Vestibular Syndromes in Childhood and Adolescence.

Introduction The prevalence of vestibular disorders in childhood ranges from 0.4% to 15%; they may be the result of several factors, but most of the time it's an episodic vestibular syndrome related to migraine equivalents. Objective To evaluate the diagnostic and therapeutic aspects of children with vestibular signs and symptoms. Methods The present cross-sectional study evaluated data from the records of patients treated in an outpatient pediatric neurotology clinic over a 10-year period. These data included sociodemographic and clinical variables, results of complementary examinations, the treatment provided, and the clinical evolution. Results The sample was composed of 117 patients, with 54.7% of female subjects with a mean age of 10 years. The most prevalent diagnosis was benign paroxysmal vertigo of childhood (BPVC) (41.9%), followed by vestibular migraine (16.2%). The most prevalent complaint was vertigo (53.9% of the cases). Most patients (66.7%) had inadequate eating habits. Improvement of symptoms was observed in 40.4% of the patients treated with dietary guidance alone. In 80% of the cases, dietary counseling in combination with vestibular rehabilitation therapy achieved therapeutic success without the need of a drug treatment. Conclusion The predominant diagnosis was of BPVC, and its close relationship with the personal and family history of migraine, its benign evolution, and the importance of dietary guidance and vestibular rehabilitation for therapeutic success were observed.

The Relationship between the Etiology of Profound Prelingual Sensorineural Hearing Loss and the Results of Vestibular-Evoked Myogenic Potentials

Abstract Introduction Cervical vestibular-evoked myogenic potentials (cVEMPs) are biphasic, short latency potentials, which represent the inhibition of the contraction of the sternocleidomastoid muscle (SCM) mediated by the saccule, the inferior vestibular nerve, the vestibular nuclei and the medial vestibular spinal tract. Objective To evaluate the response of cVEMPs in individuals with profound prelingual bilateral cochlear hearing loss. Methods A prospective case-control study. A total of 64 volunteers, divided into a study group (31 patients with profound prelingual sensorineural hearing loss) and a control group (33 subjectsmatched for age and gender with psychoacoustic thresholds of ≤ 25 dB HL between 500 and 8,000 Hz) were submitted to the cVEMP exam. The causes of hearing loss were grouped by etiology and the involved period. Results The subjects of the study group aremore likely to present changes in cVEMPs compared to the control group (35.5% versus 6.1% respectively; p = 0.003), with an odds ratio (OR) of 8.52 (p = 0.009). Itmeans that they had 8.52-fold higher propensity of presenting altered cVEMP results. There were no statistically significant differences between the latencies, the interamplitude and the asymmetry index. Regarding the etiology, there was a statistically significant difference when the cause was infectious, with an OR of 15.50 (p = 0.005), and when the impairment occurred in the prenatal period, with an OR of 9.86 (p = 0.009). Conclusion The present study showed abnormalities in the sacculocolic pathway in a considerable portion of individuals with profound prelingual sensorineural hearing loss due to infectious and congenital causes, as revealed by the cVEMP results. (AU)

The Relationship between the Etiology of Profound Prelingual Sensorineural Hearing Loss and the Results of Vestibular-Evoked Myogenic Potentials.

Introduction Cervical vestibular-evoked myogenic potentials (cVEMPs) are biphasic, short latency potentials, which represent the inhibition of the contraction of the sternocleidomastoid muscle (SCM) mediated by the saccule, the inferior vestibular nerve, the vestibular nuclei and the medial vestibular spinal tract. Objective To evaluate the response of cVEMPs in individuals with profound prelingual bilateral cochlear hearing loss. Methods A prospective case-control study. A total of 64 volunteers, divided into a study group (31 patients with profound prelingual sensorineural hearing loss) and a control group (33 subjects matched for age and gender with psychoacoustic thresholds of ≤ 25 dB HL between 500 and 8,000 Hz) were submitted to the cVEMP exam. The causes of hearing loss were grouped by etiology and the involved period. Results The subjects of the study group are more likely to present changes in cVEMPs compared to the control group (35.5% versus 6.1% respectively; p = 0.003), with an odds ratio (OR) of 8.52 ( p = 0.009). It means that they had 8.52-fold higher propensity of presenting altered cVEMP results. There were no statistically significant differences between the latencies, the interamplitude and the asymmetry index. Regarding the etiology, there was a statistically significant difference when the cause was infectious, with an OR of 15.50 ( p = 0.005), and when the impairment occurred in the prenatal period, with an OR of 9.86 ( p = 0.009). Conclusion The present study showed abnormalities in the sacculocolic pathway in a considerable portion of individuals with profound prelingual sensorineural hearing loss due to infectious and congenital causes, as revealed by the cVEMP results.

Spectrum of MMACHC mutations in Italian and Portuguese patients with combined methylmalonic aciduria and homocystinuria, cblC type.

Methylmalonic aciduria (MMA) and homocystinuria, cblC type (MIM 277400) is the most frequent inborn error of vitamin B(12). The recent identification of the disease gene, MMACHC, has permitted preliminary genotype-phenotype correlations. We studied 24 Italian and 17 Portuguese patients with cblC defect to illustrate the spectrum of mutations in a southern European population and discuss the impact that mutation identification has on routine diagnostic procedures. Since the metabolic defect raises the serum levels of homocysteine, we also tested if variants in MTHFR-playing a key role in homocysteine remethylation pathway-could act as genetic modifier in cblC defect. We found that the c.271dupA (accounting for 55% of the MMACH alleles in our cohort) followed by c.394C>T (16%) and c.331C>T (9%) were the most frequent mutations. In our study we also identified a novel mutation (c.544T>C). On the other hand, the MTHFR genotype did not appear to influence age at onset, the clinical phenotype and outcome of patients with cblC defect. This study shows that mutation screening for the most common MMACH mutations occurring in early-onset forms (c.271dupA and c.331C>T) seems to have a high diagnostic yield in a southern European population with cblC defect. Although the identification of the gene defect per se does not predict completely time and severity of disease appearance, our data corroborate the importance of a molecular testing to offer accurate prenatal diagnosis to couples at high risk of having affected children.