Impaired glucose transport across the blood brain barrier results in Glut 1 deficiency syndrome (Glut 1 DS, OMIM 606777), characterized by infantile se izures, developmental delay, acquired microcephaly, spastic...Impaired glucose transport across the blood brain barrier results in Glut 1 deficiency syndrome (Glut 1 DS, OMIM 606777), characterized by infantile se izures, developmental delay, acquired microcephaly, spasticity, ataxia, and hypo glycorrhachia. We studied 16 new Glut 1 deficiency syndrome patients focusing on clinical and laboratory features, molecular genetics, genotype phenotype co rrelation, and treatment. These patients were classified phenotypically into thr ee groups. The mean cerebrospinal fluid glucose concentration was 33.1 ± 4.9mg/ dl equal to 37% of the simultaneous blood glucose concentration. The mean cere brospinal fluid lactate concentration was 1.0 ± 0.3mM, which was less than the normal mean value of 1.63mM. The mean Vmax for the 3 O methyl D glucose uptake into erythrocytes was 996 fmol/106 red blood cells per second, significan tly less (54 ± 11% ; t test, p < 0.05) than the mean control value of 1,847. The mean Km value for the patient group (1.4 ± 0.5mM) was similar to the contro l group (1.7 ± 0.5mM; t test, p >0.05). We identified 16 rearrangements, includ ing seven missense, one nonsense, one insertion, and seven deletion mutations. F ourteen were novel mutations. There were no obvious correlations between phenoty pe, genotype, or biochemical measures. The ketogenic diet produced good seizure control.展开更多
文摘Impaired glucose transport across the blood brain barrier results in Glut 1 deficiency syndrome (Glut 1 DS, OMIM 606777), characterized by infantile se izures, developmental delay, acquired microcephaly, spasticity, ataxia, and hypo glycorrhachia. We studied 16 new Glut 1 deficiency syndrome patients focusing on clinical and laboratory features, molecular genetics, genotype phenotype co rrelation, and treatment. These patients were classified phenotypically into thr ee groups. The mean cerebrospinal fluid glucose concentration was 33.1 ± 4.9mg/ dl equal to 37% of the simultaneous blood glucose concentration. The mean cere brospinal fluid lactate concentration was 1.0 ± 0.3mM, which was less than the normal mean value of 1.63mM. The mean Vmax for the 3 O methyl D glucose uptake into erythrocytes was 996 fmol/106 red blood cells per second, significan tly less (54 ± 11% ; t test, p < 0.05) than the mean control value of 1,847. The mean Km value for the patient group (1.4 ± 0.5mM) was similar to the contro l group (1.7 ± 0.5mM; t test, p >0.05). We identified 16 rearrangements, includ ing seven missense, one nonsense, one insertion, and seven deletion mutations. F ourteen were novel mutations. There were no obvious correlations between phenoty pe, genotype, or biochemical measures. The ketogenic diet produced good seizure control.
