Enzyme Replacement Therapy in a Patient with Gaucher Disease Type III: A Paradigmatic Case Showing Severe Adverse Reactions Started a Long Time After the Beginning of Treatment.

INTRODUCTION: There are three recombinant enzymes available for the treatment of Gaucher disease (GD): imiglucerase, velaglucerase alfa, and taliglucerase alfa. CASE REPORT: A male GD type III patient, 14 years old, genotype p.L444P/L444, diagnosed at 2 years old. He had been treated with imiglucerase for 9 years since the diagnosis. In 2008, however, he presented a severe adverse reaction to imiglucerase, characterized by cough, laryngeal stridor, and periorbital edema. The infusions were suspended for 3 months when imiglucerase was restarted with premedication and a slower infusion rate. After 5 months, he presented a new adverse reaction with vomiting, tachypnea, cough, and periorbital edema. Intradermal testing confirmed IgE-mediated reaction but serological tests were negative. After 2 years and 10 months with no specific treatment and a significant worsening of the clinical picture, taliglucerase alfa was prescribed, with premedication and a slower infusion rate. At the first infusion, he presented moderate adverse reaction and the infusions were suspended. After 2 months, velaglucerase alfa was initiated uneventfully. He maintains day-hospital infusions without premedication and shows improvement of clinical and laboratory parameters. CONCLUSION: This is the first report of the use of velaglucerase alfa in patients with GD type III. The use of recombinant enzymes is safe for the majority of GD patients, but severe reactions may occur even many years after the beginning of the treatment. Premedication and slower infusion rate reduce the incidence of adverse reactions but may not solve the problem. This case report further demonstrates the different safety profile among all the recombinant enzymes available for the treatment of GD.

KIR genes and HLA class I ligands in Gaucher disease.

UNLABELLED: Gaucher disease (GD) is caused by reduced activity of the lysosomal enzyme glucocerebrosidase, which leads to a buildup of glucocerebroside within the cells and chronic stimulation of the immune system. GD is associated with clinical variability even in the same family, which suggests the influence of modifier genes. Natural killer (NK) cells play an important role in the immune response, and their number is decreased in GD. Killer-cell immunoglobulin-like receptors (KIR) regulate the activity of NK cells through an interaction with specific human leukocyte antigen (HLA) class I molecules on target cells. OBJECTIVES: To analyze the variability of KIR genes in a sample of GD patients from Southern Brazil, and look for associations between variants and clinical manifestations. METHODOLOGY: Thirty-one GD patients (24 mild, 4 moderate, and 3 severe) were included in the study. Fifteen KIR genes, HLA-C and HLA-Bw4 were analyzed using SSP-PCR. Clinical, biochemical, and radiological data were collected by means of a chart review. RESULTS/DISCUSSION: Age at symptom onset was associated with KIR2DL2 and KIR2DS2 in combination with the ligand HLA-C1 (p=0.038). Patients who have the HLA-C2 variant appear to have more mono- and polyclonal bands on protein electrophoresis (p=0.007, OR 21.3). There was no between-group significant difference in the frequencies of KIR/HLA variants. CONCLUSION: Although exploratory our data suggest a possible association of KIR/HLA variants and the severity of GD. Further study of KIR/HLA variants is required, as they seem to be a phenotype-modifying factor in this disease.

Human leukocyte antigens and Gaucher disease.

BACKGROUND: Gaucher disease (GD) is caused by the reduced activity of lysosomal enzyme glucocerebrosidase, which leads to the accumulation of glucocerebroside in macrophages and a chronic stimulation of the immune system. GD is divided into 3 main types according to the presence or absence of neurological involvement and to its presentation (acute or chronic). Gaucher cells show an increase in their expression of HLA-DR antigens on their surface, and there is an increase in levels of antigen-presenting molecules. Over 100 diseases have already been associated to HLA antigens; however, this association has never been studied in GD. OBJECTIVES: To analyze the variability of HLA genes in a Southern Brazilian sample of GD patients, to compare it with controls, and to look for associations with clinical manifestations. METHODOLOGY: Thirty-one GD patients (24 mild, 4 moderate, and 3 severe) were included in the study. They were typed for HLA A, B, and DR and compared to 250 healthy controls. The clinical data were obtained from the review of medical records. RESULTS/DISCUSSION: There was a significant difference in the frequency of B37 allele among patients when compared to controls (p=0.011, OR 13.28). An association was found between DR11 (p=0.008) and DR13 (p=0.011) alleles and the severity of the disease. DR11 allele seems to be associated to neurologic compromise, while DR13 seems to be associated to osteonecrosis. CONCLUSION: Our data suggest a possible association of HLA variants and GD. The HLA variants must be further studied, for they seem to be a phenotype-modifier factor for GD.