Ataxia crónica en pediatría / [Chronic ataxia in childhood].

Chronic ataxias are an heterogeneous group of disorders that affect the child at different ages. Thus, the congenital forms, generally non progressive are observed from first months of life and are expressed by hypotonia and motor delay long before the ataxia became evident. The cerebral magnetic resonance images (MRI) may be diagnostic in some pictures like Joubert syndrome. The group of progressive hereditary ataxias, usually begin after the infant period. The clinical signs are gait instability and ocular apraxia that can be associated with oculocutaneous telangiectasias (ataxia-telangiesctasia) or with sensory neuropathy (Friedreich ataxia). In this review are briefly described congenital ataxias and in more detailed form the progressive hereditary ataxias autosomal recessive, autosomal dominants and mitochondrials. The importance of genetic study is emphasized, because it is the key to obtain the diagnosis in the majority of these diseases. Although now there are no treatments for the majority of progressive hereditary ataxias, some they have like Refsum disease, vitamine E deficiency, Coenzyme Q10 deficiency and others, thus the diagnosis in these cases is even more important. At present the diagnosis of childhood hereditary ataxia not yet treatable is fundamental to obtain suitable handling, determine a precise outcome and to give to the family an opportune genetic counseling.

Predictive Capability of Anorectal Physiologic Tests for Unfavorable Outcomes Following Biofeedback Therapy in Dyssynergic Defecation

The purpose of this study is to evaluate the predictive capability of anorectal physiologic tests for unfavorable outcomes prior to the initiation of biofeedback therapy in patients with dyssynergic defecation. We analyzed a total of 80 consecutive patients who received biofeedback therapy for chronic idiopathic functional constipation with dyssynergic defecation. After classifying the patients into two groups (responders and non-responders), univariate and multivariate analyses were performed to determine the predictors associated with the responsiveness to biofeedback therapy. Of the 80 patients, 63 (78.7%) responded to biofeedback therapy and 17 (21.3%) did not. On univariate analysis, the inability to evacuate an intrarectal balloon (P=0.028), higher rectal volume for first, urgent, and maximal sensation (P=0.023, P=0.008, P=0.007, respectively), and increased anorectal angle during squeeze (P=0.020) were associated with poor outcomes. On multivariate analysis, the inability to evacuate an intrarectal balloon (P=0.018) and increased anorectal angle during squeeze (P=0.029) were both found to be independently associated with a lack of response to biofeedback therapy. Our data show that the two anorectal physiologic test factors are associated with poor response to biofeedback therapy for patients with dyssynergic defecation. These findings may assist physicians in predicting the responsiveness to therapy for this patient population.

Frequency of FMR1 premutation in individuals with ataxia and/or tremor and/or parkinsonism

A late onset neurological syndrome in carriers of premutation in FMR1 gene was recently described. The condition was named fragile-X-associated tremor/ataxia syndrome (FXTAS) and includes intentional tremor, cerebellar ataxia, parkinsonism, and cognitive deficit. We ascertained the contribution of FMR1 premutation to the phenotypes ataxia, tremor and/or parkinsonism. Sixty-six men over 45 years old presenting these symptoms, isolated or combined, were tested. Also, 74 normal men, randomly chosen in the population, formed the control group. In the patient group, no premutation carrier was found, which is in agreement with other observed frequencies reported elsewhere (0-5% variation). No significant differences were found when comparing gray zone allele frequencies among target and control groups. The FXTAS contribution in patients with phenotypic manifestations of FXTAS was 15/748 (2%). The presence of gray zone alleles is not correlated with FXTAS occurrence.

Síndrome de Miller Fisher: presentación de un caso y revisión de la literatura / Miller-Fisher Syndrome: case report and review of the literature

El síndrome de Miller-Fisher se integra por la tríada arreflexia, ataxia y oftalmoplegía, el cual queda englobado entre las enfermedades desmielinizantes. En sus fases iniciales afecta fundamentalmente a los nervios craneales, por lo que originalmente se consideró como una variante del síndrome de Guillain.Barré. A partir de 1956, se ha considerado como una entidad independiente debido a que involucra el sistema nervioso central. Se presenta el caso de un hombre en la octava década de la vida que ingresó a nuestro Hospital por presentar súbitamente ptosis palpebral bilateral, disartria y disfagia a sólidos. El paciente presentó una evolución rápidamente progresiva manifestada por limitación de los movimientos de las cuatro extremidades y por dificultad respiratoria que hizo necesaria la intubación ortotraqueal y asistencia mecánica ventilatoria. Dada la rapidez de la evolución, se decidió utilizar plasmaféresis; esta medida mejoró el estado respiratorio del paciente, pero no modificó sus condiciones neurológicas. Se presenta una revisión de la literatura relacionada con esta entidad