Enhancing access to treatment for Gaucher disease in India: The need for indigenous manufacturing

Gaucher disease (GD) is a prevalent lysosomal storage disorder (LSD) that significantly impacts individuals' lives. However, the exorbitant prices of GD medications pose a major hurdle in ensuring widespread availability and affordability of treatment in India. The country heavily relies on imported medications, leading to high costs and limited access for many patients. This article aims to address this issue by advocating for the establishment of indigenous manufacturing capabilities for GD medicines in India. Through an examination of the current landscape of GD treatment, including the availability, affordability, and challenges associated with imported medications, this article highlights the urgent need for localized production. By focusing on the potential benefits of indigenous manufacturing, such as reduced costs, increased accessibility, and enhanced availability, this research aims to provide insights and recommendations to policymakers, healthcare professionals, and relevant stakeholders. The findings underscore the importance of developing domestic manufacturing capabilities to address the affordability and accessibility challenges faced by GD patients in India. The research also emphasizes the potential positive impact on the healthcare system, the pharmaceutical industry, and the overall well-being of individuals with GD. Ultimately, this article seeks to stimulate discussions and actions towards creating a sustainable framework for indigenous manufacturing of GD medicines, thereby improving the lives of those affected by this rare and debilitating condition.

Gaucher disease prevalence in 600 patients affected by monoclonal gammopathy of undetermined significance

BACKGROUND

Gaucher disease (GD) is a rare autosomal recessive inherited disorder caused by the lysosomal enzyme acid β-glucosidase deficiency. Many patients experience a critical delay in the diagnosis of up to 8-10 years due to its rarity and variability in signs and symptoms, with the consultation of several specialists.

PATIENTS AND METHODS

This prospective observational study analyzed the prevalence of GD in 600 patients with monoclonal gammopathy of uncertain significance (MGUS) from January 2018 until February 2022.

RESULTS

The mean age of participants was 66 years, with a mean monoclonal component of 0.58 g/dL. In 433 MGUS patients with available data, anemia (hemoglobin level < 10 g/dL) was present in 31 patients (7%), and thrombocytopenia (platelet count <100.000/mm3 ) in 24 (5.5%). Of 600 MGUS patients tested for acid β-glucosidase enzyme activity, 7 patients (1.2%) had activity below 2.5 nmol/h/mL. In comparison, GBA gene analysis was executed in 110 patients. It revealed 4 patients (0.7%) affected by GD (3 patients with compound heterozygous mutation and 1 with homozygous mutation), with a prevalence of 1 every 150 MGUS patients. Furthermore, 12 out of the remaining 106 evaluated patients (11%) were carriers of a single heterozygous mutation while having regular enzyme activity.

CONCLUSIONS

The clinical heterogeneity of GD and frequent lack of awareness among physicians often lead to diagnostic delays and severe clinical manifestations. The role of MGUS in the presence of at least one clinical sign, such as low platelet count, organomegaly, bone pain, or bleeding tendency, could aid in initiating GD screening with DBS, thus reducing the period between symptom onset and the diagnosis of this rare disease.

A rare disease in adult women: Gaucher disease

Gaucher disease is a rare, autosomal recessive disorder caused by inborn errors of metabolism. Globally, more than 27 million people are born each year, and approximately 19,000 neonates are born with lysosomal storage disease. We report a rare case of Gaucher disease in an adult female patient of non-consanguineous parents in a subtropical area of Jiangxi Province, China. This area has a high prevalence of schistosomiasis. The diagnosis of this case posed a great challenge because of the possible differential diagnoses of pancytopenia with hepatomegaly and giant splenomegaly. The key component of the patient's diagnosis was her medical history in which it was documented that her brother had died of hepatocellular carcinoma of unknown origin. We diagnosed the patient through a combination of a pathological biopsy and imaging plus the patient's medical history.

Development of a rare disease algorithm to identify persons at risk of Gaucher disease using electronic health records in the United States

BACKGROUND

Early diagnosis of Gaucher disease (GD) allows for disease-specific treatment before significant symptoms arise, preventing/delaying onset of complications. Yet, many endure years-long diagnostic odysseys. We report the development of a machine learning algorithm to identify patients with GD from electronic health records.

METHODS

We utilized Optum's de-identified Integrated Claims-Clinical dataset (2007-2019) for feature engineering and algorithm training/testing, based on clinical characteristics of GD. Two algorithms were selected: one based on age of feature occurrence (age-based), and one based on occurrence of features (prevalence-based). Performance was compared with an adaptation of the available clinical diagnostic algorithm for identifying patients with diagnosed GD. Undiagnosed patients highly-ranked by the algorithms were compared with diagnosed GD patients.

RESULTS

Splenomegaly was the most important predictor for diagnosed GD with both algorithms, followed by geographical location (northeast USA), thrombocytopenia, osteonecrosis, bone density disorders, and bone pain. Overall, 1204 and 2862 patients, respectively, would need to be assessed with the age- and prevalence-based algorithms, compared with 20,743 with the clinical diagnostic algorithm, to identify 28 patients with diagnosed GD in the integrated dataset. Undiagnosed patients highly-ranked by the algorithms had similar clinical manifestations as diagnosed GD patients.

CONCLUSIONS

The age-based algorithm identified younger patients, while the prevalence-based identified patients with advanced clinical manifestations. Their combined use better captures GD heterogeneity. The two algorithms were about 10-20-fold more efficient at identifying GD patients than the clinical diagnostic algorithm. Application of these algorithms could shorten diagnostic delay by identifying undiagnosed GD patients.

Incidence of Pulmonary and Respiratory Conditions in Gaucher Disease from 2000 to 2020: A Multi-institutional Cohort Study

BACKGROUND/AIM

Gaucher disease (GD) is a rare lysosomal storage disorder that can involve the lungs and pulmonary vasculature. The long-term effects of GD on respiratory health remain unclear due to limited data on the natural history of this disease. We analyzed electronic health records for 11,004 patients with GD over 10-20 years to determine the incidence of pulmonary hypertension (PH), lung disease, and other respiratory comorbidities and better understand disease course to guide management.

PATIENTS AND METHODS

We conducted a retrospective cohort study using the TriNetX research database of 130 million international patients. The incidence of primary/secondary PH, pulmonary heart disease, interstitial/obstructive/restrictive lung disease, pulmonary hemorrhage, and pulmonary embolism was assessed in patients with GD from 2000-2020.

RESULTS

Incidence rates of all conditions assessed increased from 10 to 20 years of follow-up. Excess risk of PH, lung disease, and pulmonary hemorrhage was significantly higher in GD patients after 20 versus 10 years.

CONCLUSION

Extended follow-up in GD is associated with substantially higher risks of PH, lung disease and other respiratory comorbidities, highlighting the need for close monitoring and early intervention to mitigate long-term pulmonary decline. Improved understanding of mechanisms driving respiratory deterioration can support the development of novel treatments to optimize outcomes in this population at high risk of pulmonary morbidity and mortality.

Cancer risk and gammopathies in 2123 adults with Gaucher disease type 1 in the International Gaucher Group Gaucher Registry

There are numerous reports of cancers in Gaucher disease (GD) from mostly small single-center studies; however, precise risk estimates and cancer types involved have not been delineated. We conducted a study involving 2123 patients with GD type 1 (GD1) to assess the incidence of hematological malignancies, gammopathies, and solid tumors in an international observational study, the International Cooperative Gaucher Group Gaucher Registry (Clinicaltrials.gov: NCT00358943). Risk for cancer overall and for each type of malignancy was compared to the United States (US) population using the Surveillance, Epidemiology, and End Results database. Natural history of gammopathy was determined through assessing the progression from a diagnosis of monoclonal gammopathy of unknown significance (MGUS) to multiple myeloma (MM). Risk for hematological malignancies was more than four times higher than expected compared to the general population: non-Hodgkin lymphoma was approximately three times higher; MM was approximately nine times higher. Age-specific incidence rates of MGUS were unexpectedly high among younger patients. The 10-year cumulative incidence of MM after diagnosis of MGUS was 7.9%, comparable to the general population. Compared to the general US population, GD1 patients were at higher risk for solid malignancies of liver (2.9 times), kidney (2.8 times), melanoma (2.5 times), and breast (1.4 times). Colorectal, prostate, and lung cancer risks were lower than expected. These findings help advance care of patients with GD1 by supporting recommendations for individualized monitoring for malignancies and antecedents such as MGUS for MM and provoke important questions of the role of glucosylceramide and related sphingolipids in cancer biology.

