Exploring the patient journey to diagnosis of Gaucher disease from the perspective of 212 patients with Gaucher disease and 16 Gaucher expert physicians

Capturing Real-World Rare Disease Patient Journeys: Are Current Methodologies Sufficient for Informed Healthcare Decisions?

RATIONALE

Despite growing emphasis among healthcare decision-makers on patient perspectives and real-world outcomes to inform care and access decisions, understanding of patient journey experiences in rare diseases remains limited due to data collection and evaluation challenges.

AIMS AND OBJECTIVES

This systematic literature review (SLR) assessed study designs, methodologies, and outcomes reported in real-world investigations of rare disease patient journeys.

METHODS

Searches in PubMed and Google Scholar targeted English-language publications and congress proceedings from 1 January 2014, to 30 April 2024, including rare disease patients, caregivers, or healthcare providers. Keywords included 'Journey', 'Path', or 'Odyssey'. Two reviewers independently assessed eligibility and abstracted data. Descriptive analyses and quality assessments were conducted.

RESULTS

Thirty-one studies met inclusion criteria, with 296,548 participants spanning over 600 rare diseases. Most studies used prospective observational (61%) and cross-sectional (26%) designs and were conducted in Europe (45%). Interviews (39%) and surveys (29%) were common methodologies. Patients (87%) were the primary research focus, compared to caregivers (32%) or providers (10%). The most studied journey stages were 'Pre-diagnosis/Screening' (97%) and 'Diagnosis' (84%), while 'Disease Awareness' (16%) and 'Treatment Adherence' (6%) were less common. Across 164 outcomes reported, frequent outcomes included 'Healthcare Resource Utilization' (94%), 'Symptoms' (74%), and 'Time-to-Diagnosis' (71%). Fewer studies reported 'Costs' (19%), 'Caregiver/Family Burden' (16%), and 'Productivity' (13%). Time-to-diagnosis averaged 11.8 years and a median of 6.1 years. All but one study (97%) was rated low or very low quality due to observational designs.

CONCLUSION

Most rare disease patient journey evidence focuses on 'Pre-diagnosis/Screening' and 'Diagnosis' stages using qualitative methods and surveys. While symptoms, time-to-diagnosis, and resource utilization were commonly reported, evidence gaps included treatment adherence, caregiver burden and productivity. Longitudinal assessments to collect real-world care and treatment burden outcomes, including caregiver perspectives, can enhance both clinician and policy decision-making for individuals living with rare diseases.

Obstacles to Early Diagnosis of Gaucher Disease

Gaucher disease (GD) is a rare lysosomal storage disorder resulting from a deficiency of the lysosomal enzyme glucocerebrosidase caused by biallelic variants in the GBA1 gene. Patients may present with a wide spectrum of disease manifestations, including hepatosplenomegaly, thrombocytopenia, bone manifestations, and in the case of GD types 2 and 3, neurodegeneration, cognitive delay, and/or oculomotor abnormalities. While there is no treatment for neuronopathic GD, non-neuronopathic manifestations can be efficiently managed with enzyme replacement therapy or substrate reduction therapy. However, many patients with GD experience a lengthy diagnostic odyssey, which can negatively affect their access to care and clinical outcomes. The cause of this diagnostic delay is multifaceted. Since genotype/phenotype correlations in GD are not always clear, it is difficult to predict the presence, severity, and onset of clinical manifestations. This heterogeneity, combined with the molecular complexity of the GBA1 locus, low disease prevalence, and limited knowledge of GD among providers serves as a barrier to early diagnosis of GD. In this review, we discuss such obstacles and challenges, considerations, and future steps toward improving the diagnostic journey for patients with GD.

The Unmet Needs of Lysosomal Storage Disorders from Early Diagnosis to Caregiving Pathways: An Italian Perspective

Background/Objective: Lysosomal storage diseases (LSDs) are a group of rare, inborn, metabolic errors characterized by deficiencies in normal lysosomal function and by the intralysosomal accumulation of undegraded substrates, resulting in the damage of multiple organ systems. The spectrum of clinical manifestations is extremely heterogeneous. LSD diagnosis and management still present many issues. Methods: A group of Italian experts and patients' representatives met to discuss some critical aspects, and among the most impactful are early diagnosis, the transition of the patient from pediatric to adult age, territorial management, and the multidisciplinary approach. Results: Possible solutions to diagnostic delays may be a widespread newborn screening and screening programs on selected populations. The lack of a structured transition process could be helped by the drafting of shared diagnostic and therapeutic care pathways beyond the availability of databases accessible to the different levels that manage a patient. Territorial management could benefit from telemedicine, but a homogeneous diffusion of home therapy, not yet everywhere possible, is essential. A fundamental role is played by the patient associations, which should be increasingly involved in the political choices. It is also crucial to create structured multidisciplinary teams of experts for disease management and comorbidities. A transversal need appears to be greater training on LSDs. In Italy, the "Statement of Udine" was developed to guide further steps towards improvements in inherited metabolic medicine in adults, referencing the experience from the United Kingdom. Conclusions: Much can be done for the early diagnosis and management of LSDs with an effective treatment, but many aspects need improvement for the overall management of the patient. An investment in dedicated resources, formal recognition, and training is needed to address these unmet needs.

A machine learning model for early diagnosis of type 1 Gaucher disease using real-life data

OBJECTIVE

The diagnosis of Gaucher disease (GD) presents a major challenge due to the high variability and low specificity of its clinical characteristics, along with limited physician awareness of the disease's early symptoms. Early and accurate diagnosis is important to enable effective treatment decisions, prevent unnecessary testing, and facilitate genetic counseling. This study aimed to develop a machine learning (ML) model for GD screening and GD early diagnosis based on real-world clinical data using the Maccabi Healthcare Services electronic database, which contains 20 years of longitudinal data on approximately 2.6 million patients.

STUDY DESIGN AND SETTING

We screened the Maccabi Healthcare Services database for patients with GD between January 1998 and May 2022. Eligible controls were matched by year of birth, sex, and socioeconomic status in a 1:13 ratio. The data were partitioned into 75% training and 25% test sets and trained to predict GD using features obtained from medical and laboratory records. Model performances were evaluated using the area under the receiver operating characteristic curve and the area under the precision-recall curve.

RESULTS

We detected 264 confirmed patients with GD to which we matched 3,429 controls. The best model performance (which included known GD signs and symptoms, previously unknown clinical features, and administrative codes) on the test set had an area under the receiver operating characteristic curve = 0.95 ± 0.03 and area under the precision-recall curve = 0.80 ± 0.08, which yielded a median GD identification of 2.78 years earlier than the clinical diagnosis (25th-75th percentile: 1.29-4.53).

CONCLUSION

Using an ML approach on real-world data led to excellent discrimination between GD patients and controls, with the ability to detect GD significantly earlier than the time of actual diagnosis. Hence, this approach might be useful as a screening tool for GD and lead to earlier diagnosis and treatment. Furthermore, advanced ML analytics may highlight previously unrecognized features associated with GD, including clinical diagnoses and health-seeking behaviors.

