders, decreased awareness and anomalous neuroimages. It is an acute transient disorder. The most frequent causes are arterial hypertension (AHT) and immunosuppressive therapy. AIMS: The aim of this study is to describe the characteristics of PRE in patients of paediatric age. PATIENTS AND METHODS: From a total of 109,267 patients admitted to hospital between 1/1/1999 and 1/8/2002, we reviewed the case histories of seven patients who satisfied PRE criteria. RESULTS: Seven patients presented AHT associated with kidney disease (6) and with an undetermined causation (1). The initial symptoms were vomiting in seven and headaches in five patients, followed by seizures in six cases, which were partial (4), generalised (1), motor status (1). Five of them suffered visual disorders. All of them had decreased awareness and one of them required the assistance of mechanical ventilation. The condition cleared within 3 to 12 days after antihypertensive therapy. The anomalies that showed up in the neuroimaging studies (hypodensities in CAT, hyperintensities in T2 and hypointensities in T1 in MR) revealed the involvement of cortical and parieto occipital cortico subcortical regions asymmetrically. Frontal (2), temporal (2) and cerebellous (1) involvement was also observed. These disorders disappeared in patients from whom control images were obtained. CONCLUSIONS: PRE must be considered in the presence of the symptoms and the anomalous neuroimages described above, when associated with acute AHT. With correct management of arterial hypertension it is possible to clear the neurological symptoms and normalise the neuroimages that confirm this diagnosis.

[Hemiparetic cerebral palsy and startle epilepsy]. / Parálisis cerebral hemiparética y epilepsia del sobresalto.

OBJECTIVES: We analyzed electroclinical features and evolution in nine patients with hemiparetic cerebral palsy associated with SE. PATIENTS AND METHODS: Nine patients with mean age 12.3 years and a follow up from 1 to 11 years were studied, analyzing etiology, neurological examination, psychometric evaluation, age at onset and semiology of epileptic seizures, EEGs and neuro-radiological findings, response to treatment and evolution. RESULTS: Etiologies were: porencephaly in 4 cases, hypoxic-ischemic encephalopathy in 2, bacterial meningitis in 1, herpetic encephalitis in 1 and meningo-encephalitis in the last. All cases had mental retardation. Mean age at onset of epileptic seizures was 4 years. Mean age at onset of startle seizures was 6. The startle seizures were characterized by sudden tonic contractions of the paretic hemibody, provoked by auditory stimulus in 6, somatosensory in 2 and both types of stimulus in 1. Falls were observed in 6 patients. Seizures were daily and always when awake. Unprovoked focal seizures with or without secondary generalization were found in 8 cases, and in 6 they presented previously to the startle seizures. Interictal EEGs showed unilateral spikes in 3, bilateral spikes in 3 and generalized polyspike-wave paroxysms in the other three cases. Ictal EEGs were obtained in 8 of the 9 patients and showed diffuse paroxysms of rhythms 6-11 Hz. Cerebral CT scan and/or MRI revealed extensive unilateral encephalomalacia in 5 and porencephaly in 4. The different antiepileptic schedules were unsuccessful in all cases. Surgery was performed in two patients. They are free of seizures after 1 to 4 years of follow up. CONCLUSION: SE should be considered as a distinctive epileptic syndrome or a particular electro-clinical evolution in patients with a large unilateral brain lesion associated with provoked reflex seizures usually refractory to antiepileptic drugs. Epileptic surgery should be considered.

[Polyneuropathy in critically ill patients: a seldom recognized cause of dependence on mechanical ventilators]. / Polineuropatía del paciente crítico pediátrico: una causa poco reconocida de dependencia al respirador.