Evaluation of the Nutritional Status of Gaucher Disease Type I Patients under Enzyme Replacement Treatment

(1) Background: Gaucher disease (GD) is a rare lysosomal storage disease. The few studies analyzing Resting Energy Expenditure (REE) in GD involved mainly untreated patients and supported a hypermetabolic condition possibly due to the associated inflammatory state. Definitive conclusions could not be drawn also because of the heterogeneity and the small size of the samples investigated. In order to expand current knowledge concerning, in particular the condition of patients under Enzyme Replacement Therapy (ERT), we evaluated the nutritional status of a relatively large sample of GD patients followed at Federico II University Hospital in Naples, Italy. (2) Methods: The study, having a cross-sectional design and involving 26 patients on ERT, included routine biochemical analyses, bioelectrical impedance analysis, indirect calorimetry, and administration of food frequency and physical activity questionnaires. The results in GD patients were compared with those from an appropriate control group. (3) Results: GD patients had normal biochemical parameters in 80% of cases, except for HDL-cholesterol, consumed a hyper-lipidic diet, and had a 60% prevalence of overweight/obesity. Body composition did not differ between patients and controls; however, measured REE was significantly lower than predicted and was reduced in comparison with the healthy controls. (4) Conclusions: This study provided novel elements to the present knowledge about REE and the nutritional status of GD patients under ERT. Its results warrant confirmation in even larger GD population samples and a more in-depth investigation of the long-term effects of treatment superimposed on the basic pathophysiological disease condition.

Screening for Gaucher Disease Using Dried Blood Spot Tests: A Japanese Multicenter, Cross-sectional Survey

Objective For patients with Gaucher disease (GD), a rare, inherited lysosomal storage disease, obtaining a definitive diagnosis is currently time-consuming and costly. A simplified screening method to measure the glucocerebrosidase (GBA) activity using dried blood spots (DBS) on filter paper has recently been developed. Using this newly developed screening method, we evaluated real-world GD screening in patients suspected of having GD. Methods This multicenter, cross-sectional, observational study with a diagnostic intervention component evaluated real-world screening in patients suspected of having GD based on their clinical symptoms and a platelet count <120,000/μL. The endpoint was the number of patients with low GBA activity determined using DBS. Results In 994 patients who underwent initial DBS screening, 77 had low GBA activity. The assay was not repeated in 1 patient who was diagnosed as having a high possibility of GD due to clinical symptoms, and a further 21 patients completed the study without undergoing the second assay. Of the remaining 55 patients who had 2 DBS assays performed, 11 had a low GBA activity in both assays. Overall, DBS screening identified 12 (1.2%) patients with a low GBA activity, a proportion consistent with prior screening studies. Conclusion These results suggest that the simplified DBS method was less burdensome to patients, was easily utilized by many physicians, and could be a useful first-tier screening assay for GD prior to initiating burdensome genetic testing.

Gaucher disease type 1 patients from the ICGG Gaucher Registry sustain initial clinical improvements during twenty years of imiglucerase treatment

BACKGROUND

Alglucerase enzyme replacement therapy was approved for Gaucher disease (GD) in the United States in 1991; imiglucerase in 1994. We report hematologic, visceral, bone pain, bone crisis, height, weight, and Body Mass Index (BMI) outcomes in patients treated for 20 (±3) years with subset analyses based on pre-treatment severity, genotype, and age at treatment initiation.

METHODS

GD type 1 (GD1) patients in the ICGG Gaucher Registry with complete sets of baseline, 10-year, and 20-year data are included (N = 475). Ten-year and 20-year data are compared to pre-treatment baseline, stratified by splenectomy status.

RESULTS

Non-splenectomized patients: Improvements observed at 10 years were maintained at 20 years for most outcomes. Mean changes from baseline at 10 and 20 years, respectively, were: spleen volume: 18.2 multiples of normal (MN) to 5.1 MN and 4.2 MN; liver volume: 1.8 MN to 1.0 MN and 1.0 MN; hemoglobin: 11.4 g/dL to 13.7 g/dL and 13.8 g/dL; platelet count: 91.6 × 10⁹/L to 168.0 × 10⁹/L and 169.1 × 10⁹/L; without bone crisis: 85.0% to 98.2% and 96.5%; without bone pain: 52.5% to 72.0% at 10 years, no significant change at 20 years (58.5%). Splenectomized patients: significant changes were observed in liver volume: 2.3 MN to 1.1 MN and 1.0 MN; hemoglobin: 11.7 g/dL to 13.3 g/dL and 13.4 g/dL; platelet count: 229.1 × 10⁹/L to 288.1 × 10⁹/L and 257.0 × 10⁹/L; without bone crisis: 52.2% to 91.3% and 100%; without bone pain: 16.3% to 30.6% (not significant) and 46.9%. Similar results were found in each of the subset analyses. Patients who start treatment during childhood have normal weight and height in young adulthood. Many treated adult patients are overweight or obese; however, this is consistent with BMI trends observed in the general population. After 1-2 years, the average biweekly imiglucerase dose is ~40 units/kg body weight.

CONCLUSION

Imiglucerase is an effective, long-term treatment for GD1. In a long-term observational setting, improvements seen during early treatment years are sustained by continuing treatment for 20 years, except for bone pain in non-splenectomized patients. These results are consistent when analyzed by different patient subsets, including by disease severity.

Gaucher disease and SARS-CoV-2 infection: Experience from 181 patients in New York

SARS-CoV-2 infection carries high morbidity and mortality in individuals with chronic disorders. Its impact in rare disease populations such as Gaucher disease (GD) is unknown. In GD, decreased acid β-glucosidase activity leads to the accumulation of inflammatory glycosphingolipids and chronic myeloid cell immune activation which a priori could predispose to the most severe effects of SARS-CoV-2. To evaluate the determinants of SARS-CoV-2 infection in GD, we conducted a cross-sectional study in a large cohort. 181 patients were enrolled, including 150 adults and 31 children, with a majority of patients on treatment (78%). Information on COVID-19 exposure, symptoms, and SARS-CoV-2 nucleic acid and/or antibody testing was obtained during the peak of the pandemic in the New York City metropolitan area. Forty-five adults reported a primary exposure to someone with COVID-19 and 17 (38%) of these patients reported at least one COVID-19 symptom. A subset of adults was tested (n = 88) and in this group 18% (16/88) were positive. Patients testing positive for SARS-CoV-2 had significantly more symptoms (4.4 vs 0.3, p < 0.001) than patients testing negative. Among patients who were antibody-positive, quantitative titers indicated moderate to high antibody response. In GD adults, male gender, older age, increased BMI, comorbidities, GBA genotype, prior splenectomy and treatment status were not associated with the probability of reporting symptoms or testing positive. No patient required COVID-19-specific treatments and there were no deaths. Our data suggests that GD does not confer a heightened risk for severe effects of SARS-CoV-2 infection feared based on the known chronic inflammatory state in these patients.