Adult type I Gaucher disease with splenectomy caused by a compound heterozygous GBA1 mutation in a Chinese patient: a case report

Gaucher disease (GD) is an autosomal recessive ailment resulting from glucocerebrosidase deficiency caused by a mutation in the GBA1 gene, leading to multi-organ problems in the liver, spleen, and bone marrow. In China, GD is extremely uncommon and has a lower incidence rate than worldwide. In this study, we report the case of an adult male with an enlarged spleen for 13 years who presented with abdominal distension, severe loss of appetite and weight, reduction of the three-line due to hypersplenism, frequent nosebleeds, and bloody stools. Regrettably, the unexpected discovery of splenic pathology suggestive of splenic Gaucher disease was only made after a splenectomy due to a lack of knowledge about rare disorders. Our patient's delayed diagnosis may have been due to the department where he was originally treated, but it highlights the need for multidisciplinary consultation in splenomegaly of unknown etiology. We then investigated the patient's clinical phenotypes and gene mutation features using genetically phenotypical analysis. The analysis of the GBA1 gene sequence indicated that the patient carried a compound heterozygous mutation consisting of two potentially disease-causing mutations: c.907C > A (p. Leu303Ile) and c.1448 T > C (p. Leu483Pro). While previous research has linked the p. Leu483Pro mutation site to neurologic GD phenotypes (GD2 and GD3), the patients in this investigation were identified as having non-neuronopathic GD1. The other mutation, p. Leu303Ile, is a new GD-related mutation not indexed in PubMed that enriches the GBA1 gene mutation spectrum. Biosignature analysis has shown that both mutations alter the protein's three-dimensional structure, which may be a pathogenic mechanism for GD1 in this patient.

Assessing the diagnostic utility of the Gaucher Earlier Diagnosis Consensus (GED-C) scoring system using real-world data

BACKGROUND

Gaucher disease (GD) is a rare autosomal recessive condition associated with clinical features such as splenomegaly, hepatomegaly, anemia, thrombocytopenia, and bone abnormalities. Three clinical forms of GD have been defined based on the absence (type 1, GD1) or presence (types 2 and 3) of neurological signs. Early diagnosis can reduce the likelihood of severe, often irreversible complications. The aim of this study was to validate the ability of factors from the Gaucher Earlier Diagnosis Consensus (GED-C) scoring system to discriminate between patients with GD1 and controls using real-world data from electronic patient medical records from Maccabi Healthcare Services, Israel's second-largest state-mandated healthcare provider.

METHODS

We applied the GED-C scoring system to 265 confirmed cases of GD and 3445 non-GD controls matched for year of birth, sex, and socioeconomic status identified from 1998 to 2022. The analyses were based on two databases: (1) all available data and (2) all data except free-text notes. Features from the GED-C scoring system applicable to GD1 were extracted for each individual. Patients and controls were compared for the proportion of the specific features and overall GED-C scores. Decision tree and random forest models were trained to identify the main features distinguishing GD from non-GD controls.

RESULTS

The GED-C scoring distinguished individuals with GD from controls using both databases. Decision tree models for the databases showed good accuracy (0.96 [95% CI 0.95-0.97] for Database 1; 0.95 [95% CI 0.94-0.96] for Database 2), high specificity (0.99 [95% CI 0.99-1]) for Database 1; 1.0 [95% CI 0.99-1] for Database 2), but relatively low sensitivity (0.53 [95% CI 0.46-0.59] for Database 1; 0.32 [95% CI 0.25-0.38]) for Database 2). The clinical features of splenomegaly, thrombocytopenia (< 50 × 109/L), and hyperferritinemia (300-1000 ng/mL) were found to be the three most accurate classifiers of GD in both databases.

CONCLUSION

In this analysis of real-world patient data, certain individual features of the GED-C score discriminate more successfully between patients with GD and controls than the overall score. An enhanced diagnostic model may lead to earlier, reliable diagnoses of Gaucher disease, aiming to minimize the severe complications associated with this disease.

Uncovering a New Family Cluster of Gaucher Disease: A Case Report

Gaucher disease (GD) is a recessive autosomal lysosomal storage disorder caused by a deficiency in glucocerebrosidase, leading to the accumulation of undigested glycolipids in the lysosomes of monocytes and macrophages. Patients with GD exhibit a spectrum of phenotypic heterogeneity and are broadly classified into three subtypes. Type 1 is the most common and is not associated with neurological damage, while types 2 and 3 are more severe, presenting with acute neuropathic and subacute neuropathic symptoms, respectively. A thorough accurate initial multisystemic assessment is crucial for evaluating the damage to all potentially affected organs and determining the disease burden. This case report highlights the intricacies of GD type 1 by providing a thorough exploration of the clinical presentation and showcasing valuable insights into the unique manifestations of the disease. The key feature was his individual and family medical history, which allowed the identification and treatment of another case within the community.

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.

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.

The Complexities of Diagnosis with Co-Existing Gaucher Disease and Hemato-Oncology-A Case Report and Review of the Literature

Hematological abnormalities are the most common early symptoms of Gaucher disease (GD), with an increased risk of hematopoietic system malignancies reported in patients with GD. GD may be associated with monoclonal and polyclonal gammopathies; however, the mechanism of association of GD with multiple myeloma (MM) remains uncertain. Enzyme replacement therapy (ERT) has been shown to improve patients' cytopenia and it seems to facilitate anti-myeloma therapy in patients with co-occurring GD and MM. Although it is necessary to demonstrate the deficiency of enzymatic activity, as well as using genetic tests to finally diagnose GD, due to changes in the blood count image, bone marrow biopsy is still a frequent element of the GD diagnosis procedure. The diagnosis of GD is often delayed, mainly due to the heterogeneity of the histopathological picture of bone marrow biopsy or overlapping hematological abnormalities. Unrecognized and untreated GD worsens the response of a patient with an oncological disease to targeted treatment. We present a literature review, inspired by the case of a Caucasian patient initially diagnosed with MM and later confirmed with comorbid GD type 1 (GD1). We would like to point out the problem of underdiagnosis and delay in patients with GD.

The utilisation of primary health care system concepts positively impacts the assistance of patients with rare diseases despite limited knowledge and experience by health care professionals: A qualitative synopsis of the evidence including approximately 78 000 individuals

Background

Individuals with rare diseases (RD) have been historically understudied. Previous publications reported that existing primary health care (PHC) workforces and associated infrastructure had been shown to improve their access and health-related outcomes in low- and middle-income countries (LMICs). As current evidence about the impact of PHC on patients diagnosed with RD is yet highly dispersed, this scoping review aimed to collate available evidence of the impact of PHC on patients with RD and summarize published information from multiple stakeholders about the perceived usefulness and barriers to effective use of the PHC system.

Methods

We searched Embase, Health System Evidence, PubMed, LILACS / BVS, and The Cochrane Library, from inception to September 1, 2022, for publications providing clear expert- or experience-based insights or data from patients living with RD at the PHC level of care. We included publications highlighting barriers to integrated care of patients with RD, reported by multiple social actors involved in caring for patients with RD. Two investigators screened publications, extracted data, and clustered information among records deemed eligible for inclusion. Data synthesis was performed using narrative and thematic-based analysis. Major findings identified and coded through a semantic-driven analysis were processed in vosViewer software and reported using descriptive statistics.

Findings

Eighty publications were included in this review. Quali-quantitative analyses evidenced that the PHC level is essential for approaching patients with RD, mainly due to its longitudinal, multidisciplinary, and coordinated care delivery. In addition, several publications highlighted that the medical curriculum is inappropriate for preparing health care providers to deal with patients presenting unusual signs and symptoms and being diagnosed with RD. PHC teams are essential in orienting patients and families on emergency events. Technology-related concepts were reported in 19 publications, emphasizing their effectiveness on early diagnosis, optimal treatment definition, improvement of quality of life, and long-lasting follow-up.

