Clinical features and management of hereditary spastic paraplegia / Aspectos clinicos e manejo das paraplegias espasticas hereditarias

Hereditary spastic paraplegia (HSP) is a group of genetically-determined disorders characterized by progressive spasticity and weakness of lower limbs. An apparently sporadic case of adult-onset spastic paraplegia is a frequent clinical problem and a significant proportion of cases are likely to be of genetic origin. HSP is clinically divided into pure and complicated forms. The later present with a wide range of additional neurological and systemic features. To date, there are up to 60 genetic subtypes described. All modes of monogenic inheritance have been described: autosomal dominant, autosomal recessive, X-linked and mitochondrial traits. Recent advances point to abnormal axonal transport as a key mechanism leading to the degeneration of the long motor neuron axons in the central nervous system in HSP. In this review we aim to address recent advances in the field, placing emphasis on key diagnostic features that will help practicing neurologists to identify and manage these conditions.

Paraplegias espásticas hereditárias (PEH) constituem um grupo de desordens geneticamente determinadas caracterizadas por espasticidade e paraparesia de progressão insidiosa. Paraplegia espástica aparentemente esporádica de início no adulto constitui problema frequente na prática neurológica. Evidências recentes sugerem que uma proporção significativa destes casos é geneticamente determinada. O grupo das PEH é dividido clinicamente em formas puras e complicadas de acordo com a concomitância de outras manifestações clinicas e neurológicas. Até o momento 60 tipos genéticos foram identificados. Todos os modos de herança monogênica já foram descritos: autossômica dominante, autossômica recessiva, ligada ao X e mitocondrial. Avanços recentes indicam que alterações do transporte axonal estão implicadas na degeneração dos longos axônios motores no sistema nervoso central na PEH. Nesta revisão abordamos recentes avanços na área com ênfase nos aspectos clínicos chave que ajudam o neurologista geral no diagnóstico e manejo correto deste grupo de doenças.

Split-hand/feet malformation in three tamilian families and review of the reports from India.

Split‑hand/foot malformation (SHFM) is a rare condition which can be either syndromic or nonsyndromic. We report three unrelated pedigrees, one with autosomal dominant (AD) inheritance and the other two with autosomal recessive (AR) pattern. We also briefly review the published reports from India.

Síndrome de Ellis Van Creveld: caso clínico / Ellis Van Creveld syndrome: case report

El Síndrome de Ellis Van Creveld es poco frecuente, hereditario de carácter autosómico recesivo no habiendo predilección por sexo. Se caracteriza por acortamiento acromesomélico, polidactilia postaxial bilateral de manos, condrodisplasia de huesos largos y displasia ectodérmica de uñas y dientes. El conocimiento de la misma es imperativo para un diagnóstico temprano y manejo multidisciplinario oportuno que permita una mejor calidad de vida de estos pacientes.

The Ellis Van Creveld syndrome is rare, hereditary autosomal recessive, without no sex predilection. It is characterized by short-limbed dwarfism, bilateral postaxial hand polydactyl, chondrodysplasia of long bones and ectodermic dysplasia affecting fingernails and teeth. The knowledge of it is essential for early diagnosis and appropriate multidisciplinary management that allows a better quality of life for these patients.

Medidas de audição de pais de indivíduos com deficiência auditiva de herança autossômica recessiva / Auditory measurements in parents of individuals with autosomal recessive hearing loss

TEMA: avaliação audiológica de pais de indivíduos com perda auditiva de herança autossômica recessiva. OBJETIVO: estudar o perfil audiológico de pais de indivíduos com perda auditiva, de herança autossômica recessiva, inferida pela história familial ou por testes moleculares que detectaram mutação no gene GJB2, responsável por codificar a Conexina 26. MÉTODO: 36 indivíduos entre 30 e 60 anos foram avaliados e divididos em dois grupos: grupo controle, sem queixas auditivas e sem história familiar de deficiência auditiva, e grupo de estudos composto por pais heterozigotos em relação a genes de surdez de herança autossômica recessiva inespecífica ou portadores heterozigotos de mutação no gene da Conexina 26. Todos foram submetidos à audiometria tonal liminar (0,25kHz a 8), audiometria de altas freqüências (9kHz a 20) e emissões otoacústicas produtos de distorção (EOAPD). RESULTADOS: houve diferenças significativas na amplitude das EOAPD nas freqüências 1001 e 1501Hz entre os grupos, sendo maior a amplitude no grupo controle. Não houve diferença significativa entre os grupos para os limiares tonais de 0,25 a 20KHz. CONCLUSÃO: as EOAPD foram mais eficazes, em comparação com a audiometria tonal liminar, para detectar diferenças auditivas entre os grupos. Mais pesquisas são necessárias para verificar a confiabilidade destes dados.

