Diagnosis and treatment of Gaucher disease

Gaucher disease (Morbus Gaucher) is the most common lysosomal storage disorder. Incidence of the disease is around 1:40-60 000 individuals and it is assumed that in Croatia we have 20-30 patients with Morbus Gaucher. The cause of this storage disorder is an autosomal recessive inherited glucocerebrosidase deficiency, which, depending upon the residual activity of the enzyme, results in a more or less decreased breakdown of the sphingolipids. The disease is extremely serious, disabling and can be mortal in the near or distant future without treatment. Morbus Gaucher is recognized in three types. Type I or what is known as the non-neuronopathic form is most common in Europe while the neuronopathic forms (type II and III) are much more rare (5-10%). Types II and III are characterized by central nervous system involvement and are usually diagnosed in childhood. Disease manifestations are observed in various human organs. The most common disease features involve the liver, spleen, bones, lungs and brain. Morbus Gaucher is a lysosomal storage disorder and disease manifestation can be observed in almost all human organs. Diagnosis of Morbus Gaucher is easily established by measuring enzyme glucocerebrosidase activity in leukocytes or fibroblasts. Disease activity can be predicted by measuring the chitotriosidase level in sera. Enzyme replacement therapy with imiglucerase (Cerezyme ®) is now the therapeutic gold standard. Imiglucerase prevents progressive manifestation of the disease and patients have a normal life. The cost of the treatment is high due to the cost of the recombinant technology, which is used to produce imiglucerase. The cost of the enzyme replacement therapy is 150-200,000 EUR per year for imiglucerase in a typical adult patient. Due to the high cost of patient treatment the Ministry of Health of Republic of Croatia, and the Croatian Health Insurance Company established a special program in 2002 for what they called „Expensive drug treatment“. This program covers treatment costs for patients with inherited metabolic disorders, adenosine deaminase deficiency, chronic myeloid leukemia, AIDS, multiple sclerosis, juvenile arthritis and ovarian cancer. So far 11 adult patients with Gaucher disease have been diagnosed in Croatia, a 7 of them are on enzyme replacement therapy with imiglucerase. According to our experience administration of imiglucerase has decreased spleen and liver size and the number of bone pain crises, as well as normalization of platelet and red blood cells. Administration of the imiglucerase does no reverse bone changes e.g. avascular hip necrosis or vertebra collapses, but prevents further bone deterioration. Accordingly, treatment with imiglucerase should be started immediately after establishing diagnosis to prevent irreversible changes to human organs.