A patient with Gaucher disease and plasma cell dyscrasia: bidirectional impact

Patients with Gaucher disease (GD), a rare autosomal recessive glycosphingolipid storage disease, commonly present to hematologists with unexplained splenomegaly, thrombocytopenia, anemia, and bone symptoms. Patients with GD may develop other manifestations, such as autoimmune thrombocytopenia, monoclonal gammopathy, multiple myeloma, or, even more rarely, other hematological malignancies; sometimes they are first diagnosed during an assessment of those disorders. Although the diagnosis and management of patients with GD have significantly evolved over the last 30 years, some patients remain poor responders to GD-specific therapy, needing novel and investigational therapies. Ideally, patients with GD, like patients with other rare diseases, should be managed by a multidisciplinary team expert with the diverse clinical manifestations and potential GD-related or -unrelated comorbidities. The hematology community should be knowledgeable regarding the presentation and the variety of hematologic complications and comorbidities associated with Gaucher disease.

A Comprehensive Study of Bone Manifestations in Adult Gaucher Disease Type 1 Patients in Argentina

Gaucher disease (GD) is the most prevalent lysosomal storage disease, and bone involvement is the most disabling condition. The aim of the present study was to evaluate bone involvement in adult patients with GD, using an observational cross-sectional study. Patients were evaluated using X-rays, bone densitometry (BMD), trabecular bone score (TBS), magnetic resonance imaging (MRI), and biochemical bone markers. Thirty-two type 1GD patients were included (mean age: 40 ± 16 years). Patients had received velaglucerase for 2.7 ± 1.4 years; 19/32 had been treated previously with imiglucerase. Ninety-four percent of subjects met therapeutic goals for hematological parameters, and eight were splenectomized (SPX). Nineteen patients had irreversible bone lesions (IL), i.e., avascular necrosis, bone infarction, and/or vertebral fractures. MRI showed marrow infiltration in 71% of patients. Patients with IL had higher bone marrow burden than those without (p = 0.001). All SPX patients had IL, a higher prevalence of bone marrow edema (p = 0.02), and lower TBS (p = 0.03) than non-SPX patients. Only 18.7% of patients had abnormal BMD, with no correlation with fractures (FX). TBS values were < 1350 in 53% of patients and tended to be lower in those with FX (p = 0.06). Patients with P1NP in the lower quartile had lower TBS (p = 0.03) than those with P1NP in the higher quartiles. TBS correlated moderately but not significantly with P1NP (r = 0.32) and BMB (r = - 0.44). A high prevalence of IL was documented. Bone quality was more affected than BMD in fracture patients. Low bone formation, active bone marrow infiltration, and splenectomy might be implicated in IL.

Population-based cohort of 500 patients with Gaucher disease in Israel

OBJECTIVE

To characterise a population-based cohort of patients with Gaucher disease (GD) in Israel relative to the general population and describe sociodemographic and clinical differences by disease severity (ie, enzyme replacement therapy [ERT] use).

DESIGN

A cross-sectional study was conducted.

SETTING

Data from the Clalit Health Services electronic health record (EHR) database were used.

PARTICIPANTS

The study population included all patients in the Clalit EHR database identified as having GD as of 30 June 2014.

RESULTS

A total of 500 patients with GD were identified and assessed. The majority were ≥18 years of age (90.6%), female (54.0%), Jewish (93.6%) and 34.8% had high socioeconomic status, compared with 19.0% in the general Clalit population. Over half of patients with GD with available data (51.0%) were overweight/obese and 63.5% had a Charlson Comorbidity Index ≥1, compared with 46.6% and 30.4%, respectively, in the general Clalit population. The majority of patients with GD had a history of anaemia (69.6%) or thrombocytopaenia (62.0%), 40.4% had a history of bone events and 22.2% had a history of cancer. Overall, 41.2% had received ERT.

CONCLUSIONS

Establishing a population-based cohort of patients with GD is essential to understanding disease progression and management. In this study, we highlight the need for physicians to monitor patients with GD regardless of their ERT status.

Diagnosis features of pediatric Gaucher disease patients in the era of enzymatic therapy, a national-base study from the Spanish Registry of Gaucher Disease

BACKGROUND

The enzymatic replacement therapy (ERT) availability for Gaucher disease (GD) has changed the landscape of the disease, several countries have screening programs. These actions have promoted the early diagnosis and avoided many complications in pediatric patients. In Spain ERT has been available since 1993 and 386 patients have been included in the Spanish Registry of Gaucher Disease (SpRGD). The aim of this study is to analyze the impact of ERT on the characteristics at time of diagnosis and initial complications in pediatric Gaucher disease patients.

AIM

To analyze the impact of ERT on the characteristics at time of diagnosis and initial complications in pediatric Gaucher disease patients.

METHODS

A review of data in SpRGD from patients' diagnosed before 18 years old was performed. The cohort was split according the year of diagnosis (≤1994, cohort A; ≥1995, cohort B).

RESULTS

A total of 98 pediatric patients were included, GD1: 80, GD3: 18; mean age: 7.2 (0.17-16.5) years, 58 (59.2%) males and 40 (40.8%) females. Forty-five were diagnosed ≤ 1994 and 53 ≥ 1995. Genotype: N370S/N370S: 2 (2.0%), N370S/L444P: 27 (27.5%), N370S/other: 47 (48%), L444P/L444P: 7 (7.1%), L444P/D409H: 2 (2.0%), L444P/other: 3 (6.2%), other/other: 10 (10.2%). The mean age at diagnosis was earlier in patients diagnosed after 1995 (p < 0.001) and different between the subtypes, GD1: 8.2 (0.2-16.5) years and GD3: 2.8 (0.17-10.2) years (p < 0.001). There were more severe patients in the group diagnosed before 1994 (p = 0.045) carrying L444P (2), D409H (2), G377S (1), G195W (1) or the recombinant mutation. The patients' diagnosed ≤1994 showed worse cytopenias, higher chance of bone vascular complications at diagnosis and previous spleen removal. The patients started ERT at a median time after diagnosis of 5.2 years [cohort A] and 1.6 years [cohort B] (p < 0.001).

CONCLUSIONS

The early diagnosis of Gaucher disease in the era of ERT availability has permitted to reduce the incidence of severe and irreversible initial complication in pediatric patients, and this has permitted better development of these patients. This is the largest pediatric cohort from a national registry.

A Review of Gaucher Disease Pathophysiology, Clinical Presentation and Treatments

Gaucher disease (GD, ORPHA355) is a rare, autosomal recessive genetic disorder. It is caused by a deficiency of the lysosomal enzyme, glucocerebrosidase, which leads to an accumulation of its substrate, glucosylceramide, in macrophages. In the general population, its incidence is approximately 1/40,000 to 1/60,000 births, rising to 1/800 in Ashkenazi Jews. The main cause of the cytopenia, splenomegaly, hepatomegaly, and bone lesions associated with the disease is considered to be the infiltration of the bone marrow, spleen, and liver by Gaucher cells. Type-1 Gaucher disease, which affects the majority of patients (90% in Europe and USA, but less in other regions), is characterized by effects on the viscera, whereas types 2 and 3 are also associated with neurological impairment, either severe in type 2 or variable in type 3. A diagnosis of GD can be confirmed by demonstrating the deficiency of acid glucocerebrosidase activity in leukocytes. Mutations in the GBA1 gene should be identified as they may be of prognostic value in some cases. Patients with type-1 GD-but also carriers of GBA1 mutation-have been found to be predisposed to developing Parkinson's disease, and the risk of neoplasia associated with the disease is still subject to discussion. Disease-specific treatment consists of intravenous enzyme replacement therapy (ERT) using one of the currently available molecules (imiglucerase, velaglucerase, or taliglucerase). Orally administered inhibitors of glucosylceramide biosynthesis can also be used (miglustat or eliglustat).

Taliglucerase alfa in Gaucher disease: Description of a Brazilian experience

We evaluated retrospectively, efficacy and safety of taliglucerase alfa for Gaucher disease in a Brazilian population. Thirteen patients were included for efficacy analysis only one of them naïve to enzyme replacement therapy. All the parameters evaluated remained stable throughout treatment (mean duration 3,5years). Only three patients (out of 35) had to discontinue treatment due to a serious adverse event. In conclusion, treatment with taliglucerase alfa was found to be safe and efficient.

