Biomedical subjects

S C Sousa

Publications and source records attributed to S C Sousa.

3 recordsLinked to original sources

PubMed2002

Clinical and genetic heterogeneity in familial temporal lobe epilepsy.

PURPOSE: Familial forms of temporal lobe epilepsy have been described recently. A locus on ch 10q has been linked to partial epilepsy with auditory symptoms. We investigated the proportion of families segregating temporal lobe epilepsy (TLE) linked to ch 10q and sought to establish genotype-phenotype correlations. METHODS: We studied 15 unrelated families segregating TLE. A total of 153 individuals, including 79 patients, were analyzed in this study. Family members were genotyped for four polymorphic dinucleotide repeat markers: D10S185, D10S574, D10S577, and D10S192, which flank the 15-cM candidate interval on ch 10q. Two-point lod scores were calculated for each family separately. RESULTS: Fourteen of our families had ictal semiology of mesial temporal onset of seizures and magnetic resonance imaging (MRI) abnormalities in the mesial structures; only one family, with seven affected individuals, reported auditory symptoms and had normal MRIs. Pedigree analysis showed an autosomal dominant transmission with 0.75 penetrance. Only two families had informative lod scores. A large family, with 22 affected individuals segregating mesial TLE, had negative lod scores for all four markers genotyped. The lod scores were significantly negative (less than -2.00) up to 0.05 for D10S185, 0.10 for D10S574, 0.25 for D10S577, and 0.15 for D10S192. The single family with auditory symptoms had positive lod scores for all markers genotyped, with a Z max of 1.52 at 0.0 for D10S574. CONCLUSIONS: We identified two different clinical groups of families segregating TLE. Most families identified in this study had mesial TLE. Only one single family segregating lateral TLE was found. We significantly excluded linkage between familial mesial TLE and the locus on ch 10q. In addition, we showed evidence for linkage between one family with lateral TLE and markers on ch 10q. This is strong evidence for clinical and genetic heterogeneity among familial forms of TLE.

Chromosome Segregation↗

PubMed2001

Seizure outcome and hippocampal atrophy in familial mesial temporal lobe epilepsy.

OBJECTIVE: To describe the clinical, genetic and MR characteristics of patients with familial mesial temporal lobe epilepsy (MTLE). DESIGN/METHODS: The familial occurrence of MTLE was identified by a systematic search of family history of seizures in patients followed in the authors' epilepsy clinic. All probands and, whenever possible, other affected family members underwent EEG and MR investigations. RESULTS: Twenty-two unrelated families with at least two individuals with MTLE were identified by clinical and EEG findings. Ninety-eight individuals with history of seizures were evaluated. Sixty-eight patients fulfilled the diagnostic criteria for MTLE. MRI was performed in 84 patients, and showed hippocampal atrophy with increased T2 signal in 48 (57%). The distribution of hippocampal atrophy according to the seizure outcome groups was 6 of 13 patients (46%) with seizure remission, 16 of 31 (51%) with good seizure control under medication, and all 16 patients with refractory MTLE. Hippocampal atrophy was found also in patients that did not fulfill the criteria for MTLE: 3 of 10 (30%) patients with febrile seizure alone, 6 of 10 (60%) patients with recurrent generalized tonic-clonic seizures, and 1 of 4 (25%) patients with a single partial seizure. CONCLUSION: Familial MTLE is a clinically heterogeneous syndrome. Hippocampal atrophy was observed in 57% of patients, including those with benign course or seizure remission, indicating that the relationship between hippocampal atrophy and severity of epilepsy might be more complex than previously suspected. In addition, these findings indicate the presence of a strong genetic component determining the development of mesial temporal sclerosis in these families.

Adolescent↗

PubMed2000

[Familial partial epilepsies].

OBJECTIVE: To investigate the clinical and genetic characteristics of familial partial epilepsies. METHOD: Family history of seizures was questioned in all patients followed in our epilepsy clinics, from October 1997 to December 1998. Those with positive family history were further investigated and detailed pedigrees were obtained. All possibly affected individuals available underwent clinical evaluation. Seizures and epilepsy syndromes were classified according to the ILAE recommendations. Whenever possible, EEG and MRI were performed. RESULTS: Positive family history was identified in 32 unrelated patients. A total of 213 possibly affected individuals were identified, 161 of whom have been evaluated. The number of affected subjects per family ranged from two to 23. Temporal lobe epilepsy (TLE) was identified in 22 families (68%), frontal lobe epilepsy in one family (3%), partial epilepsy with centrotemporal spikes in five families (15%), and other benign partial epilepsies of childhood in four families (12%). Most of the affected individuals in the TLE families (69%) had clinical and/or EEG characteristics of typical TLE. However, the severity of epilepsy was variable, with 76% of patients with spontaneous seizure remission or good control with medication and 24% with refractory seizures, including 7 patients that underwent surgical treatment. In the other 10 families, we identified 39 possibly affected subjects, 23 of whom were evaluated. All had good seizure control (with or without medication) except for one patient with frontal lobe epilepsy. Pedigree analysis suggested autosomal dominant inheritance with incomplete penetrance in all families. CONCLUSION: Family history of seizures is frequent among patients with partial epilepsies. The majority of our families had TLE and its expression was not different from that observed in sporadic cases. The identification of genes involved in partial epilepsies may be usefull in classification of syndromes, to stablish prognosis and optimal treatment.

Adolescent↗