INTRODUCTION: Neuromuscular complications, in a critical care unit, are a cause of morbidity in children and prolonged dependence on a mechanical ventilator. Polyneuropathy of the critical patient is such a complication and is seen in patients on mechanical respiratory assistance. OBJECTIVE: To discuss the neurological and electrophysiological clinical findings of polyneuropathy of the critical patient. CLINICAL CASE: We evaluated four patients who initially required mechanical respiratory assistance, three for lung disorders and one for acute encephalopathy, who developed prolonged dependence on mechanical ventilators in the year 1999. In all these patients electromyography showed primary axon nerve disorders with secondary demyelination of all four limbs and phrenic nerve involvement. CONCLUSIONS: Clinical suspicion and use of suitable electrophysiological techniques permits identification of this condition in the severely ill paediatric patient. Better recognition of the condition and investigation of the etiological factors would help to develop suitable measures for prevention and treatment.

[Angelman syndrome: the electroclinical characteristics in 35 patients]. / Sindrome de Angelman: características electroclínicas en 35 pacientes.

AIMS: The purpose of this study is to report on 35 patients with Angelman syndrome (AS) in whom we evaluated the electroclinical characteristics and the progression of their epilepsy. PATIENTS AND METHODS: The following factors were evaluated: sex, family background, neurological examination, age at onset and semiology of the epileptic seizures, EEG, types of epilepsy according to the international classification and response to therapy. We investigated the karyotype, and conducted FISH and methylation tests for AS. RESULTS: The 35 patients had an average follow up time of 5.6 years. Epilepsy was diagnosed in 25 cases, with an average age of onset of 1.6 years. The epileptic syndromes were: epilepsy with myoclonic seizures in 13, of which seven presented a myoclonic state in their history, focal epilepsy in seven, West's syndrome in three, and Lennox Gastaut syndrome in two. Intercritical EEG showed generalised MSW and SW paroxysms in 13, unilateral spikes in seven, hypsarrhythmia in three, generalised fast rhythm paroxysms and slow SW activity in two. Basal electroencephalographic activity was: slow hypervoltage waves with or without inserted spikes situated at the rear in 19, at the front in six, diffuse in six, and normal in four cases. CONCLUSIONS: 71.4% of patients with AS suffered epileptic seizures; epilepsy with myoclonic seizures was the most frequently observed epileptic syndrome and hypervoltage slow wave activity with or without spikes inserted in the posterior quadrants was a characteristic encephalographic pattern. In patients with mental retardation, with or without epilepsy and these electroencephalographic findings, even in the absence of characteristic clinical signs, methylation and FISH analyses for AS should be performed.

Espectro clínico de pacientes con hallazgos histopatológicos y/o moleculares compatibles con enfermedad mitochondrial / Clinical spectrum of patients with histopathological and/or molecular findings compatible with mitochondrial disease

Objetivo: Describir el espectro clínico de pacientes con diagnóstico definitivo de Enfermedad Mitocondrial, y su correlación con hallazgos bioquímicos, neuroimagenológicos, neuropatológicos, y moleculares. Método: Se revisaron las historias clínicas de pacientes con Enfermedad Mitocondrial evaluados durante el período 1990-2011. Resultados: Se incluyeron 41 pacientes, con una edad media inicial de 3,7 años. Identificamos cuatro grupos:1) Síndromes clásicos (65%): a) MELAS del inglés “Mitochondrial encephalomyopathy, lacticacidosis, and stroke-like episodes”, (diez), b) Síndrome de Leigh (diez) c) Síndrome de Kearns –Sayre (cinco), d) PEO del inglés “Progressive External Ophthalmoplegia” plus (OEP plus) (dos), 2) Miopatía: nueve (21,5%) 3) Encefalomiopatías inespecíficas: cinco (12%). Se realizó biopsia muscular en 37 pacientes. Un 70% evidenció fibras rojo rasgadas, cuatro (10,5%) fibras citocromo oxidasa negativas y ocho (14,7%) incremento de la actividad oxidativa subsarcolemal y en la microscopia electrónica alteraciones del tamaño y número de mitocondrias. En 14 se completaron estudios moleculares: Siete presentaron una mutación puntual A3243G en el ADN mitocondrial (MELAS), un paciente una mutación en el ADN mitocondrial A1351G (Síndrome de Leigh) y un paciente una deleción del ADN mitocondrial (OEP plus). Conclusiones: Se pudo corroborar la existencia en nuestro medio de síndromes asociados a patología mitocondrial tradicionalmente reconocidos. Un grupo de pacientes con encefalomiopatías denominadas inespecíficas presentaron un cuadro clínico variable, hallazgos de laboratorio y de imágenes poco orientadores y fue la sospecha de una enfermedad mitocondrial lo que nos llevó a realizar la biopsia que finalmente fue diagnóstica. Es posible que este grupo sea más numeroso y las limitaciones que implica realizar una biopsia muscular se facilite con los estudios moleculares.

