ABSTRACT: We report on a case of a little girl patient diagnosed with Gaucher disease (GD) type 1 in her early childhood and our first experience with enzyme replacement therapy (ERT). She was first diagnosed accidentally with enlarged spleen during a pediatric examination when she was three years old, but the family ignored investigations; she was hospitalized for diagnosis at six years old. The GD was confirmed based on: clinical manifestations of left abdominal flank pain, multiple bruising, general weakness, bone pain, low appetite, failure to thrive <5th percentile, minor hepato- and severe splenomegaly, enlarged submaxillary lymph nodes, associated by anemia with normal platelets; low activity of beta-Glucosidase, two found mutations in GBA gene, Gaucher cells in bone marrow. The ERT was initiated with Imiglucerase (54 UI/kg/2 wks) two years later after diagnosis, avoiding the splenectomy. Subsequently, the platelets showed the first a promising result, gradually increasing their number every 2 weeks and maintaining it in good parameters till the reported moment (2.5 yrs from the start). The hemoglobin level was appreciated within normal ranges 3 months after ERT start and stabilized completely after 6 months. On the other hand, the red blood count normalized within 20 months of applied therapy. The Lyso-GL-1 decreased by 30% after three months of therapy, no antibodies to Imiglucerase were found. The initial spleen volume (1178.19 cm3) decreased by almost 60% in 6 months of ERT, reaching absolutely normal dimensions after 9 months. The ERT with Imiglucerase was tolerated very well by the patient, showing a clear improvement of clinical symptoms after 4-6 months of therapy, hematological picture and splenomegaly solving. Even if the little patient had to come every 2 weeks for infusion, her quality of life improved a lot, being a totally happy child, going to school and having friends. The ERT should be initiated immediately after diagnosis to prevent the multisystem complications.