Conclusions

We provided valuable information on the effectiveness of the PHC in fostering a creative, integrative, and supportive environment for patients living with RD. Our results can be helpful to several stakeholders in deciding what actions are still pending to achieve a solid and positive experience for patients with RD in the PHC.

Registration

PROSPERO (CRD42022332347).

Case report: Multidisciplinary collaboration in diagnosis and treatment of child gaucher disease

Gaucher disease (GD) is an inherited lysosomal storage disease caused by mutations in the glucocerebrosidase gene. The decrease of glucocerebrosidase activity in lysosomes results in the accumulation of its substrate glucocerebroside in the lysosomes of macrophages in organs such as the liver, spleen, bones, lungs, brain and eyes, and the formation of typical storage cells, namely "Gaucher cells", leading to lesions in the affected tissues and organs. Hepatosplenomegaly, bone pain, cytopenia, neurological symptoms, and other systemic manifestations are common in clinical practice. Most pediatric patients have severe symptoms. Early diagnosis and treatment are crucial to improve the curative effect and prognosis. However, due to the low incidence of this disease, multi-system involvement in patients, and diverse clinical manifestations, multidisciplinary teamwork is needed for comprehensive evaluation, diagnosis and treatment. In this study, we reported 2 cases of different types of GD who were diagnosed, treated and followed up by multidisciplinary collaboration in infancy.

[Misdiagnosis of Gaucher disease in real life: Retrospective study of the French Gaucher's disease registry]

INTRODUCTION

Gaucher disease is an autosomal recessive genetic disorder. It is caused by a deficiency of the lysosomal enzyme, glucocerebrosidase which leads to an accumulation of glucosylceramide in the macrophages. Splenomegaly, hepatomegaly, cytopenias (anemia, thrombocytopenia) and bone disorders are the main symptoms. The diagnosis is often delayed, leading to unnecessary investigations and treatments, and delaying the specific treatment. The primary objective of our study was to establish, in patients who had a diagnostic delay of more than one year, the reported misdiagnoses before the final diagnosis. The secondary objectives were to investigate the risk factors associated with error and delayed diagnosis.

METHODS

Retrospective study including patients with Gaucher disease from the French Gaucher Disease Registry. Collection of data by a single investigator from a standardized form.

RESULTS

Among 83 patients with a known diagnostic delay, 13 patients (15 %) had one or two misdiagnoses. These included osteo-articular diagnoses (osteomyelitis, osteoarthritis, arthritis, osteochondritis, rheumatic fever, n=8), haematological diagnoses (gestational thrombocytopenia, immunological thrombocytopenia, n=4), infectious diagnoses (visceral leishmaniasis, mononucleosis, n=2) and hemochromatosis. The osteo-articular and infectious diagnoses concerned the child and the adolescent while the haematological diagnoses and the hemochromatosis concerned the adult. No factors were found associated with misdiagnoses. Patients with a diagnostic delay greater than one year were less likely to have hepatosplenomegaly as the first symptom.

CONCLUSION

There is a risk of diagnostic error related to phenotypic heterogeneity and lack of specificity of Gaucher disease symptoms. This study helps to better identify the misdiagnoses associated with Gaucher disease.

Similarities and differences between Gaucher disease and acid sphingomyelinase deficiency: An algorithm to support the diagnosis

Lysosomal storage disorders are a group of inborn errors of metabolism due to defects in proteins crucial for lysosomal function. Gaucher disease is the most common autosomal recessive lysosomal storage disorder due to mutations in the GBA1 gene, resulting in the lysosomal deficiency of glucocerebrosidase activity. Gaucher disease is characterized by the toxic accumulation of glucosylceramide in the reticuloendothelial system. Acid sphingomyelinase deficiency (ASMD), previously known as Niemann Pick A/B disease, is also an autosomal recessive lysosomal storage disorder due to mutations in the SMPD1 gene, which result in acid sphingomyelinase deficiency and the accumulation of sphingomyelin in mononuclear phagocytic system and hepatocytes. The phenotypic expression of Gaucher disease type 1 (GD1), the most common type, and chronic visceral ASMD may overlap for several signs or symptoms. Splenomegaly is detectable in approximately 90% of the patients in both conditions; however, since GD1 is more frequent than ASMD, clinicians are more prone to suspect it, often neglecting the diagnosis of ASMD. Based on previous experience, a group of experts in the clinical and laboratory diagnosis, management, and treatment of lysosomal storage disorders developed an algorithm for both GD1 and ASMD to support physicians, including primary care providers, internists, and specialists (e.g., hepatologists, hematologists, and pulmonologists) to suspect and differentiate GD1 and ASMD and to provide the appropriate referral.

Global Incidence and Prevalence of Gaucher Disease: A Targeted Literature Review

Incidence and prevalence estimates for Gaucher disease (GD) are scarce for this rare disease and can be variable within the same region. This review provides a qualitative synthesis of global GD incidence and prevalence estimates, GD1-3 type-specific and overall, published in the last 10 years. A targeted literature search was conducted across multiple databases from January 2011 to September 2020, including web-based sources and congress proceedings to May 2021. Searches yielded 490 publications, with 31 analyzed: 20 cohort studies (15 prospective, 5 retrospective), 6 cross-sectional studies, 5 online reports (most from Europe (n = 11) or North America (n = 11); one multiregional). Across all GD types, incidence estimates ranged 0.45-25.0/100,000 live births (16 studies), lowest for Asia-Pacific. Incidence of GD1: 0.45-22.9/100,000 live births (Europe and North America) and GD3: 1.36/100,000 live births (Asia-Pacific only). GD type-specific prevalence estimates per 100,000 population were GD1: 0.26-0.63; GD2 and GD3: 0.02-0.08 (Europe only); estimates for GD type unspecified or overall ranged 0.11-139.0/100,000 inhabitants (17 studies), highest for North America. Generalizability was assessed as "adequate"or "intermediate" for all regions with data. GD incidence and prevalence estimates for the last 10 years varied considerably between regions and were poorly documented outside Europe and North America. Data for GD2 and GD3 were limited.

Screening for potential undiagnosed Gaucher disease patients: Utilisation of the Gaucher earlier diagnosis consensus point-scoring system (GED-C PSS) in conjunction with electronic health record data, tissue specimens, and small nucleotide polymorphism (SNP) genotype data available in Finnish biobanks

Background

Autosomal recessive Gaucher disease (GD) is likely underdiagnosed in many countries. Because the number of diagnosed GD patients in Finland is relatively low, and the true prevalence is currently not known, it was hypothesized that undiagnosed GD patients may exist in Finland. Our previous study demonstrated the applicability of Gaucher Earlier Diagnosis Consensus point-scoring system (GED-C PSS; Mehta et al., 2019) and Finnish biobank data and specimens in the automated point scoring of large populations. An indicative point-score range for Finnish GD patients was determined, but undiagnosed patients were not identified partly due to high number of high-score subjects in combination with a lack of suitable samples for diagnostics in the assessed biobank population. The current study extended the screening to another biobank and evaluated the feasibility of utilising the automated GED-C PSS in conjunction with small nucleotide polymorphism (SNP) chip genotype data from the FinnGen study of biobank sample donors in the identification of undiagnosed GD patients in Finland. Furthermore, the applicability of FFPE tissues and DNA restoration in the next-generation sequencing (NGS) of the GBA gene were tested.