BACKGROUND: audiological evaluation of parents of individuals with autosomal recessive hearing loss. AIM: to study the audiological profile of parents of individuals with autosomal recessive hearing loss, inferred by family history or by molecular tests that detected heterozygous mutations in the GJB2 gene. This gene codes Connexin 26. METHOD: participants were 36 subjects, ranging between 30 and 60 years, who were divided into two groups: a control group composed by individuals without auditory complaints and without family history of hearing loss, and a research group composed by heterozygous parents of individuals with autosomal recessive hearing loss or heterozygous for connexin 26 mutations. All subjects underwent pure tone audiometry (0,25 to 8kHz), high frequencies audiometry (9 to 20kHz) and distortion product otoacoustic emissions (DPOAE). RESULTS: there were significant differences between the groups when considering the amplitude of DPOAE in the frequencies of 1001 and 1501Hz. Amplitude was higher in the control group. There was no significant difference between the groups for pure tone thresholds from 0.25 to 20KHz. CONCLUSION: the DPOAE were more effective, in comparison to the pure tone audiometry, to detect auditory differences between the groups. More studies of this type are necessary to confirm the observed results.

Autosomal recessive ataxias: 20 types, and counting / Ataxias autossômicas recessivas: 20 tipos e muito mais

More than 140 years after the first description of Friedreich ataxia, autosomal recessive ataxias have become one of the more complex fields in Neurogenetics. Currently this group of diseases contains more than 20 clinical entities and an even larger number of associated genes. Some disorders are very rare, restricted to isolated populations, and others are found worldwide. An expressive number of recessive ataxias are treatable, and responsibility for an accurate diagnosis is high. The purpose of this review is to update the practitioner on clinical and pathophysiological aspects of these disorders and to present an algorithm to guide the diagnosis.

Mais de 140 anos após a primeira descrição da ataxia de Friedreich, as ataxias autossômicas recessivas se transformaram em um dos mais complexos campos da Neurogenética. Atualmente, este grupo de doenças é composto por mais de 20 entidades clínicas e possui um número ainda maior de genes associados. Algumas doenças são muito raras, tendo sido observadas apenas em populações isoladas, enquanto que outras são encontradas no mundo todo. Um número expressivo de ataxias é tratável, e a responsabilidade em se fazer um diagnóstico correto é alta. A finalidade desta revisão é a de atualizar o neurologista a respeito dos principais aspectos clínicos e fisiopatológicos destas doenças e de apresentar um algoritmo para auxiliar a sua investigação e o seu diagnóstico.

Carbonic anhydrase II deficiency: A novel mutation.

Carbonic anhydrase II (CA II) deficiency is an extremely rare autosomal recessive disorder, characterised by a triad of osteopetrosis, renal tubular acidosis and cerebral calcifications. A 12-year-old boy with classical features of CA II deficiency is reported who was found to be homozygous for the mutation in CA II gene and parents were heterozygous for the same mutation .To the best of our knowledge this is the first case report of mutation proven CA II deficiency from India.

A novel missense mutation p. L76P in the GJB2 gene causing nonsyndromic recessive deafness in a Brazilian family

Mutations in the GJB2 gene, encoding connexin 26 (Cx26), are a major cause of nonsyndromic recessive hearing loss in many countries. We report here on a novel point mutation in GJB2, p.L76P (c.227C>T), in compound heterozygosity with a c.35delG mutation, in two Brazilian sibs, one presenting mild and the other profound nonsyndromic neurosensorial hearing impairment. Their father, who carried a wild-type allele and a p.L76P mutation, had normal hearing. The mutation leads to the substitution of leucine (L) by proline (P) at residue 76, an evolutionarily conserved position in Cx26 as well as in other connexins. This mutation is predicted to affect the first extracellular domain (EC1) or the second transmembrane domain (TM2). EC1 is important for connexon-connexon interaction and for the control of channel voltage gating. The segregation of the c.227C>T (p.L76P) mutation together with c.35delG in this family indicates a recessive mode of inheritance. The association between the p.L76P mutation and hearing impairment is further supported by its absence in a normal hearing control group of 100 individuals, 50 European-Brazilians and 50 African-Brazilians.