Design of a framework for the deployment of collaborative independent rare disease-centric registries: Gaucher disease registry model

Orphan drug clinical trials often are adversely affected by a lack of high quality treatment efficacy data that can be reliably compared across large patient cohorts derived from multiple governmental and country jurisdictions. It is critical that these patient data be captured with limited corporate involvement. For some time, there have been calls to develop collaborative, non-proprietary, patient-centric registries for post-market surveillance of aspects related to orphan drug efficacy. There is an urgent need for the development and sustainable deployment of these ‘independent’ registries that can capture comprehensive clinical, genetic and therapeutic information on patients with rare diseases. We therefore extended an open-source registry platform, the Rare Disease Registry Framework (RDRF) to establish an Independent Rare Disease Registry (IRDR). We engaged with an established rare disease community for Gaucher disease to determine system requirements, methods of data capture, consent, and reporting. A non-proprietary IRDR model is presented that can serve as autonomous data repository, but more importantly ensures that the relevant data can be made available to appropriate stakeholders in a secure, timely and efficient manner to improve clinical decision-making and the lives of those with a rare disease.

Evaluation of Bone Mineral Density in Patients with Type 1 Gaucher Disease in Argentina

The purpose of this study was to evaluate the frequency of osteoporosis (OP) in patients with Gaucher disease (GD) in Argentina. GD patients from 28 centers were consecutively included from April 2012 to 2014. Bone mineral density (BMD) was determined by dual X-ray absorptiometry in the lumbar spine and the femoral neck or the total proximal femur for patients ≥20 yr of age, and by whole-body scan in the lumbar spine in patients <20 yr of age. In children, mineral density was calculated using the chronological age and Z height. OP diagnosis was determined following adult and pediatric official position of the International Society for Clinical Densitometry. A total of 116 patients were included, of which 62 (53.5%) were women. The median age was 25.8 yr. All patients received enzyme replacement therapy, with a median time of 9.4 yr. Normal BMD was found in 89 patients (76.7%), whereas low bone mass (LBM) or osteopenia was found in 15 patients (13%) and OP in 12 patients (10.3%). The analysis of the pediatric population revealed that 4 patients (9.3%) had LBM and 3 (7%) had OP (Z-score ≤ -2 + fractures height-adjusted by Z), whereas in the adult population (n = 73), 11 patients (15%) had LBM or osteopenia and 9 (12.3%) had OP. Bone marrow infiltration and the presence of fractures were significantly correlated with the presence of OP (p = 0.04 and <0.001, respectively). This is the first study in Argentina and in the region describing the frequency of OP or LBM in GD patients treated with imiglucerase using the official position of the International Society for Clinical Densitometry.

Patients' perspectives on newborn screening for later-onset lysosomal storage diseases

Lysosomal storage diseases (LSDs) are an individually rare but collectively common group of hereditary, progressive, multi-systemic disorders. Recent technological advances have brought newborn screening (NBS) for LSDs to attention in the United States. However, many LSD symptoms present in later childhood or adulthood, with a wide spectrum of severity. Because late-onset symptoms stray from the traditional NBS model, healthcare providers have expressed concerns about potential harm to patients and/or their families. In this study, 47 individuals with Fabry disease (FD), 22 with Gaucher disease (GD), and 22 with late-onset Pompe disease (LOPD) were surveyed regarding how their life might have been impacted by NBS. Of the 91 participants, none had symptoms at birth and 42 (46.7%) were symptom-free until adulthood. Over half (52.8%) were diagnosed ≥5years from symptom onset; of these, significantly more had FD (60%) or LOPD (63.6%) than GD (23.8%). However, length of diagnostic odyssey was not significantly correlated with opinion on NBS. Most participants either strongly agreed (45%) or agreed (33.3%) with NBS for their condition, with no significant differences between diseases. Opinions on NBS were correlated with participants' opinions on whether NBS would have resulted in better current health, but uncorrelated with disease severity or current life satisfaction. Significantly more participants with FD (42.6%) and LOPD (63.6%) than GD (13.6%) felt they would have greater life satisfaction had they been diagnosed as a newborn (p=0.007). Almost half (41%) of participants would have made different life decisions, including lifestyle, financial, and reproductive decisions. Regarding potential harm, participants were most concerned about insurability and least concerned about removal of children's autonomy. In conclusion, NBS is highly approved of among individuals with LSDs themselves, as it would significantly eliminate diagnostic odysseys and potentially alter life planning.

Comorbidities and pharmacotherapies in patients with Gaucher disease type 1: The potential for drug-drug interactions

PURPOSE

Clinical care for patients with rare diseases may be complicated by comorbidities. Administration of medications to treat comorbidities may elicit potentially harmful drug-drug interactions (DDIs). Genetic background may also influence DDI occurrence. We investigated the range of comorbid conditions in patients with Gaucher disease type I (GD1), the pharmacotherapies prescribed and the potential for DDI with enzyme replacement and substrate reduction therapies and additional medications, specifically cytochrome P450 (CYP) metabolizing medications.

METHODS

A literature review examined comorbid conditions and pharmacotherapies reported in GD1. Analysis of two national databases reported real-world prescription practices in patients with GD1 (Germany, N=87; US, N=374). Prescribed drugs were assessed for known interactions with isoenzymes from the hepatic CYP enzyme family.

RESULTS

The literature reported GD1 symptomatology and comorbid conditions in broad agreement with the known clinical picture. German patients received 86 different medications whereas US patients received 329 different medications. An average of 3.2 medications (Germany) and 7 medications (US) per patient were prescribed. Moderate/strong inhibitors of CYP isoenzymes were prescribed to 20% and 57% of patients in the US and Germany, respectively.

CONCLUSION

This study describes the extensive number of comorbid conditions and drugs prescribed to patients with GD1, and the importance of determining CYP isoenzyme interaction to reduce DDI risk.

Patients with type 1 Gaucher disease in Spain: A cross-sectional evaluation of health status

A multicentre, cross-sectional epidemiological survey was conducted to describe the health status of patients with type 1 Gaucher disease (GD1) in Spain. Patient data were collected retrospectively from clinical records. Therapeutic goals for seven clinical parameters were chosen as primary outcome measures. 108 GD1 patients (mean age 44.8 years; 53% male) were recruited from 28 hospitals. Ninety-five patients (88%) were receiving treatment for GD1. Hemoglobin concentration was the therapeutic goal with the highest level of achievement, being met by 105 of 108 patients (97%), followed by the goals for liver volume (86/98 patients; 88%), spleen volume (67/77 patients; 87%) and platelet count (81/108 patients; 75%). The goal for bone mineral density (BMD) was met by 48 of 75 patients (64%), and the goal for quality of life was met by 65 of 103 patients (63%). Bone pain was the parameter with the lowest level of achievement (goal met by 50/94 patients; 53%). The clinical information most often missing from patient records was the BMD Z-score (missing for 31% of patients). These data suggest that most Spanish GD1 patients have good control over hematological and visceral parameters, but there is a need to improve monitoring and treatment of GD-related bone disease.

Gaucher disease in Syrian children: common mutations identification, and clinical futures

BACKGROUND AND OBJECTIVES

Gaucher disease (GD) is caused by the deficiency of glucosidase beta acid (GBA). Three clinical forms of GD are available. Some mutations in the GBA gene have a high frequency in spe.cific populations. The aim of this study was to analyze the characteristics of phenotypes and genotypes of GD in Syrian pediatric patients and assess whether a genotype-phenotype relationship could be helpful in treatment decision-making.

DESIGN AND SETTINGS

A cross-sectional clinical genetic study of 19 Syrian children admitted to Children's Hospital, Damascus University.