Methods

Previously diagnosed Finnish GD patients eligible to the study, and up to 45,100 sample donors in Helsinki Biobank (HBB) were point scored. The GED-C point scoring, adjusted to local data, was automated, but also partly manually verified for GD patients. The SNP chip genotype data for rare GBA variants was visually assessed. FFPE tissues of GD patients were obtained from HBB and Biobank Borealis of Northern Finland (BB).

Results

Three previously diagnosed GD patients and one patient previously treated for GD-related features were included. A genetic diagnosis was confirmed for the patient treated for GD-related features. The GED-C point score of the GD patients was 12.5–22.5 in the current study. The score in eight Finnish GD patients of the previous and the current study is thus 6–22.5 points per patient. In the automated point scoring of the HBB subpopulation (N ≈ 45,100), the overall scores ranged from 0 to 17.5, with 0.77% (346/45,100) of the subjects having ≥10 points. The analysis of SNP chip genotype data was able to identify the diagnosed GD patients, but potential undiagnosed patients with the GED-C score and/or the GBA genotype indicative of GD were not discovered. Restoration of the FFPE tissue DNA improved the quality of the GBA NGS, and pathogenic GBA variants were confirmed in five out of six unrestored and in all four restored FFPE DNA samples.

Discussion

These findings imply that the prevalence of diagnosed patients (~1:325,000) may indeed correspond the true prevalence of GD in Finland. The SNP chip genotype data is a valuable tool that complements the screening with the GED-C PSS, especially if the genotyping pipeline is tuned for rare variants. These proof-of-concept biobank tools can be adapted to other rare genetic diseases.

Gaucher disease in North Macedonia: Unexpected prevalence of the N370S GBA1 allele with attenuated disease expression

The majority of Gaucher Disease (GD) cases result from pathologic mutations in the GBA1 gene. A rich mutational spectrum of about 500 identified variants has been recognized. The disease is characterized by phenotypic diversity. Data regarding the genotype-phenotype correlation are scanty and inconclusive. Here, we summarize the genetic and phenotypic “portraits” of 14 patients with GD type 1 in the Republic of North Macedonia, 4 of Macedonian and 10 of Albanian origin. Altogether, 6 variants were detected, compounding 6 different genotypes. All genotypes contained the N370S variant, which was detected with an overall prevalence of 60.7%. Other frequent variants included the 1263del55 deletion and the double mutant allele D409H;H255Q, each with a prevalence of 14.2%. We detected two rare mutations: W92* - a pathogenic nonsense mutation and D399N – a single nucleotide variant of uncertain pathogenicity. The most common genotypes were N370S/1263del55 and H255Q;D409H/N370S, both present in 4/14 patients, followed by N370S homozygosity (3/14). Splenomegaly was the most common clinical manifestation, identified in all patients. Hepatomegaly was less frequent and was present in 50% of cases. Thrombocytopenia was present in 9/14, while half of the patients had anemia. Bone pathology was demonstrated in 8 patients. Patients with different genotypes displayed a high degree of phenotypic heterogeneity, suggesting that the other allele determines the onset and severity of the disease in patients with the N370S mutation. Longer follow-up, bigger cohorts of patients and multicentric studies should be conducted to further define the association between the genotypic and phenotypic expression in GD.

Clinical Characteristics, Molecular Background, and Survival of Egyptian Patients With Gaucher Disease Over a 20-Year Follow-up

This study analyzes the general disease characteristics, impact of enzyme replacement therapy (ERT), and overall survival (OS) of 156 Egyptian patients with Gaucher disease (GD) enrolled on hormone replacement from 1998 to 2017. The mean age at diagnosis was 32.46±12.68 months. Anemia was noted at diagnosis in 50%, thrombocytopenia in 30.7%, severe splenomegaly in 58.7%, severe hepatomegaly in 11.9%, and skeletal findings were detected in 24.3% of the patients. The most prevalent GD type was type 3 (54.5%). Twenty-two of type 3 patients had no neurological manifestations at diagnosis, and 12 developed variable central nervous system manifestations during follow-up. The most common neurological features were limited eye movements, oculomotor apraxia, and squint. Of the 60 patients for whom genotypes were obtained, homozygous L444P was the most common (n=35/60, 58.3%). Treatment with ERT (imiglucerase) revealed significant improvements in blood indices, organ volumes, and growth parameters (P<0.05). Ten (11.7%) type 3 patients did not develop any neurological manifestations under ERT over 20 years. Mortality was 16%, and the 20-year OS was 73.3%. We conclude that in Egypt, type 3 is the most prevalent phenotype of GD, and homozygous L444P is the predominant GBA genotype of GD. Early age at diagnosis and treatment with ERT over 20 years revealed significant improvements in disease manifestations, with an OS of 73.3%.

A cross-sectional web-based survey among haematologists and gastroenterologists in Japan to identify the key factors for early diagnosis of Gaucher Disease

BACKGROUND

Gaucher Disease (GD) is a rare, inherited metabolic disorder resulting from glucocerebrosidase deficiency. Patients benefit from early treatment as complications can arise from delayed diagnosis.

AIMS

To measure GD awareness among Japanese haematologists and gastroenterologists, who are the specialists most likely to encounter patients with symptoms recognised in the Gaucher Earlier Diagnosis Consensus (GED-C), such as hepatosplenomegaly and thrombocytopenia. Additionally, we aimed to determine key signs from the GED-C associated with early diagnosis.

METHODS

A quantitative web survey assessed Japanese haematologists and gastroenterologists for their i) basic awareness of GD, ii) explicit awareness of GD signs, iii) explicit awareness of GD treatments, and iv) accuracy in suspecting GD in model patients.

RESULTS

Survey results from 160 haematologists and 166 gastroenterologists indicated that more than 50% of haematologists were aware of GD symptoms, diagnostic criteria and/or treatments, and 38% of them had experienced or suspected GD. The majority of gastroenterologists were unaware of GD or knew the disease only by name, with 20% experiencing or suspecting GD in practice. Almost 70% of haematologists knew of enzyme replacement therapy (ERT), while 47% of gastroenterologists were not aware of any treatments for GD. Of the GED-C items, an awareness of bone-associated signs was correlated with accurate GD diagnosis in model patients and this awareness was greater among haematologists than gastroenterologists.

CONCLUSIONS

Our study showed that haematologists had greater awareness of GD than gastroenterologists, and that bone pain may be a key sign of GD to enhance early diagnosis. This article is protected by copyright. All rights reserved.

The diagnosis and management of Gaucher disease in pediatric patients: Where do we go from here?

Gaucher disease (GD) is an autosomal recessive inherited lysosomal storage disease that often presents in early childhood and is associated with damage to multiple organ systems. Many challenges associated with GD diagnosis and management arise from the considerable heterogeneity of disease presentations and natural history. Phenotypic classification has traditionally been based on the absence (in type 1 GD) or presence (in types 2 and 3 GD) of neurological involvement of varying severity. However, patient management and prediction of prognosis may be best served by a dynamic, evolving definition of individual phenotype rather than by a rigid system of classification. Patients may experience considerable delays in diagnosis, which can potentially be reduced by effective screening programs; however, program implementation can involve ethical and practical challenges. Variation in the clinical course of GD and an uncertain prognosis also complicate decisions concerning treatment initiation, with differing stakeholder perspectives around efficacy and acceptable cost/benefit ratio. We review the challenges faced by physicians in the diagnosis and management of GD in pediatric patients. We also consider future directions and goals, including acceleration of accurate diagnosis, improvements in the understanding of disease heterogeneity (natural history, response to treatment, and prognosis), the need for new treatments to address unmet needs for all forms of GD, and refinement of the tools for monitoring disease progression and treatment efficacy, such as specific biomarkers.