[Acute benign ataxia in childhood]. / Ataxia aguda benigna en la infancia.

The patogenesis and etiology of acute ataxia in childhood is not well known. It may occur without previous symptoms or may be the expression of specific infectious diseases. Forty patients hospitalized at the Hospital de Niños de Buenos Aires en 1972-1978, were studied. The neurological manifestations showed an acute onset, being ataxia the main sign, associate to tremor, nystagmus, dysartria, oculo-motor paresia, muscular weakness, and hyporeflexia. Most of the patients (82%) became cured within the first four weeks. It is advisable to establish a follow-up with periodic controls, mainly in those patients in whom an association with previous infectious diseases did not exist to be able to detect an association with degenerative or desmyelinizing diseases.

Krabbe disease in monozygotic triplets.

The authors report an extremely rare case of monozygotic triplets with globoid cell leukodystrophy (Krabbe disease). Born to healthy, non-related, heterozygous parents, all three girls presented with typical signs of beta-galactocerebrosidase deficiency before one year of age and died within the first 41 months of life. The literature is briefly reviewed.

Miastenia gavis ocular en pediatría. Clínica y evolución a largo plazo / Ocular myastenia gravis in children. Clinical features and long - term outcome

Objetivo: Reportar cuadro clínico, patologías asociadas y evolución a largo plazo en pacientes con MGO. Material y Métodos: De 74 pacientes con miastenia gravis juvenil atendidos durante el período 1987-2003, se reportan 29 con MGO. Se incluyeron: a) menores de 16 años con debilidad de músculos extraoculares (MGO), elevador y orbicular de los párpados, durante un período mínimo de 6 meses; b) con una de las siguientes pruebas positivas: prueba farmacológica (PF); prueba de estimulación repetitiva (PER); anticuerpos contra receptor de acetilcolina (ACRA) positivo y/o respuesta a inmunosupresores. Resultados: Edad media de inicio de síntomas: 3,6 años, con una relación mujer/varón 2.2/1. Cuadro clínico inicial: ptosis palpebral 100 por ciento (bilateral 62 por ciento); paresia de MEO 86 por ciento; diplopía 17 por ciento; disminución de la agudeza visual (AV) 27 por ciento; ritmo miasténico 89 por ciento. Estudios complementarios: PF (más)100 por ciento (n=25); PER (más)74 por ciento (n=23) y ACRA (más) 52 por ciento (n=21). Evolución: se incluyeron 21 pacientes con seguimiento mayor a un año (media de 8 años). Tres pacientes tuvieron remisión completa estable (1 espontánea y 2 con corticoides); 8 manifestaciones mínimas (5 con piridostigmina y 3 corticoides) y 10 persistencia clínica (3 con piridostigmina y 7 corticoides). Tres (14 por ciento) casos presentaron recurrencias. Cuatro niños quedaron con marcada disminución de la AV y 4 con mirada congelada. Enfermedad asociada: patologías tiroideas (38 por ciento); diabetes (5 por ciento). Conclusiónes: Pacientes con MGO tienen características propias que difieren de las formas generalizadas. Estas son: inicio precoz, mayor positividad de PF, pero menor de la PER y ACRA; elevado porcentaje de pacientes que persisten sintomáticos y con secuelas visuales. Nuevas modalidades terapéuticas deberían ser intentadas, teniendo en cuenta los efectos colaterales de los inmunosupresores a una edad temprana y el riesgo de sec...