PATIENTS AND METHODS

Nineteen Syrian children with GD were enrolled in the study; DNA was extracted from peripheral blood leukocytes. The GBA gene was amplified by polymerase chain reaction, and the 9 most common mutations were studied using a Gaucher Disease Strip Assay (ViennaLab Diagnostics GmbH, Vienna, Austria).

RESULTS

The majority of children had an early age of onset. A total of17 patients presented severe hematological and skeletal complications. Neurological involvement was encountered in 2 patients. Twelve patients (63, 2%) were homozygous for the L444P mutation, 1 patient (5.3%) was homozygous for the N370S mutation, and 1 patient (5.3%) was heterozygous for the N370S mutation. Five patients (26.3%) had unknown mutations.

CONCLUSION

L444P/L444P was the most common genotype in the studied patients. GD3 with severe visceral presentation in childhood was the dominant phenotype; N370S was found in the heterozygote state in 1 case and in the homozygote state in 1 case. This phenotype and genotype pattern is encountered in the Middle East. There was no genotype-phenotype correlation.

Spectrum of GBA mutations in patients with Gaucher disease from Slovakia: identification of five novel mutations

BACKGROUND

Gaucher disease is the most common lysosomal storage disorder and is caused by a deficiency of the enzyme glucocerebrosidase. Enzyme deficiency leads to the accumulation of undegraded substrates, mainly in cells of the monocyte/ macrophage lineage, which is responsible for the clinical manifestations of the disease. To date, no study has attempted to identify the mutation spectrum of the glucocerebrosidase gene (GBA) in Slovak patients

OBJECTIVES

To identify mutations in 14 Slovak patients with confirmed glucocerebrosidase deficiency.

METHODS

Using molecular genetics methods PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) and direct sequencing of coding region GBA we identified the spectrum of mutations in our patients.

RESULTS

Five mutations (N370S, L444P, G377S, D409H and RecNciI) accounted for 75% of the mutant alleles. The remaining 25% were rare and probably individual mutations.

CONCLUSIONS

The mutational spectrum in our patients is similar to that observed in other European countries and corresponds to a Caucasian population, with N370S, L444P, RecNciI being the most common. Interestingly, mutation G377S was more frequent in our patients as compared to other published data. The C4W, L96P, H311N, 745delG and 1127_1128delTT mutations are described here for the first time in Gaucher disease, contributing to the panel of published GBA mutations.

An update of Gaucher mutations distribution in the Ashkenazi Jewish population: prevalence and country of origin of the mutation R496H

BACKGROUND

Gaucher disease is the most prevalent inherited disorder among Ashkenazi Jews (carrier frequency of about 6%) and six mutations account for about 96% of their mutant alleles. Two mutations, N370S and R496H, have been reported only in mildly affected or asymptomatic patients. Due to the rarity of R496H, it was recommended that it be excluded from screening programs.

OBJECTIVES

To verify the frequency and trace the origin of Gaucher mutations in screened individuals whose Ashkenazi ethnicity was confirmed by the birthplace of their grandparents.

METHODS

We conducted a retrospective analysis of the screened results for the period 2006-2011. Mutations were identified by restriction analysis, Tag-It detection system, Pronto diagnostic kit and Nanogen technology (NanoChip 400).

RESULTS

The heterozygote frequency of eight mutations was estimated in a cohort of 16,910 alleles. Two mutations, N370S and R496H, were the most frequent in our population. However, while the occurrence of N370S carriers was similar to other reports (1:19.4), that of R496H carriers was considerably elevated (1:207). Examination of the screened individuals' ethnicity showed a significant difference in the distribution pattern of the country of origin between the carriers of these two mutations.

CONCLUSIONS

The origin pattern differences between the two groups of heterozygotes might reflect a separate geographic region of introduction for various mutations. As a result, secondary subgroups could be formed within the Ashkenazi population. This might clarify the dissimilarities in the occurrence of R496H mutation reported by various centers.

The significance of GBA for Parkinson's disease

From the first descriptions of Parkinson's disease (PD) and Gaucher's disease (GD) in the nineteenth century, it took more than 100 years to discover the link between the GBA gene and Parkinsonism. The observation that mutations in the GBA gene represent the most common genetic risk factor for PD so far only came into focus because of astute clinical observation of Gaucher patients and their families. In this review, we (i) outline how GBA was identified as a genetic risk factor for Parkinsonism, (ii) present clinical characteristics of GBA-associated Parkinsonism, (iii) discuss possible mechanisms of the underlying pathogenesis in GBA-associated Parkinsonism, and (iv) provide an outlook on potentially new areas of research and treatment that arise from this important discovery.

Dynamic changes of lipid profile in Romanian patients with Gaucher disease type 1 under enzyme replacement therapy: a prospective study

BACKGROUND

Dyslipidemia in Gaucher disease includes reduced total, low-density lipoprotein (LDL)-, and high-density lipoprotein (HDL)-cholesterol (C). No prospective analysis of lipid profile changes in treatment-naïve patients under enzyme replacement therapy (ERT) is available.

METHODS

We analyzed lipid profile changes during ERT in a prospective controlled manner. Twelve treatment-naïve patients, Gaucher disease type 1 (GD1), 29.5 ± 12.9 years, 4M/8F. Diagnosis was made by enzymatic measurement and mutational analysis. Total-, LDL-, and HDL-C, triglycerides (TG), and LDL subfractions were assessed before the start of ERT with imiglucerase and biannually for 3 years. Patients were matched with healthy controls before and after 3 years of ERT.

RESULTS

At baseline, we found severely reduced HDL-C concentrations (23.6 ± 5.4 mg/dl) and enhanced LDL/HDL ratios (3.1 ± 0.7). HDL-C increased after 6 months (29.2 ± 5.7, p = 0.023), LDL/HDL ratio decreased after 30 months (2.5 ± 0.5, p = 0.039). TG, even not consistently enhanced at baseline (128 ± 31.3 mg/dl), yet higher than in controls (p < 0.001), decreased after 18 months, being comparable with controls after 3 years of ERT. Small, dense LDL (mg/dl) increased continuously without significant difference to controls. After 3 years of ERT, only reduced HDL-C concentrations persisted as a potentially atherogenic alteration; however, mean concentrations markedly improved (42.9 ± 8.3 mg/dl, p < 0.001). Lipid parameters correlated with six markers of disease severity.

CONCLUSIONS

This is the first prospective controlled study regarding lipid profile dynamics during ERT (glucocerebrosidase) in initially treatment-naïve GD1 patients. The most important changes were reduced HDL-C and enhanced LDL/HDL ratio. Their dynamics during ERT and correlations with markers of disease activity suggest that they can be considered markers of disease severity and follow-up in Gaucher patients under treatment.

Long-term clinical outcomes in type 1 Gaucher disease following 10 years of imiglucerase treatment

OBJECTIVE

We studied the effect of long-term alglucerase/imiglucerase (Ceredase®/Cerezyme®, Genzyme, a Sanofi company, Cambridge, MA, USA) treatment on hematological, visceral, and bone manifestations of Gaucher disease type 1 (GD1).

METHODS

The International Collaborative Gaucher Group (ICGG) Gaucher Registry identified GD1 patients treated with alglucerase/imiglucerase who had dose and clinical data at first infusion and after 10 years of follow-up. Data for hemoglobin, platelet count, organ volumes, bone pain, and bone crisis were analyzed. Tests of the null hypothesis (no change from first infusion to 10 years) were performed using t tests for within-patient absolute change in continuous measurements and McNemar/chi-square tests for change in distributions using categorical values. An alpha level of 0.05 designated statistical significance.