Screening, patient identification, evaluation, and treatment in patients with Gaucher disease: Results from a Delphi consensus

Several guidelines are available for identification and management of patients with Gaucher disease, but the most recent guideline was published in 2013. Since then, there have been significant advances in newborn screening, phenotypic characterization, identification of biomarkers and their integration into clinical practice, and the development and approval of new treatment options. Accordingly, the goal of this Delphi consensus exercise was to extend prior initiatives of this type by addressing issues related to newborn screening, diagnostic evaluations, and treatment (both disease directed and adjunctive). The iterative Delphi process involved creation of an initial slate of statements, review by a steering committee, and three rounds of consensus development by an independent panel. A preliminary set of statements was developed by the supporting agency based on literature searches covering the period from 1965 to 2020. The Delphi process reduced an initial set of 185 statements to 65 for which there was unanimous support from the panel. The statements supported may ultimately provide a framework for more detailed treatment guidelines. In addition, the statements for which unanimous support could not be achieved help to identify evidence gaps that are targets for future research.

Novel Management and Screening Approaches for Haematological Complications of Gaucher's Disease

Purpose

Gaucher disease (GD) is the most common lysosomal storage disorder. The principal manifestations for its diagnosis and further monitoring include haematological manifestations such as anaemia, thrombocytopaenia, spleen enlargement, and bleeding disorders, among others. This review aims to summarise and update the role of haematological complications in GD diagnosis and follow-up, describe their management strategies, and to use these indicators as part of the diagnostic approach.

Materials and Methods

A systematic review following the recommendations of PRISMA-P 2020 was carried out. Publications indexed in the databases PubMed, Embase, Science Open, Mendeley, and Web of Science were electronically searched by three independent reviewers, and publications up to June 2021 were accessed. A total of 246 publications were initially listed, of which 129 were included for further review and analysis. Case reports were considered if they were representative of a relevant hematologic complication.

Results

From the first review dated in 1974 to the latest publication in 2021, including different populations confirmed that the haematological manifestations such as thrombocytopaenia and splenomegaly at diagnosis of GD type 1 are the most frequent features of the disease. The incorporation of haematological parameters to diagnosis strategies increases their cost-effectiveness. Hematologic parameters are part of the scoring system for disease assessment and the evaluation of therapeutic outcomes, providing reliable and accessible data to improve the management of GD. However, cytopaenia, underlying coagulation disorders, and platelet dysfunction need to be addressed, especially during pregnancy or surgery. Long-term haematological complications include the risk of neoplasia and immune impairment, an area of unmet need that is currently under research.

Conclusion

Haematological features are key for GD suspicion, diagnosis, and management. Normalization of hematological parameters is achieved with the treatment; however, there are unmet needs such as the underlying inflammatory status and the long-term risk of hematologic neoplasia.

Ambroxol chaperone therapy for Gaucher disease type I-associated liver cirrhosis and portal hypertension: a case report

BACKGROUND

Gaucher disease (GD) is a rare autosomal recessive inherited disease caused by the deficiency of glucocerebrosidase and characterized by a broad spectrum of clinical manifestations, including hepatosplenomegaly, bone infiltration, and cytopenia. Moreover, it is even involved in the central nervous system. GD is classified into three phenotypes on the ground of neurologic involvement: type 1 (GD1), the commonly adult-onset, non-neuropathic variant; type 2 (GD2), the acute neuropathic form; and type 3 (GD3), the severe chronic neuro-visceral form. Recently, several studies have shown a promising outcome of ambroxol chaperone therapy for the treatment of GD, but its therapeutic role in GD1-associated liver cirrhosis and portal hypertension was not verified.

CASE PRESENTATION

A 36-year-old male patient was admitted for esophageal varices lasting for one year with a 34-year history of liver and spleen enlargement. The patient was diagnosed with GD1 with cirrhosis and portal hypertension based on the identification of Gaucher cells and advanced fibrosis in the liver biopsy tissue and two known pathogenic mutations on the glucocerebrosidase (GBA) gene. The patient received 660 mg/d of ambroxol for up to two years. At his six-month follow-up, the patient exhibited a remarkable increase in GBA activity (+35.5%) and decrease in liver stiffness (-19.5%) and portal vein diameter (-41.2%) as examined by ultrasound elastography and computer tomography, respectively. At two-year follow-up, the liver stiffness was further reduced (-55.5%) in comparison with untreated patients.

CONCLUSION

This case report suggests that long-term treatment with high dose ambroxol may play a role in the reduction of hepatic fibrosis in GD1.

Economic burden and health related quality of life of ultra-rare Gaucher disease in China

Background

The diagnosis and health care of patients with rare diseases present a tremendous challenge worldwide. This study described the health care service utilization through participants’ perspective and estimated the cost of illness (COI), and patients with Gaucher disease (GD)’s/caregivers’ health-related quality of life in China.

Method

An online retrospective survey of patients with GD and their caregivers was conducted during May–June 2018. Socio-demographic, health service utilization, disease-related expenses, social support, sleep quality (Pittsburgh Sleep Quality Index [PSQI]), and the Short Form Health Survey (SF-36) were investigated. Using self-reported information, we estimated the annual COI, including direct healthcare, direct non-healthcare, and indirect costs.

Results

Forty patients and their 49 caregivers were surveyed. The patients’ onset age of GD was 9.3 ± 10.9; their disease course was 3.5 ± 3.1 years. 21 (42.9%) patients had ≥ 2 caregivers, but 35 (71.4%) caregivers reported have no experience as a caregiver. 79.6% caregivers have stopped working, and 87.8% changed weekly working schedule. Before final diagnosis, patients visited 3.9 ± 3.1 (max = 20) hospitals and took 1.2 ± 1.7 (max = 6.6) years for confirmed diagnosis. On average, 5.0 ± 9.6 misdiagnoses occurred, and the per-patient diagnoses cost was USD ($) 7576. After GD confirmation, 8 (16.3%) patients received no treatment, 40 (81.6%) received pharmacotherapy, 10 (20.4%) received surgery, 38 (77.6%) received outpatient service (8.8 ± 9.1 times/annually), and 37 (77.5%) received inpatient service (4.0 ± 3.5 times/annually). Annual per-patient COI was USD ($) 49,925 (95% confidence interval: 29,178, 70,672). Average direct healthcare cost was $41,816, including pharmaceutical ($29,908), inpatient ($7,451), and outpatient ($1,838). Productivity loss per-caregiver was $1,980, and their Zarit Burden Inventory score was moderate-severe (48.6 ± 19.6). Both patients/caregivers reported lower social support (32.4 ± 7.4, 34.9 ± 7.6), two times higher PSQI (7.9 ± 2.9, 8.7 ± 3.6), and half lower SF-36 (41.3 ± 18.6, 46.5 ± 19.3) than those reported for healthy Chinese individuals.