Autosomal recessive type I lissencephaly.

Lissencephaly (LIS) is a brain malformation manifested by a smooth cerebral surface, thickened cortical mantle and microscopic evidence of incomplete neuronal migration, excluding polymicrogyria and other cortical dysplasias. It is important to consider LIS in the diagnosis of developmental delay as many patients may be diagnosed as cerebral palsy. It may have familial occurrence and can occur in sibs of same family often leading to a diagnostic problem. Several lissencephaly syndromes have been described. Here a familial syndrome of lissencephaly is reported. Autosomal recessive inheritance is suggested by recurrence in sibs within the same family, but germ cell mosaicism for a dominant mutation cannot be excluded.

Clinical and Genetic Analysis of Korean Patients with Miyoshi Myopathy: Identification of Three Novel Mutations in the DYSF Gene

Miyoshi myopathy (MM) is an autosomal recessive distal muscular dystrophy caused by mutations in the dysferlin gene (DYSF) on chromosome 2p13. Although MM patients and their mutations in the DYSF gene have been found from all over the world, there is only one report of genetically confirmed case of MM in Korea. Recently, we encountered three unrelated Korean patients with MM and two of them have previously been considered as having a type of inflammatory myopathy. The clinical and laboratory evaluation showed typical features of muscle involvement in MM in all patients but one patient initially had moderate proximal muscle involvement and another showed incomplete quadriparesis with rapid progression. Direct sequencing analysis of the DYSF gene revealed that each patient had compound heterozygous mutations (Gln832X and Trp992Arg, Gln832X and Trp999Cys, and Lys1103X and Ile1401HisfsX8, respectively) among which three were novel. Although MM has been thought to be quite rare in Korea, it should be considered in a differential diagnosis of patients exhibiting distal myopathy.

Missense mutation R121W in the Norrie disease gene in Kuwaiti Bedouin family

Herein, we describe the molecular defects in the Norrie disease [ND] gene in a Kuwaiti Bedouin family with three affected sibs. Norrie disease is a rare X-linked recessive disorder, characterized by congenital blindness, malformed retina, psychomotor delay and deafness in a proportion of patients. We analyzed the genomic DNA through polymerase chain reaction [PCR] and restriction fragment length polymorphism [PCR-RFLP] approach. We have found the presence of R121W mutation within exon 3. We have identified a single base pair substitution [C>T] mutation of ND gene

Profile of major congenital malformations in neonates in Al-Jahra region of Kuwait

We investigated major congenital abnormalities in babies born in Al Jahra Hospital, Kuwait from January 2000 to December 2001. Of 7739 live and still births born over this period, 97 babies had major congenital malformations [12.5/1000 births]: 49 [50.6%] babies had multiple system malformations, while 48 [49.4%] had single system anomalies. Of the 49 babies with multiple malformations, 21 [42.8%] had recognized syndromes, most of which were autosomal recessive and 17 had chromosomal aberrations. Isolated systems anomalies included central nervous system [12 cases], cardiovascular system [9 cases], skeletal system [7 cases] and gastrointestinal system [6 cases]. Of the parents, 68% were consanguineous. Genetic factors were implicated in 79% of cases. Genetic services need to be provided as an effective means for the prevention of these disorders

Papillon-Lefevre syndrome: a report of two cases.

Papillon-Lefevre Syndrome (PLS) is an inherited autosomal recessive disorder presenting with Palmar plantar Keratoderma and Juvenile Periodontitis leading to early loss of both the dentitions. Two cases of PLS in a family with a history of consanguineous descent are presented.

Roberts-SC phocomelia syndrome.

A severely growth retarded baby was born at 38 weeks gestation. He had multiple craniofacial anomalies, microbrachycephaly, phocomelia in the upper limbs and renal cysts visible on ultrasound. He died of recurrent apneas. The autopsy showed left sided multicystic dysplastic kidney and absence of one testis. Cytogenetic studies did not reveal any abnormality. The phenotypic features match those described in the Roberts-SC phocomelia syndrome. A literature review revealed that 50% of these patients have chromosomal defects and antenatal detection is possible on ultrasound and by chromosome analysis of the amniocytes.

Mandibulo-acral dysplasia: Indian patient with severe bony changes.

We report an Indian patient with mandibulo-acral dysplasia. This patient had absence of spinous processes of 4th and 5th cervical vertebrae and very severe bony changes but no loss of teeth.