Gaucher disease and bone: laboratory and skeletal mineral density variations during a long period of enzyme replacement therapy.

The usefulness of bone turnover markers in Gaucher disease is still unclear and their utility in monitoring the effects of enzyme replacement therapy (ERT) on bone metabolism has not yet been investigated exhaustively. Skeletal involvement seems to improve slowly during ERT, but only a few studies evaluating bone mineral density (BMD) changes during a long follow-up period have been reported. The aim of this study was to assess the efficacy of ERT on bone involvement in a group of 12 type I Gaucher disease (GD I) patients by monitoring biochemical indices of bone resorption/formation and BMD measured by dual energy x-ray absorptiometry (DEXA). Serum (calcium, phosphorus, bone alkaline phosphatase isoenzyme, carboxyterminal propeptide of type I procollagen (PICP), carboxyterminal telopeptide of type I collagen (ICTP), osteocalcin, intact parathyroid hormone) and urinary (calcium, phosphorus, hydroxyproline and free deoxypyridinoline) markers of bone metabolism and lumbar BMD were measured at baseline, after 6 and 12 months, and then every year for a mean ERT follow-up period of 4.5 years (range 4.4-6 years). Twelve healthy adult subjects matched for age and sex were tested as negative controls. A significant decrease of PICP was detected in the patient group at baseline (mean value 100.52 ng/ml vs 142.45 ng/ml, p = 0.017), while ICTP was remarkably higher: mean value 3.93 ng/ml vs 2.72 ng/ml, p = 0.004 (two-sided Student's t-test). No changes in bone formation indices were observed during the follow-up period, while urinary calcium excretion increased significantly from 0.065 to 0.191 mg/mg creatinine (p = 0.0014) (repeated measures ANOVA). A significant BMD improvement was also detected after an average ERT period of 4.5 years: Z-score increased from -0.81 to -0.56 (p = 0.005) (two-sided Student's t-test). These data evidenced the ineffectiveness of the biochemical markers used in monitoring ERT efficacy in GD I skeletal involvement, whereas DEXA was demonstrated to be a reliable method with which to follow up BMD improvement.

Aminohydroxypropylidene-biphosphonate in the treatment of bone lesions in a case of Gaucher's disease type 3.

Gaucher disease is the most prevalent lysosomal storage disorder. It is characterized by an autosomal recessive inheritance of a deficiency of lysosomal acid glucocerebrosidase. Three clinical phenotypes are recognized: type 1 (non-neuronopathic), type 2 (acute neuronopathic), type 3 (subacute neuronopathic). Bone lesions are associated with type 1 and type 3 Gaucher disease. Skeletal involvement is secondary to the progressive accumulation of histiocytes and macrophages laden with glucosylceramide in bone marrow. Our patient was a female type 3 Gaucher patient who was referred to us at the age of 3 years with a neurological symptomatology and severe bone lesions (bilateral fracture of the femur heads, lytic process of the bone matrix of the femurs and distal flask deformity, kyphoskoliosis and chest deformity). The baby was constrained to a wheel-chair. The use of (3-amino-1-hydroxypropylidene)-1,1-biphosphonate (APD) was described in a case of Gaucher disease with very severe bone lesions. We used periodic iv infusions of APD (10 mg every 3 weeks) in our patient for a period of 20 months; after that, enzyme replacement therapy (alglucerase) was commenced. APD treatment showed normalization of bone density, formation of bone callus at the femural heads, positive calcium balance. The urinary Ca/Cr ratio and TRP were consistently normal during therapy. After 9 months of alglucerase therapy the patient was able to walk again. The data indicate that APD therapy can find an indication in Gaucher patients with severe bone involvement.

Immunological patterns in monoarticular juvenile rheumatoid arthritis.

Seven pediatric patients with monoarticular arthritis, three of whom had a recent onset form and the remaining four a disease of longer duration, were examined for possible modifications of their immunological parameters. The diagnosis of JRA was made on all these patients according to the ARA criteria after a follow-up of at least two years. Humoral and cellular abnormalities of the immune system were searched for in peripheral blood, synovial fluid and synovial membrane. No evidence for complement consumption and for increased levels of immune-complexes was found in the sera and in the synovial fluids of these patients, who were all seronegative. Some patients had antinuclear antibodies in their sera and synovial fluids. With regard to the lymphocyte distribution, whereas only some patients had an increased number of circulating B cells, the majority had a decreased CD4+/CD8+ ratio in the synovial fluid compared to the ratio found in the peripheral blood. A massive infiltration of CD4+ cells and macrophages and the presence of a substantial number of OKT9+ cells was found in the synovial membranes.