RESULTS

As of October 2011, 557 nonsplenectomized and 200 splenectomized patients met the inclusion criteria. The majority of GD1 patients had at least one N370S allele. Compared with nonsplenectomized patients at first infusion, splenectomized patients had lower percentages of anemia (26.0 % vs. 42.8 %) and thrombocytopenia (14.2 % vs. 76.3 %), similar percentages of moderate or severe hepatomegaly (81.2 % vs. 80.0 %), and higher percentages of bone pain (88.9 % vs. 52.4 %) and bone crises (38.3 % vs. 16.0 %). After 10 years, both groups showed significant (p < 0.05) improvements in mean hemoglobin levels, platelet count, liver, and spleen (nonsplenectomized) volumes, and bone crises. Initial dosing in both groups ranged from <15 U/kg to ≤90 U/kg every 2 weeks. After 10 years, the majority was receiving 15 to ≤45 U/kg every 2 weeks.

CONCLUSION

Ten years of imiglucerase treatment results in sustainable improvements in all GD1 parameters.

Ultramicro-fluorometric assay for the diagnosis of Gaucher disease in dried blood spots on filter paper

BACKGROUND

Gaucher disease (GD) is a lysosomal storage disorder characterized by a deficiency of the lysosomal acid β-D-glucosidase (GBA). The aim of this study was to develop an ultramicro-fluorometric assay based on the method of Chamoles et al. for determining GBA activity in dried blood spots on filter paper (DBS).

METHODS

The assay used 3-mm diameter blood spot and 8 mmol/l of 4-methylumbelliferyl-β-D-glucoside as enzymatic substrate. The reaction occurred in plates incubated at 37°C for 20 hours and the enzyme activity was expressed in μmol hydrolysed substrate/l blood/h. The fluorescence of the enzyme product was automatically measured in a fluorometer-photometer reader (SUMA Technology).

RESULTS

The intra and inter-assay coefficients of variation were lower than 9 and 12%, respectively, and the recovery range was 97-109%.Three patients with GD were correctly diagnosed using the ultramicroassay. Healthy newborn DBS samples (n = 3003) from the National Neonatal Screening Program were analyzed, and the mean GBA activity was 5.7 μmol/l blood/h. Our assay showed high Pearson (n = 26; r = 0.99) and concordance correlations (ρc = 0.99) with the traditional method described by Chamoles et al.

CONCLUSIONS

The analytical performance characteristics of our ultramicro-fluorometric assay suggest that it can be used in the diagnosis of GD in newborns and adults.

[Gaucher disease in Latin America. A report from the Gaucher Disease International Registry and the Latin American Group for Gaucher Disease]

Gaucher disease -due to its low frequency- is considered an orphan disease. In 1991 the International Gaucher Registry was created and in 1992 the first patients from Latin America were enrolled. In 2008 the Latin American Group for Gaucher Disease was initiated. Its main objectives are to promote regional consensus, to stimulate the enrollment of patients into the International Gaucher Registry and the enhancement of knowledge on this disease, and to achieve better care and quality of life of patients in our Region. Until April 2010, 5828 patients have been enrolled all around the world, 911 (15.6%) from Latin America. This is the first comprehensive report of the disease in the Region. In our population there is a predominance of females, the most common clinical form is the type I (95%) and the age at diagnosis is before 20 years in 68% of patients. The most frequent clinical manifestations at diagnosis are splenomegaly (96%) and anemia (49%). Eighty percent of patients had radiographic findings of bone involvement. In our Region, the vast majority of patients (89%) had received enzyme replacement therapy with imiglucerase; with a long follow-up (up to 10 years) they have achieved the therapeutic goals, showing the great effectiveness of therapy. While the percentage of patients with therapy is high, discontinuations are common. The main deficiencies in our Region are: the lack of visceral volumetric evaluations and densitometries as well as molecular analysis for some patients. The main problem is the under-diagnosis of patients.

Four-year follow-up of chronic neuronopathic Gaucher disease in Europeans using a modified severity scoring tool

In 2007, the European Task Force for neuronopathic Gaucher disease (NGD) published a review of 55 patients across four countries. Although some observations were possible, analysis was difficult due to the absence of a systematic way of assessing patients. In response to this, a Severity Scoring Tool (SST) was devised to offer a systematic means of assessing the neurological presentation seen. The SST has been modified (mSST) and is a valid tool for monitoring neurological progression. This review describes disease status and progression of neurological manifestations in a cohort of 39 chronic NGD patients across three European countries over a period of 4 years, using the mSST.

Gastrointestinal disturbances and their management in miglustat-treated patients

Miglustat (Zavesca®) is approved for the oral treatment of adult patients with mild to moderate type 1 Gaucher disease (GD1) for whom enzyme replacement therapy is unsuitable, and for the treatment of progressive neurological manifestations in adult and paediatric patients with Niemann-Pick disease type C (NP-C). Gastrointestinal disturbances such as diarrhoea, flatulence and abdominal pain/discomfort have consistently been reported as the most frequent adverse events associated with miglustat during clinical trials and in real-world clinical practice settings. These adverse events are generally mild or moderate in severity, occurring mostly during the initial weeks of therapy. The mechanism underlying these gastrointestinal disturbances is the inhibition by miglustat of intestinal disaccharidase enzymes (mainly sucrase and maltase), leading to sub-optimal hydrolysis of carbohydrates and subsequent osmotic diarrhoea and altered colonic fermentation. Transient decreases in body weight, which are often observed during initial miglustat therapy, are considered likely due to gastrointestinal carbohydrate malabsorption and associated negative caloric balance. While most cases of diarrhoea resolve spontaneously during continued miglustat therapy, diarrhoea also responds well to anti-propulsive medications such as loperamide. Dietary modifications such as reduced consumption of dietary sucrose, maltose and lactose have been shown to improve the gastrointestinal tolerability of miglustat and reduce the magnitude of any changes in body weight, particularly if initiated at or before the start of therapy. Miglustat dose escalation at treatment initiation may also reduce gastrointestinal disturbances. This article discusses these aspects in detail, and provides practical recommendations on how to optimize the gastrointestinal tolerability of miglustat.

Reducing selection bias in case-control studies from rare disease registries

BACKGROUND

In clinical research of rare diseases, where small patient numbers and disease heterogeneity limit study design options, registries are a valuable resource for demographic and outcome information. However, in contrast to prospective, randomized clinical trials, the observational design of registries is prone to introduce selection bias and negatively impact the validity of data analyses. The objective of the study was to demonstrate the utility of case-control matching and the risk-set method in order to control bias in data from a rare disease registry. Data from the International Collaborative Gaucher Group (ICGG) Gaucher Registry were used as an example.

METHODS

A case-control matching analysis using the risk-set method was conducted to identify two groups of patients with type 1 Gaucher disease in the ICGG Gaucher Registry: patients with avascular osteonecrosis (AVN) and those without AVN. The frequency distributions of gender, decade of birth, treatment status, and splenectomy status were presented for cases and controls before and after matching. Odds ratios (and 95% confidence intervals) were calculated for each variable before and after matching.

RESULTS

The application of case-control matching methodology results in cohorts of cases (i.e., patients with AVN) and controls (i.e., patients without AVN) who have comparable distributions for four common parameters used in subject selection: gender, year of birth (age), treatment status, and splenectomy status. Matching resulted in odds ratios of approximately 1.00, indicating no bias.

CONCLUSIONS

We demonstrated bias in case-control selection in subjects from a prototype rare disease registry and used case-control matching to minimize this bias. Therefore, this approach appears useful to study cohorts of heterogeneous patients in rare disease registries.

Neurological manifestations in patients with Gaucher disease and their relatives, it is just a coincidence?

