Granulocyte colony-stimulating factor in glycogen storage disease type 1b. Results of the European Study on Glycogen Storage Disease Type 1

Patients with glycogen storage disease type 1b (GSD-1b) have neutropenia and neutrophil dysfunction that predispose to frequent infections and inflammatory bowel disease (IBD), for which granulocyte colony-stimulating factor (GCSF) is given. To investigate the use and the value of GCSF treatment in GSD-1b, a retrospective registry of GSD-1 patients born between 1960 and 1995 in 12 European countries was established. Included were 57 GSD-1b patients. Unglycosylated GCSF was given to 18 patients, median age of starting therapy was 8 years, longest duration of therapy 7 years. Dose varied between 2-10 mug/kg, with a frequency from daily to twice per week. Neutropenia (defined as an absolute neutrophil count <0.5x10(9)/l) was found in 49 patients. In untreated patients, a significant decrease of haemoglobin, platelet counts and leucocyte counts with increasing age (P<0.032, P<0.04 and P<0.001 respectively) was noted, whereas neutrophil counts remained low but stable with increasing age. In nine patients who were treated longer than 1 year, median neutrophil counts increased significantly and simultaneously median leucocyte counts and platelet counts decreased significantly. In all patients treated, the number and severity of infections decreased and the severity of IBD improved subjectively. The most serious complication of GCSF treatment was marked splenomegaly (four patients). Conclusion: in this retrospective study a significant haematological effect was documented and a subjective improvement of infections and inflammatory bowel disease. In view of the uncertainty, prospective controlled trials seem warranted to clarify the indication for the use of granulocyte colony-stimulating factor in this disease.