Conclusions

The high misdiagnosis rate, together with delayed diagnosis, substantial costs, and deteriorated health-related quality of life of GD patients as well as their heavy care burden, calls for extreme attention from policymakers in China. Further efforts of government and society are urgently demanded, including pharmaceutical reimbursement, screening newborns, developing precise diagnostic tools, and training doctors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-021-01963-6.

Fabry disease pain: patient and preclinical parallels

ABSTRACT

Severe neuropathic pain is a hallmark of Fabry disease, a genetic disorder caused by a deficiency in lysosomal α-galactosidase A. Pain experienced by these patients significantly impacts their quality of life and ability to perform everyday tasks. Patients with Fabry disease suffer from peripheral neuropathy, sensory abnormalities, acute pain crises, and lifelong ongoing pain. Although treatment of pain through medication and enzyme replacement therapy exists, pain persists in many of these patients. Some has been learned in the past decades regarding clinical manifestations of pain in Fabry disease and the pathological effects of α-galactosidase A insufficiency in neurons. Still, it is unclear how pain and sensory abnormalities arise in patients with Fabry disease and how these can be targeted with therapeutics. Our knowledge is limited in part due to the lack of adequate preclinical models to study the disease. This review will detail the types of pain, sensory abnormalities, influence of demographics on pain, and current strategies to treat pain experienced by patients with Fabry disease. In addition, we discuss the current knowledge of Fabry pain pathogenesis and which aspects of the disease preclinical models accurately recapitulate. Understanding the commonalities and divergences between humans and preclinical models can be used to further interrogate mechanisms causing the pain and sensory abnormalities as well as advance development of the next generation of therapeutics to treat pain in patients with Fabry disease.

Scoring system to facilitate diagnosis of Gaucher disease

Background

Gaucher disease (GD) manifests heterogeneously and other conditions are often misdiagnosed in its place, leading to diagnostic delays. The Gaucher Earlier Diagnosis Consensus (GED‐C) initiative proposed a point‐scoring system (PSS) based on the signs and covariables that are most indicative of GD to help clinicians identify which individuals to test for GD.

Aims

To validate the PSS retrospectively in a test population including patients with GD and other conditions with overlapping manifestations.

Methods

Four cohorts of adults with GD, liver disease, haematological malignancy or immune thrombocytopenia were identified from hospital records. Clinical data were audited for GED‐C factors identified as potentially indicative of GD and aggregate scores calculated (sum of scores/number of factors) based on published PSS weightings. Threshold discriminatory PSS scores, sensitivity and specificity were determined by receiver‐operating characteristic analysis.

Results

Among 100 patients (GD, n = 25; non‐GD, n = 75), analyses based on 11 possible factors estimated group mean (standard deviation) PSS scores of: GD (n = 14), 1.08 (0.25); non‐GD (n = 38), 0.58 (0.31). Mean between‐group difference (95% confidence interval) was −0.49 (−0.68, −0.31) and area under the receiver‐operating characteristic analysis curve (95% confidence interval) was 0.88 (0.78, 0.97). A threshold PSS score of 0.82 identified all 14 patients with GD in the analysis set (100% sensitivity) and 27 of 38 patients in the non‐GD group (71% specificity). Patients with liver disease and haematological malignancy were most likely to have manifestations overlapping GD.

Conclusions

Preliminary validation of the GED‐C PSS discriminated effectively between patients with GD and those with overlapping signs.

Hematological manifestations and complications of Gaucher disease

Introduction: Gaucher disease (GD), although pan-ethnic and rare (common in Ashkenazi Jews), is of great importance to hematologists both for diagnosis and management. The need for increased awareness of GD is that delayed diagnosis may lead to preventable irreversible complications (mainly skeletal) or unnecessary invasive procedures (e.g. bone marrow biopsy), and the birth of another affected sibling due to lack of genetic consulting.Areas covered: The review outlines the common hematological manifestations of GD, including splenomegaly, thrombocytopenia, and anemia. Other hematological manifestations such as coagulation abnormalities, platelet dysfunction, gammopathy, and other hematological malignancies associated with GD are also discussed. Current and future treatment modalities are delineated, including enzyme replacement and substrate reduction therapy, pharmacological chaperon, and gene therapy. A literature search was conducted to identify original research articles relevant to hematology manifestations and GD published before November 2020.Expert opinion: Patients with GD should be ideally followed and treated in a center of excellence where the GD expert benefits from experienced consultants in relevant disciplines. Due to the availability of several very expensive treatment options, it is important to have an unbiased expert who can select the most suitable management for the individual patients (including withholding prescription in asymptomatic patients).

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.

Pitfalls in the diagnosis of Gaucher disease in Iraq: A diagnostic experience from a developing country

Background and Objectives:

Gaucher disease (GD) is a rare hereditary disorder caused by deficiency of the lysosomal enzyme β-glucocerebrosidase. An early and definitive diagnosis minimizes the sequelae of misdiagnoses, and unnecessary and invasive diagnostic procedures.

Methods:

A cross-sectional descriptive study was conducted in the period from June to August, 2018, to analysing data of thirteen patients, retrospectively. They presented to the gastrointestinal and metabolic clinics in Children Welfare Teaching Hospital in Iraq, and had wrong and delayed diagnosis of GD.

Results:

Two groups of patients were identified, based on diagnosis by enzymatic assay (considering the test positive when the enzyme level is below the normal value); those who had false positive (low level of the enzyme) result and received enzyme replacement therapy for long time, and those who had false negative (normal level of the enzyme) results which caused delay in their diagnosis and treatment. Two main factors that misled the diagnosis were identified.

Conclusion:

Each patient with Gaucher disease need to be approached by taking a thorough history, a proper clinical examination, and then by being investigated, accordingly. Biomarkers and molecular genetic studies are more accurate and solid additional tools, to the enzymatic assays on dried blood sample (DBS).

Treatable lysosomal storage diseases in the advent of disease-specific therapy

Lysosomal storage diseases (LSD) comprise a rare and heterogeneous group of nearly 50 heritable metabolic disorders caused by mutations in proteins critical for cellular lysosomal function. Defects in the activity of these proteins in multiple organs leads to progressive intra-lysosomal accumulation of specific substrates, resulting in disruption of cellular functions, extracellular inflammatory responses, tissue damage and organ dysfunction. The classification and clinical presentation of different LSD are dependent on the type of accumulated substrate. Some clinical signs and symptoms are common across multiple LSD, while others are more specific to a particular syndrome. Due to the rarity and wide clinical diversity of LSD, identification and diagnosis can be challenging, and in many cases diagnosis is delayed for months or years. Treatments, such as enzyme replacement therapy, haemopoietic stem cell transplantation and substrate reduction therapy, are now available for some of the LSD. For maximum effect, therapy must be initiated prior to the occurrence of irreversible tissue damage, highlighting the importance of prompt diagnosis. Herein, we discuss the clinical presentation, diagnosis and treatment of four of the treatable LSD: Gaucher disease, Fabry disease, Pompe disease, and two of the mucopolysaccharidoses (I and II). For each disease, we present illustrative case studies to help increase awareness of their clinical presentation and possible treatment outcomes.

