Novel fructose-1,6-bisphosphatase gene mutation in two siblings.

Fructose-1,6-bisphosphatase (FBPase) deficiency is an autosomal, recessively inherited disease that progresses with severe hypoglycemia, and metabolic attacks result in a defect in gluconeogenesis. If not appropriately treated, and if fructose is not excluded from the diet, the outcome could be fatal. Two Turkish children with FBPase deficiency were diagnosed based on mutation of the FBP1 gene. The first, a 2-year-old girl, was referred to our clinic because of lactic acidosis, uncorrectable hypoglycemia, and increased transaminases. FBPase deficiency was suspected in the patient, who recovered dramatically after a high-dose glucose infusion and adequate bicarbonate replacement. The second patient, a five-and-a-half-year-old male sibling of the patient, was also hospitalized, twice, because of hypoglycemic attacks and metabolic acidosis. Different from previous analyses, a homozygous c.658delT mutation was detected at exon 5 of the FBP1 gene in the two siblings. As a result of this mutation, there was a TGA (stop codon) at exon 6. There was first-degree consanguinity between the parents. These two cases were the first FBP1 gene mutations reported in our country.

Fructose-1,6-diphosphatase deficiency: a rare cause of prolonged prothrombin time.

A 20-year-old woman presented with severe life-threatening metabolic acidosis and hypoglycemia. In addition, her blood tests revealed elevated hepatic enzymes and a prolonged prothrombin time, with a reduction in factor VII activity. After treatment with a glucose and bicarbonate-containing intravenous infusion, there was a dramatic clinical improvement and normalization of the prothrombin time within 2 days. The patient was found to have fructose-1,6-diphosphatase deficiency, a rare metabolic disorder which has not been described previously as causing coagulation defects.