1/162. Glycogen storage disease type 1a in three siblings with the G270V mutation. Glycogen storage disease type 1a (von Gierke disease, GSD1a) is caused by the deficiency of microsomal glucose-6-phosphatase (G6Pase) activity. The cloning of G6Pase cDNA and characterization of the human G6Pase gene enabled the identification of the mutations causing GSD1a. Here we report on the clinical and biochemical features of three GSD1a siblings of a Muslin Arab family with a G270V mutation. Two older patients presented with an unusually mild clinical and biochemical course. ( info) |
2/162. Case report: Hepatocellular carcinoma in type 1a glycogen storage disease with identification of a glucose-6-phosphatase gene mutation in one family. A 40-year-old man with glycogen storage disease type 1a (von Gierke disease, GSD1a) developed hepatocellular carcinoma (HCC). Cold single-strand conformation polymorphism (SSCP) with 12% glycerol identified the G727T mutation in the glucose-6-phosphatase (G6Pase) gene, which has been reported to be the most common mutation in Japanese GSD1a patients. This case report is the first documentation of HCC in a case with G727T mutation. Given the prevalence of HCC in GSD1a with various germline mutations, analysis is needed to confirm that the germline mutation in this case is really related to hepatocarcinogenesis. dna analysis of the family pedigree of this case, revealed three individuals with GSD1a and seven heterozygous carriers of the G727T mutation. As the diagnosis of GSD1a in this family was made only after these three patients reached adulthood, dna diagnosis may help early identification of GSD1a patients and prevention of the progression of the disease. This dna-based diagnosis permits prenatal diagnosis in at-risk patients and may facilitate screening and counselling of patients clinically suspected of having this disease. ( info) |
3/162. Long-term outcome of liver transplantation in patients with glycogen storage disease type Ia. liver transplantation may be indicated in patients with GSD type Ia when dietary treatment fails or when hepatic adenomas develop, because they carry a risk of liver cancer or severe intratumoral haemorrhage. Published reports on the results of liver transplantation in patients with GSD Ia include 10 patients and provide little information on long-term outcome. In particular, it is not known whether liver transplantation prevents renal failure due to focal segmental glomerulosclerosis. We report here on 3 patients with GSD Ia in whom liver transplantation was performed at 15, 17 and 23 years of age because of multiple hepatic adenomas in all 3 patients with a fear of malignant transformation, and of poor metabolic balance and severe growth retardation in the youngest one. Renal function was normal in all patients. During the 6-8 years following transplantation, the quality of life has initially greatly improved, with none of the previous dietary restraints and a spectacular increase in height. However, long-term complications included chronic hepatitis c in one patient, gouty attacks in another and focal segmental glomerulosclerosis with progressive renal insufficiency in the third. These results: (1) confirm that liver transplantation restores a normal metabolic balance in patients with GSD Ia, allows catch-up growth and improves the quality of life; (2) suggest that liver transplantation may be considered in teenagers with unresectable multiple adenomas because of a lack of clear-cut criteria to detect malignant transformation early; and (3) suggest that liver transplantation does not prevent focal segmental glomerulosclerosis associated with GSD Ia. ( info) |
4/162. Glycogen storage disease type Ib: structural and mutational analysis of the microsomal glucose-6-phosphate transporter gene. Glycogen storage disease type Ib is caused by a mutation in the gene encoding microsomal glucose-6-phosphate (G6P) transporter. We determined the exon/intron organization of the G6P transporter gene. Four overlapping genomic fragments containing the entire coding region of the gene were amplified by polymerase chain reaction (PCR) using exonic primers, and their nucleotide sequences were determined. The gene spans 4.5 kb and has eight exons. All exon/intron boundaries adhered to the canonical AG/GT rule. We then designed eight pairs of PCR primers to amplify all coding exons for a mutational analysis and studied five Japanese patients with the disease. Two novel homozygous mutations were identified in two families: a three-base deletion (delV235) in exon 2 in a consanguineous family and a splicing mutation (IVS7 1G-->T) in intron 7 in a nonconsanguineous family. Patient 3 was a compound heterozygote of W118R and IVS1 1G-->A, both of which we previously identified [Kure et al., 1998: Biochem Biophys Res Commun 248:426-431]. patients 4 and 5 were homozygotes of W118R. Including our previous study, we found a total of ten W118R alleles in nine Japanese patients. The results support our previous suggestion that W118R is prevalent among Japanese patients. The genomic sequence data and mutation spectrum obtained from the Japanese patients will facilitate genetic diagnosis of glycogen storage disease type Ib. ( info) |