The Gaucher earlier diagnosis consensus point-scoring system (GED-C PSS): Evaluation of a prototype in Finnish Gaucher disease patients and feasibility of screening retrospective electronic health record data for the recognition of potential undiagnosed patients in Finland

Background

Gaucher disease (GD) is a rare inherited multiorgan disorder, yet a diagnosis can be significantly delayed due to a broad spectrum of symptoms and lack of disease awareness. Recently, the prototype of a GD point-scoring system (PSS) was established by the Gaucher Earlier Diagnosis Consensus (GED-C) initiative, and more recently, validated in Gaucher patients in UK. In our study, the original GED-C PSS was tested in Finnish GD patients. Furthermore, the feasibility of point scoring large electronic health record (EHR) data set by data mining to identify potential undiagnosed GD cases was evaluated.

Methods

This biobank study was conducted in collaboration with two Finnish biobanks. Five previously diagnosed Finnish GD patients and ~ 170,000 adult biobank subjects were included in the study. The original PSS was locally adjusted due to data availability issues and applied to the Finnish EHR data representing special health care recordings.

Results

All GD patients had high levels of the biomarker lyso-Gb1 and deleterious GBA mutations. One patient was a compound heterozygote with a novel variant, potentially pathogenic mutation. Finnish EHR data allowed the retrospective assessment of 27–30 of the 32 original GED-C signs/co-variables. Total point scores of GD patients were high but variable, 6–18.5 points per patient (based on the available data on 28–29 signs/co-variables per patient). All GD patients had been recorded with anaemia while only three patients had a record of splenomegaly. 0.72% of biobank subjects were assigned at least 6 points but none of these potential “GD suspects” had a point score as high as 18.5. Splenomegaly had been recorded for 0.25% of biobank subjects and was associated with variable point score distribution and co-occurring ICD-10 diagnoses.

Discussion

This study provides an indicative GED-C PSS score range for confirmed GD patients, also representing potential mild cases, and demonstrates the feasibility of scoring Finnish EHR data by data mining in order to screen for undiagnosed GD patients. Further prioritisation of the “GD suspects” with more developed algorithms and data-mining approaches is needed.

Funding

This study was funded by Shire (now part of Takeda).

Predicting the probability of Gaucher disease in subjects with splenomegaly and thrombocytopenia

Hematologists are frequently involved in the diagnostic pathway of Gaucher disease type 1 (GD1) patients since they present several hematological signs. However, GD1 is mainly underdiagnosed because of a lack of awareness. In this multicenter study, we combine the use of a diagnostic algorithm with a simple test (β-glucosidase activity on Dried Blood Spot) in order to facilitate the diagnosis in a population presenting to the hematologist with splenomegaly and/or thrombocytopenia associated with other hematological signs. In this high-risk population, the prevalence of GD1 is 3.3%. We propose an equation that predicts the probability of having GD1 according to three parameters that are routinely evaluated: platelet count, ferritin, and transferrin saturation.

The patient journey of patients with Fabry disease, Gaucher disease and Mucopolysaccharidosis type II: A German-wide telephone survey

Background

Lysosomal Storage Diseases (LSD) are rare and multisytemic diseases which are caused by lysosomal enzyme deficiencies leading into accumulation of waste products due to an interruption in the decomposition process. Due to the low prevalence and therefore limited disease awareness as well as the fact that LSD patients present with unspecific symptoms the final diagnosis is often made after a long delay. The aim of this German-wide survey was to characterize the period between onset of symptoms and final diagnosis regarding e.g. self-perceived health, symptom burden and false diagnoses for patients with selected LSDs (Fabry disease (FD), Gaucher disease (GD) and Mucopolysaccharidosis type II (MPS II).

Methods

The study was conducted as a telephone based cross-sectional survey. All patients living in Germany with a confirmed diagnosis of FD, GD or MPS II were eligible to participate. The questionnaire was provided in advance in order to enable the participants to prepare for the interview. Only descriptive analyses were carried out. Single analyses were not carried out for all three patient groups due low case numbers.

Results

Of the overall population, 39 patients have been diagnosed with FD, 19 with GD and 11 with MPS II with the majority of patients being index patients. The majority of FD patients reported their current health status as “satisfactory” or better (79.5%). Self-perceived health status was observed to be at least stable or improving for the majority of FD patients compared to the year prior to diagnosis. The most frequently reported symptoms for patients with FD were paraesthesias (51.3%), whereas patients with GD reported a tendency for bleeding, blue spots or coagulation disorder (63.2%) as well as hepatomegaly and/or splenomegaly (63.2%) as the most commonly appearing symptoms. The number of patients reporting misdiagnoses was n = 5 (13.5%) for patients with FD and n = 5 (27.8%) for patients with GD. The median duration of the diagnostic delay was 21.0 years for FD, 20.0 years for GD and 2.0 years for MPS II.

Conclusions

This study showed that self-perceived status of health for patients might improve once the final correct diagnoses has been made and specific treatment was available. Furthermore, it was observed that diagnostic delay is still high in Germany for a relevant proportion of affected patients. Further challenges in the future will still be to increase awareness for these diseases across the entire healthcare sector to minimize the diagnostic delay.

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.

Liver involvement in Gaucher disease: A practical review for the hepatologist and the gastroenterologist

Gaucher disease (GD), a rare lysosomal storage disorder caused by deficient glucocerebrosidase activity and consequent accumulation of glycosphingolipids in the mononuclear phagocyte system, may progress to disabling and potentially life-threatening complications when left undiagnosed and untreated. Unfortunately, because of non-specific signs and symptoms and lack of awareness, patients with type 1 GD, the most common non-neuropathic variant, frequently experience diagnostic delays. Since splenomegaly and thrombocytopenia are the dominant clinical features in many GD patients leading to first medical contact, the hepatologist and the gastroenterologist need to be aware of this condition. Liver involvement has been reported in the majority of GD patients, and comprises hepatomegaly, with or without liver enzymes alteration, fibrosis/cirrhosis, portal hypertension, focal liver lesions, and cholelithiasis. Moreover, GD is associated with several biochemical alterations of potential interest for the hepatologist and the gastroenterologist, including hypergammaglobulinemia, hyperferritinemia and metabolic abnormalities, that may lead to misdiagnoses with chronic liver diseases of common etiology, such as primary hemochromatosis, autoimmune liver diseases or nonalcoholic fatty liver disease. This comprehensive review, based on the collaborative experience of physicians managing patients with GD, provides practical information on the clinical, histological and radiological hepatic manifestations of GD aiming at facilitating the diagnosis of GD for the hepatologist and the gastroenterologist.

From the search for diagnosis to treatment uncertainties: challenges of care for rare genetic diseases in Brazil

Rare genetic diseases are an important public health problem, but they are still little studied in Collective Health. This article aims to analyze the 'therapeutic itineraries' of patients in search of a diagnosis and treatment for rare genetic diseases in the cities of Rio de Janeiro, Salvador and Porto Alegre. It focuses on the material challenges, emotional and structural problems faced in these trajectories. Semi-structured interviews were conducted with patients/caregivers and health professionals in the context of public health medical genetics. Our findings suggest that the experience of the rare genetic disease is aggravated by practical, inter-relational and bureaucratic/institutional problems. The reality of long and circuitous journeys to obtain a diagnosis, non-geneticists' lack of knowledge about rare diseases, difficulties in transportation and access to specialists, diagnostic and complementary examinations, and access to high-cost medicines and food supplies were common challenges in all the narratives examined in the three Brazilian cities. In addition, adherence to care provided by medical genetics requires action and strategies that depend on arrangements involving family members, physicians, patient associations, and the state.