Gaucher disease (GD) is an autosomal recessive disorder characterized by defective function of glucocerebrosidase. GD presents a wide spectrum of manifestations, and patients and their relatives may develop neurological abnormalities more frequently than the general population. This study aims to determine the presence of neurological symptoms (NS) and Parkinson's disease (PD) in Spanish GD patients and their relatives. We surveyed 87 GD Spanish families and validated the information obtained on the neurological involvement through their physicians, as well as the historical data included in the Spanish Gaucher Disease Registry. Neurological abnormalities were correlated with the genetic characteristics. Statistical analyses included descriptive parameters, ANOVA, t-test, correlation study and Pearson coefficient. Information was obtained from 118 patients and 324 relatives. Out of 110 patients with type 1 GD, 32 (29.1%) reported NS and 7 (6.4%) had PD. In relatives, a total of 39 (13.1%) subjects had NS, including 16 with PD (5.3%). The prevalence of NS in genetic carriers (15.9%) was greater than that in non-carriers (5.9%; p < 0.01). Patients with PD carried the following GBA mutations: S364R, D409H, L444P, R257Q, IVS4-2A > G, c.500insT, and L336P. Relatives with PD exhibited a wide spectrum of mutations: L444P, N370S, V398I, R257Q, G202R, c.1439-1445del7, [E326K; N188S], and c.953delT. We observed a high incidence of PD in type 1 GD and relative's carriers. PD was more frequent in carriers of L444P and other rare GBA mutations. Therefore, it is important to perform a systematic neurological exam in patients with type 1 GD and carriers with high risk mutations.

General knowledge and awareness on rare diseases among general practitioners in Bulgaria

Rare diseases are a serious public health problem and are a threat to the health of EU citizens. Important role in the area of rare diseases have the medical specialists who diagnose and monitor the course of the disease of each patient. General practitioners (GPs) are usually the first to identify "unusual" patients that might have a rare disease. The GPs awareness and knowledge about rare diseases is a strong factor for the timely and accurate diagnosis and adequate treatment of rare diseases conditions. A telephone interview was conducted among the GPs in Bulgaria between January and March 2008. A set of 10 questions with pre-defined answers was constructed and offered to the GPs in order to determine their level of knowledge and awareness of rare diseases. Data were statistically processed using specialized software SPSS version 9.0 (SPSS, Inc., Chicago IL). The responses of surveyed doctor indicate a low level of general knowledge and awareness. This means, that GPs from the primary health care system in Bulgaria could not provide sufficient in quality and timeliness specific information to their patients with rare diseases. A campaign for increasing the awareness of GPs about rare diseases is needed.

Vertebral fractures in Gaucher disease type I: data from the French "Observatoire" on Gaucher disease (FROG)

Gaucher disease type 1 (GD1), results in a range of skeletal complications including osteopenia, osteoporosis, and osteonecrosis, but there is little published information regarding vertebral fractures. Findings from this observational study indicated that the prevalence of vertebral fractures in a cohort of adult French GD1 patients is approximately 15%.

INTRODUCTION

The aim of the study was to assess the prevalence and characteristics of vertebral fractures in a cohort of adult patients with GD1.

METHODS

This study was performed in adult patients with GD1 based on a detailed and complete clinical examination. For all patients for whom vertebral fractures were reported, a specific questionnaire was sent to physicians, and imaging data were collected, when available, for centralized analysis.

RESULTS

Data were collected from a total of 105 adult GD1 patients. Bone complications were reported in 85% of patients, among whom vertebral fractures were diagnosed in 16 (15%); seven women and nine men (mean age, 45 years). We observed five patients with multiple vertebral fractures and one patient in whom the T3 vertebra was fractured. Most of these patients did not report fracture-related back pain.

CONCLUSIONS

The prevalence of vertebral fractures in this cohort of adult patients with GD1 was 15%. Greater awareness of the natural history of vertebral fractures in GD1, and rigorous monitoring of bone fragility and spine involvement in affected patients, should allow earlier detection and initiation of treatment tailored toward improving bone status.

Osseous manifestations of adult Gaucher disease in the era of enzyme replacement therapy

Enzyme replacement therapy (ERT) for Gaucher disease with mannose-terminated glucocerebrosidase has proved its therapeutic position with salutary effects on hematologic abnormalities, visceral infiltration, and quality of life. The frequency of new bone complications is reduced but not eliminated. Established osteonecrosis is beyond salvage. A systematic description of the burden of bone manifestations, persisting despite ERT, should inform future remedial strategies. Thus, we conducted this study to quantify the burden of residual skeletal disease and to explore putative relationships between clinical, radiologic, and biochemical factors and bone sequelae associated with disability.Consecutive adult patients attending 3 referral centers in the United Kingdom were invited to participate. A representative group of 100 patients agreed to a structured interview, clinical examination, radiologic review, and completion of questionnaires. Osteonecrosis was evident in 43%, Erlenmeyer flask deformity in 59%, fragility fracture in 28%, osteomyelitis in 6%, and lytic lesions in 4%. Mobility was impaired in 32% of patients, while 15% experienced significant pain. The EuroQol 5D (EQ5D) quality of life summary measure was reduced and was associated with osteonecrosis and fragility fracture. Eight patients experienced new osteonecrosis after the start of ERT, though the presentation and evolution were often atypical. Nine patients had been treated from childhood and had an excellent outcome. Osteonecrosis was associated with age of presentation and with splenectomy-indeed, we observed a strong temporal association between splenectomy and incidence of osteonecrosis.The biomarkers PARC/CCL18 and chitotriosidase were associated with prevalent osteonecrosis, and, in particular, with osteonecrosis occurring despite treatment. This study documents significant residual skeletal pathology and disability in patients in the mature phase of their treatment in a developed region. The temporal association between splenectomy and osteonecrosis implies causation. The relationship between clinical and biochemical markers and existing bone complications sets the scene for future prospective studies that will focus on management strategies informed by credible assessment of risk.

Gaucher's disease in Lithuania: its diagnosis and treatment

Gaucher's disease is a lysosomal storage disease caused by the lack of beta-glucocerebrosidase enzyme, leading to the accumulation of glucocerebroside. Gaucher's disease is the most frequent type of sphingolipidosis as well as the most frequent lysosomal disease. Clinically, two forms of Gaucher's disease are defined: nonneuronopathic form, so-called type 1, characterized by hepatosplenomegaly, thrombocytopenia, anemia, and osteopenia, and neuronopathic form, known as types 2 and 3, which are also characterized by hepatosplenomegaly, hematological and bone changes; however, involvement of the central nervous system dominates in the clinical picture. Severe deficiency of beta-glucocerebrosidase activity allows confirming the diagnosis based on the clinical picture or the findings of bone marrow examination. Treatment with human glucocerebrosidase was introduced in 1991. Clinically good results are achieved: not only accumulation of glucocerebroside is stopped, but also positive changes in the reticuloendothelial system and an improvement in development and hematological parameters of children are observed as well as the development of bone lesions is reduced. To date, Gaucher's disease has been diagnosed in 8 patients in Lithuania: 3 persons have type 3 and 5 have type 1 disease. Enzyme replacement therapy was started in 2001, and currently 6 persons are being treated. In majority of patients, Gaucher's disease was suspected after exclusion of other possible proliferative diseases. All patients within the first or second year of treatment achieved the therapeutic goals, namely: normalization of hematological parameters, reduction in liver and spleen volumes, and bone pain relief.

The neurological manifestations of Gaucher disease type 1: the French Observatoire on Gaucher disease (FROG)

BACKGROUND

Gaucher disease (GD), the most prevalent inherited lysosomal storage disorder, is caused by deficient glucocerebrosidase activity. Type 1 GD (GD1), the most common variant, is classically considered non-neuronopathic.

METHODS

We performed a national cross-sectional observational survey-the French Observatoire on Gaucher Disease (FROG)-in patients with GD1 between March 2005 and September 2006. The study included all patients over 18 years of age with confirmed GD1 who attended participating centers for regular follow-up.