5/162. Nutritional deficiencies in a patient with glycogen storage disease type Ib. The current mainstay of treatment in glycogen storage disease type i (GSD I) is dietary management that includes providing a frequent source of glucose to prevent hypoglycaemia. To ensure compliance, routine follow-up by a health care team, including a dietitian, experienced in the treatment of GSD is necessary. We describe an adolescent patient with GSD Ib in good metabolic control who was admitted with a 3-month history of weakness, depression, vomiting, decreased appetite and a 11.4-kg weight loss. He had a recent onset of unsteady gait, inability to write, and sore mouth. After an extensive work-up, the patient was found to have vitamin B12, folate, iron and other nutritional deficiencies, which explained his symptoms. The patient improved within 72 h of initiation of total parenteral nutrition and therapeutic doses of deficient micronutrients, with a complete recovery in 2 months. Dietary restrictions, dependence on non-food products (e.g. cornstarch in GSD I), and social and developmental issues place individuals with metabolic disorders at a high risk for developing an array of nutritional deficiencies. This case highlights the importance of both close follow-up of the metabolic control and close monitoring of growth and nutritional intake in individuals with inborn errors of metabolism. This case also illustrates the importance of daily supplementation with appropriate multivitamins, calcium and other minerals needed to meet the Recommended Dietary Allowances (RDAs) in these patients. ( info) |
6/162. pregnancy and von Gierke's disease. A detailed description of the course of pregnancy in a patient with von Gierke's disease is presented. Careful dietary control together with proper management of the hematologic complications of the disease led to a successful outcome. ( info) |
7/162. Heterogenous glycogen storage disease in one family. Three brothers, aged 17, 14 and 4 ye presented. Deficiency of glucose-6-phosphatase was associated with deficiency of acid maltase in one and debranching enzyme in the other. Enzyme analyses could not be performed in the youngest sibling. ( info) |
8/162. Type Ib glycogenosis. Type Ib glycogenosis is a rare glycogen storage disorder resulting from a defect in the enzyme, glucose-6-phosphatase microsomal translocase. We report a case of Type Ib glycogenosis in an 18 month-old male child who presented with a history of hypoglycemic seizures and recurrent infections and had a massive hepatomegaly, recurrent hypoglycemia, hyperuricemia, hypertriglyceridemia, neutropenia and fasting lactacidemia which decreased sharply on glucose administration. ( info) |
9/162. Long-term follow-up of portacaval shunt in glycogen storage disease type 1B. In two girls with glycogen storage disease (GSD) type 1b, terminolateral portacaval shunt (PCS) with partial circular resection of the lobus quadratus of the liver was performed at the age of 12 and 10 years, respectively. At that time, the patients had a height of -3.1 and -1.7 SDS, respectively. PCS resulted in a spectacular growth spurt of 35 cm within the first 5 years after surgery in both of them. As first sign of puberty, breast enlargement started 2.5 years after PCS in both patients. Improved glucose tolerance was evidenced by increased levels of blood glucose and insulin after PCS. diet with raw cornstarch (CS), 2g/kg body weight four times daily, was started 8 years after PCS in patient 1, but initiated with nightly gastric feeding at the age of 2 years in patient 2, 8 years before PCS. Treatment with recombinant granulocyte colony-stimulating factor (rhGCSF), 6 microg/kg body weight every 36-48 h, was started 20 years after PCS in patient 1, but only 1 month before PCS in patient 2. Progressive development of up to 7-8 liver adenomas was observed after PCS, but without conclusive signs of malignancy on Ferrit MRI. The PCS is still open 23 and 7 years after PCS, respectively. Terminolateral PCS with partial circular resection of the lobus quadratus of the liver associated with dietary control and rhGCSF might still have a place in the treatment of GSD type 1b because it improves the tolerance to fasting and the quality of life and moreover yields excellent metabolic control. CONCLUSION: Treatment of glycogen storage disease type 1b by portacaval shunt might be considered in patients with height-for-age below the 3rd percentile occurring in spite of dietary control, or before considering liver transplantation which, if necessary, can still be performed after shunt surgery. ( info) |
10/162. Heterogeneous mutations in the glucose-6-phosphatase gene in Japanese patients with glycogen storage disease type Ia. Glycogen storage disease type Ia (GSD-Ia) is an autosomal recessive disorder of glycogen metabolism caused by glucose-6-phosphatase (G6Pase) deficiency. It is characterized by short stature, hepatomegaly, hypoglycemia, hyperuricemia, and lactic acidemia. Various mutations have been reported in the G6Pase gene (G6PC). However, in Japanese patients, a g727t substitution was found to be the major cause of GSD-Ia, accounting for 20 of 22 mutant alleles [Kajihara et al., 1995], and no other mutations have been found in this population. We analyzed four Japanese GSD-Ia patients and identified three other mutations in addition to the g727t. They included two missense mutations (R83H and P257L) and one nonsense mutation (R170X). Each of the three mutations exhibited markedly decreased G6Pase activity when expressed in COS7 cells. A patient homozygous for R170X showed multiple episodes of profound hypoglycemia associated with convulsions, while P257L was associated with a mild clinical phenotype. The presence of R170X in three unrelated families may implicate that it is another important mutation in the etiology of GSD-Ia in Japanese patients. Thus, the detection of non-g727t mutations is also important in establishing the dna-based diagnosis of GSD-Ia in this population. ( info) |