[Diagnostic journey of type 1 Gaucher Disease patients: A survey including internists and hematologists]

INTRODUCTION

Gaucher disease (GD) is a rare genetic lysosomal storage disorder caused by a beta-glucocerebrosidase deficiency and responsible for a lysosomal storage disorder. GD is characterized by haematological, visceral and bone involvements. The aim of this study was to describe the diagnostic journey of type 1 GD patients as well as the role of the internist.

METHODS

A retrospective multicentric study involving type 1 GD patients has been conducted in 16 centers, between 2009 and 2011.

RESULTS

Fifty-five type 1 GD patients were included, under the care of an internist or an haematologist. They were originally hospitalized in 8 different specialized units. Diagnosis was established by bone-marrow aspiration in 22 patients (40%), by enzymatic assay of glucocerebrosidase activity in 15 patients (27%), and by bone-marrow biopsy in 9 patients (16%). The use of enzymatic assay became more frequent after 1990. The delay between first hospitalization due to GD symptoms and definitive diagnosis was less than one year for 38 patients. Patients with suspected GD were mainly referred to an internist physician.

CONCLUSION

GD seems to be better recognized and quickly diagnosed since 1990 in spite of the multiplicity of journeys. The role of the internist seems important.

Sex-Specific Patient Journeys in Early Parkinson's Disease in the Netherlands

Objective: To reconstruct a sex-specific patient journey for Dutch persons with Parkinson's disease (PD) during the first 5 years after diagnosis.

Method: We analyzed a national administrative medical claims database containing data of all patients newly diagnosed with PD between 2012 and 2016 in the Netherlands. We performed time-to-event analysis to identify the moments when patients received care from neurologists, allied healthcare therapists or general practitioners. We also extracted relevant clinical milestones: unexpected hospitalization for PD, pneumonia, orthopedic injuries, nursing home admission, and death. Using these data, we constructed the patient journey stratified for sex.

Results: We included claims data of 13,518 men and 8,775 women with newly diagnosed PD in the Netherlands. While we found little difference in neurologist consultations, women visited general practitioners and physiotherapists significantly earlier and more often (all p-values < 0.001). After 5 years, 37.9% (n = 3,326) of women had visited an occupational therapist and 18.5% (n = 1,623) a speech and language therapist at least once. This was 33.1% (n = 4,474) and 23.7% (n = 3,204) for men. Approximately 2 years after diagnosis, PD-related complications (pneumonia, orthopedic injuries, and PD-related hospitalization) occurred for the first time (women: 1.8 years; men: 2.3 years), and after 5 years, 72.9% (n = 6,397) of women, and 68.7% (n = 9,287) of men had experienced at least one.

Discussion: Considering the strengths and limitations of our methods, our findings suggest that women experience complications and access most healthcare services sooner after diagnosis and more frequently than men. The identified sex differences extend the debate about phenotypical differences in PD between men and women.

[Gaucher Disease type 1 mimicking immune thrombocytopenia: Role of hyperferritinemia and hypergammaglobulinemia in the initial evaluation of an isolated thrombopenia]

INTRODUCTION

Gaucher disease type 1 is a rare genetic disease. It can cause thrombocytopenia. Current guidelines do not support bone marrow examination in front of isolated thrombocytopenia if no evidence suggests malignant hemopathy. This strategy aiming at sparing unnecessary investigations makes such rare diseases more difficult to diagnose.

CASE REPORT

A 31-year-old woman was diagnosed with immune thrombocytopenia according to current guidelines. She presented later with mild splenomegaly. Bone marrow aspirate smears showed Gaucher cells. Gaucher disease was then confirmed. Looking backward, initial biological clues (hyperferritinemia, hypergammaglobulinemia) should have enabled to consider the diagnosis.

CONCLUSION

Gaucher disease type 1 can be responsible for apparently isolated thrombocytopenia. The disease must be looked for if the thrombocytopenia is associated with unexplained hypergammaglobulinemia or hyperferritinemia. Diagnosing immune thrombocytopenia without bone marrow sample requires to systematically pay attention to any clinical or biological abnormality, not to ignore rare differential diagnoses.

Three cases of multi-generational Gaucher disease and colon cancer from an Ashkenazi Jewish family: A lesson for cascade screening

Gaucher disease (GD) is one of the commonest lysosomal storage diseases that is inherited in an autosomal recessive manner and affects 1 in 50,000 to 100,000 people in the general population. The frequency is much higher (1 in 500 to 1000) in people of Ashkenazi Jewish heritage due to a founder effect. GD is caused by decreased or absent activity of β-glucosidase with subsequent accumulation of the substrate glucosylceramide in macrophages due to genetic alterations in the GBA gene. These often accumulate in the spleen, liver and bone marrow. Three types exist, with type 1 being the most common, also referred to as non-neuronopathic GD. A broad clinical spectrum exists; patients of any age may manifest with hepatosplenomegaly, anaemia, thrombocytopenia, lung disease, bone abnormalities or may remain asymptomatic throughout their lifespan. Multi-generational disease does not usually occur because the risk of disease with each pregnancy, presuming both parents are carriers of the condition, is 25%. Herein, we report an Ashkenazi Jewish family with multi-generational GD type 1 and multigenerational colon cancer in the same three individuals, and reinforce the importance of cascade screening in families with genetic conditions.

How we manage Gaucher Disease in the era of choices

Treatment of Gaucher Disease (GD) is now beset with the abundance of therapeutic options for an individual patient, making the choice of therapy complex for both expert and non-expert clinicians. The pathogenesis of all disease manifestations is a gene mutation-driven deficiency of glucocerebrosidase, but the clinical expression and response of each of the clinical manifestations to different therapies can be difficult to predict. Enzyme replacement therapy has been available since 1991 and is well-established, with known efficacy and minimal toxicity. Of interest, the three available enzymes are distinct molecules and were registered as new products, not biosimilars. Oral substrate reduction therapy has undergone a revitalisation with a newly approved agent in this class for which some efficacy and toxicity questions have been raised. Herein we present our approach to the management of GD in the era of choices, including a new algorithm for how to manage a newly diagnosed patient.

Recent advances in the diagnosis and management of Gaucher disease

INTRODUCTION

Gaucher disease, the autosomal recessive deficiency of the lysosomal enzyme glucocerebrosidase, is associated with wide phenotypic diversity including non-neuronopathic, acute neuronopathic, and chronic neuronopathic forms. Overlap between types can render definitive diagnoses difficult. However, differentiating between the different phenotypes is essential due to the vast differences in clinical outcomes and response to therapy. Genotypic information is helpful, but cannot always be used to make clinical predictions. Current treatments for Gaucher disease, including enzyme replacement therapy and substrate reduction therapy, can reverse many of the non-neurological manifestations, but these therapies must be administered continually and are extremely costly.

AREAS COVERED

We reviewed the literature concerning the varied clinical presentations of Gaucher disease throughout the lifetime, along with treatment options, management goals, and current and future research challenges. A PubMed literature search was performed for relevant publications between 1991 to January 2018.

EXPERT COMMENTARY

Interest and research in the field of Gaucher disease is rapidly expanding. However, significant barriers remain in our ability to predict phenotype, assess disease progression using objective biomarkers, and determine optimal treatment strategy on an individual basis. As the field grows, we anticipate identification of genetic modifiers, new biomarkers, and small-molecule chaperone therapies, which may improve patient quality of life.