RESULTS

One hundred and five patients were included, in whom we studied the prevalence and characteristics of relevant neurological symptoms associated with the neuraxis. Of these, 51 (49%) GD1 patients presented at least one neurological symptom. Four patients (4%) had Parkinson disease and 22 (21%) presented with at least one parkinsonian sign or at least one sign frequently associated with Parkinson disease. Five patients (5%) had a previous diagnosis of peripheral neuropathy. Other central nervous system symptoms were recorded in 20 (19%) patients and other peripheral nervous system symptoms in 39 (37%) patients.

CONCLUSIONS

These data challenge the current classification of GD, and suggest that the three forms of GD each involve a different profile of neurological manifestations.

Neuronopathic Gaucher disease: demographic and clinical features of 131 patients enrolled in the International Collaborative Gaucher Group Neurological Outcomes Subregistry

OBJECTIVE

To describe demographic, genetic, and clinical characteristics of patients with neuronopathic Gaucher disease (NGD).

METHODS

All patients enrolled in the Neurological Outcomes Subregistry of the International Collaborative Gaucher Group (ICGG) Gaucher Registry as of June 2007 were identified.

RESULTS

The study cohort comprised 131 patients from 17 countries who were enrolled in the Neurological Outcomes Subregistry. The onset of neurological manifestations had occurred before 2 years of age in 47% (61 out of 131 patients), 2 years of age or older in 41% (54 out of 131), and could not be ascertained in the remaining 12% (16 out of 131). The most common manifestations were inability to look to the extreme up or down (45%, 55 out of 123), abnormally slow object tracking (43%, 53 out of 123), convergent squint (36%, 44 out of 121), and ataxia (15 to 20%, 18-27 out of 117). Seizures were reported in 19 out of 122 patients (16%), and myoclonic seizures were reported in 3 out of 121 patients (2%). The most common genotypes were L444P/L444P (76 out of 108, 70%), L444P/D409H (9 out of 108, 8%), D409H/D409H (8 out of 108, 7%), and L444P/rare allele (6 out of 108, 6%); full sequencing was not performed in all patients.

CONCLUSIONS

Neurological manifestations of GD often begin to appear before the age of 2 years. The most common neurological signs and manifestations are brainstem abnormalities and fine motor dysfunction. The most common genotype is L444P/L444P.

High incidence of cholesterol gallstone disease in type 1 Gaucher disease: characterizing the biliary phenotype of type 1 Gaucher disease

BACKGROUND

In Gaucher disease (GD), lysosomal glucocerebrosidase deficiency results in glucosylceramide accumulation in macrophage lysosomes. Hepatocytes do not accumulate glucosylceramide due in part to biliary secretion. Although gallstones (GS) occur in type 1 Gaucher disease (GD1), the chemical nature of stones, their association with metabolic parameters, and whether bile composition is altered are not understood. We assessed the prevalence of GS, their chemical composition, biliary lipids, and associated metabolic factors.

METHODS

The study cohort comprised 417 patients comprehensively evaluated for GD1 severity. Ascertainment of GS, fasting lipoprotein profile, and bile lipid analyses were performed.

RESULTS

The prevalence of GS in GD1 was 32%. Compared with men, the prevalence of GS was higher in women, increasing from 4.2% and 11.8% at age 20-29 years to 71% and 60% at age >70 years, respectively. Patients with GS were more likely to be asplenic (p < 0.0001), older (p < 0.0001), have higher low-density lipoprotein (LDL) cholesterol (p = 0.002), and more severe GD1 disease compared with those without GS. On multiple logistic regression analysis, factors associated with GS were age (p < 0.001), female sex (p = 0.03), and splenectomy (p = 0.005). Compared with the general population, prevalence of GS was approximately 5-fold higher. Bile lipid analyses revealed cholesterol stones in five patients and pigment stones in one. Bile lipid composition was abnormal and contained glucosylceramide.

CONCLUSIONS

Our results point to a metabolic syndrome in GD1 consisting of a propensity to cholesterol GS, low high-density lipoprotein (HDL) cholesterol, LDL cholesterol, and body mass index (BMI) associated with abnormal biliary lipid secretion.

The risk of Parkinson's disease in type 1 Gaucher disease

In Gaucher disease, defective lysosomal glucocerebrosidase due to mutations in the GBA1 gene results in lysosomal accumulation of glucocerebroside in mononuclear phagocytes and a multisystemic phenotype. Observations of occurrence of Parkinson's disease in some patients with non-neuronopathic type 1 Gaucher disease (GD1) and their first degree relatives has led to the identification of GBA1 heterozygous mutations as a genetic risk factor for idiopathic Parkinson's disease (PD). However, the magnitude of risk of PD in patients with known GD1 has not been determined, and it is not known whether GD1/PD represents a specific sub-phenotype of GD1 with distinctive genotype/phenotype characteristics. We estimated the risk of PD in a cohort of 444 consecutively evaluated patients with GD1 compared to that in the general population. Eleven patients developed parkinsonian syndrome during a 12-year follow-up period. The adjusted life-time risk ratio of PD in GD1 compared to that in the general population was 21.4 [95% confidence interval (95% CI) 10.7-38.3], with a higher risk in men compared to women. In our cohort, GD1/Parkinson's disease phenotype (GD1/PD) was characterized by higher GD1 severity score, due to higher incidence of avascular osteonecrosis. The clinical spectrum of PD varied from mild to potentially life-threatening disease. All but one patient with GD1/PD phenotype had at least one N370S GBA1 allele. In conclusion, compared to the general population, patients with GD1 have an almost 20-fold increased life-time risk of developing PD.

[An analysis of mutations causing Gaucher disease in Chinese population]

OBJECTIVE

To review and investigate the relationship of genotype and phenotype in Chinese patients with Gaucher disease (GD).

METHODS

The samples were first screened for known mutations as reported previously in Chinese population. Long chain PCR and nested PCR were employed to amplify the segments of glucocerebrosidase functional gene in patients with unknown mutant alleles. The products of nested-PCR were subjected to DNA sequencing to detect the new mutations.

RESULTS

Forty kinds of mutations were detected in this panel of patients. The L444P mutation was the most common one accounting for 33.0% of mutant alleles. It was followed by F213I, N188S, V375L and M416V.

CONCLUSION

There are at least 40 mutations in Chinese GD patients. The spectrum of mutation is significantly different from that in Caucasians. 70% of mutant alleles have been characterized. It becomes feasible to make clinical and prenatal diagnoses through gene analysis.

The underrecognized progressive nature of N370S Gaucher disease and assessment of cancer risk in 403 patients

Mutations in GBA1 gene that encodes lysosomal glucocerebrosidase result in Type 1 Gaucher Disease (GD), the commonest lysosomal storage disorder; the most prevalent disease mutation is N370S. We investigated the heterogeneity and natural course of N370S GD in 403 patients. Demographic, clinical, and genetic characteristics of GD at presentation were examined in a cross-sectional study. In addition, the relative risk (RR) of cancer in patients compared with age-, sex-, and ethnic-group adjusted national rates of cancer was determined. Of the 403 patients, 54% of patients were homozygous (N370S/N370S) and 46% were compound heterozygous for the N370S mutation (N370S/other). The majority of N370S/N370S patients displayed a phenotype characterized by late onset, predominantly skeletal disease, whereas the majority of N370S/other patients displayed early onset, predominantly visceral/hematologic disease, P < 0.0001. There was a striking increase in lifetime risk of multiple myeloma in the entire cohort (RR 25, 95% CI 9.17-54.40), mostly confined to N370S homozygous patients. The risk of other hematologic malignancies (RR 3.45, 95% CI 1.49-6.79), and overall cancer risk (RR 1.80, 95% CI 1.32-2.40) was increased. Homozygous N370S GD leads to adult-onset progressive skeletal disease with relative sparing of the viscera, a strikingly high risk of multiple myeloma, and an increased risk of other cancers. High incidence of gammopathy suggests an important role of the adaptive immune system in the development of GD. Adult patients with GD should be monitored for skeletal disease and cancers including multiple myeloma.