Haemostatic abnormalities in treatment-naïve patients with Type 1 Gaucher's disease

A Systematic Review and Meta-analyses of Longitudinal Studies on Drug Treatments for Gaucher Disease

OBJECTIVE

Gaucher disease (GD) is a rare disorder linked to the absence/deficiency of glucocerebrosidase. GD can be treated by enzyme replacement therapy (ERT) and substrate reduction therapy (SRT). The aim of this systematic review (SR) is to assess the effectiveness of drugs used for GD treatment.

DATA SOURCES

Searches were conducted in PubMed and Scopus, in April 2021. The search strategies encompassed the name of the disease and of the drug treatments. Manual search was also conducted.

STUDY SELECTION AND DATA EXTRACTION

Observational and interventional longitudinal studies evaluating ERT and SRT for GD were included. Single mean meta-analyses were conducted for each drug using R.

DATA SYNTHESIS

The initial search retrieved 2246 articles after duplicates were removed. Following screening and eligibility assessment, 68 reports were included. The studies evaluated imiglucerase, velaglucerase alfa, taliglucerase alfa, miglustat, and eliglustat. The results showed that ERT is effective as a treatment in both naïve and experienced patients. Miglustat did not significantly improve blood outcomes in naïve patients and resulted in a decrease in the platelet levels of experienced patients. Eliglustat was mainly assessed for experienced patients and resulted in stable outcome values.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This extensive SR confirms the effectiveness of GD treatments in short- and long-term follow-ups.

CONCLUSIONS

The results were favorable for all ERTs and for eliglustat. Based on the assessed evidence, miglustat did not achieved expressive results. However, all evidence should be interpreted considering its limitations and does not replace well-conducted randomized trials.

Hemostatic Abnormalities in Gaucher Disease: Mechanisms and Clinical Implications

Gaucher disease (GD) is a rare inherited lysosomal metabolism disorder, characterized by an accumulation into lysosomes of reticuloendothelial cells, especially in the bone marrow, spleen, and liver of β-glucosylceramide and glucosyl sphingosine, which is its deacylated product. Impaired storage is responsible for a chronic inflammatory state at the sites of accumulation and together represents the pathophysiological cause of GD. GD is a progressive, multi-organ chronic disorder. Type 1 GD is the most prevalent form, with heterogeneous multisystem involvement and different severity of symptoms at any age. Hematological involvement is consistent, and a bleeding tendency is frequent, particularly at diagnosis. Several coagulation and primary hemostasis abnormalities are observed in GD. Bleeding manifestations are rarely severe and usually mucocutaneous. Post-operative, delivery, and post-partum hemorrhages are also common. Thrombocytopenia, platelet function defects, and clotting abnormalities, alone or variably associated, contribute to increase the risk of bleeding in GD. Enzyme replacement therapy (ERT) or substrate reduction therapy (SRT) are the two specific available treatments effective in improving typical hematological symptoms and abnormalities, including those of hemostasis. However, the use of medication to potentiate hemostasis may be also useful in defined clinical situations: recent starting of ERT/SRT, surgery, delivery, and life-threatening bleeding.

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.

Platelet Activation and Reactivity in a Large Cohort of Patients with Gaucher Disease

OBJECTIVES

 Patients with Gaucher disease (GD) are at increased risk of bleeding and have varying degrees of thrombocytopenia, making the analysis of platelet function difficult. This study aimed to provide a clinically relevant quantitative assessment of platelet function and determine its relationship with bleeding and GD-related data.

METHODS

 Unstimulated and stimulated platelet function was measured by whole blood flow cytometry of platelet surface-activated αIIbβ3 integrin (detected with monoclonal antibody PAC1), P-selectin (CD62P), and lysosomal-associated membrane protein (LAMP3/CD63) in 149 GD patients.

RESULTS

 GD patients had a higher level of unstimulated CD63 expression than healthy subjects, which was mildly correlated with glucosylsphingosine (lyso-Gb1) levels (r = 0.17, p-value = 0.042). Splenectomized GD patients had a higher level of unstimulated αIIbβ3 integrin and P-selectin expression. Reduced platelet reactivity (-2 standard deviation of reference range) was found in 79 (53%, 95% confidence interval [CI]: 44-61%) patients, of whom 10 (6.7%, 95% CI: 3.3-12%) had more severe platelet dysfunction. In a multivariate model, only lyso-Gb1 levels were associated with the more severe platelet dysfunction. Fifty-four (49%) of 128 adult patients who completed the bleeding tendency questionnaire reported positive bleeding history. In a multivariate logistic model, older age (odds ratio [OR]: 1.05, 95% CI: 1.01-1.1) and low P-selectin reactivity (OR: 2.03, 95% CI: 1.25-3.35) were associated with more than one bleeding manifestation.

CONCLUSION

 Flow cytometry enables the study of platelet function in thrombocytopenic GD patients. A platelet degranulation defect, but not αIIbβ3 integrin activation defect, is associated with clinical bleeding. In vivo increased CD63 expression may be related to GD-related inflammation.

Coagulation Parameters in Adult Patients With Type-1 Gaucher Disease

Background

Gaucher disease is a rare inborn error of lysosomal metabolism, characterized by lysosomal storage of the β-glucosylceramide. Bleedings observed in type-1 Gaucher disease (GD1) are commonly attributed to a low platelet count, but they can also occur when the platelet count is normal or slightly low. Abnormal platelet function has been described and deficiencies in coagulation factors too, such as factors II, V, VII, VIII, IX, X, XI, XII, and von Willebrand factor. However, studies are few in number, involving few patients and having varying conclusions. The aim of this study was to analyze clotting factor deficiencies in a larger cohort of French patients with GD1.

Methods

This is an observational national study. The coagulation parameters were collected during routine GD1 monitoring and described retrospectively.

Results

We highlighted low levels of various coagulation factors in 46% of the patients with GD1. The most frequent coagulation abnormalities encountered were factor V, X, XI, and XII deficiencies. Deficits were usually mild and coagulation abnormalities tended to be more frequent in non-splenectomized patients.

Conclusions

In conclusion, frequent and varied coagulation abnormalities were found in a high proportion of GD1 patients.

Thromboelastography as a Surrogate Marker of Perisurgical Hemostasis in Gaucher Disease

Thromboelastography (TEG) has long been available for routine monitoring of perisurgical and postpartum hemostasis, especially at point of care. The purpose of this study is to retrospectively compare TEG parameters to concomitant standard clotting test results in an unselected cohort of patients with Gaucher disease to ascertain whether TEG values are specific and sensitive enough to substitute for classic coagulation tests for decision making. This remains a cogent concern because of high incidence of thrombocytopenia in patients with Gaucher disease. Thromboelastography values were compared to concomitant platelet counts, partial thromboplastin time, international normalization ratio, and plasma fibrinogen. Demographic characteristics were collected from patients’ files. There were 22 patients with Gaucher disease (2 children; 12.5%) for whom there were 24 TEG results at the same time as classic coagulation test results and 30% performed platelet function tests. The current study shows linear and/or monotonic relationships between platelet counts and several TEG values that were significant over a range of platelet counts including severe thrombocytopenia. The fibrinogen component, correlating only with the rate of clot lysis, played a lesser role. Based on these preliminary results albeit in a small cohort with only 1 case of hemorrhage, there is putative support for the intention to treat patients with Gaucher disease based on TEG results using the same TEG protocol as for other patients undergoing comparable procedures in our institution.

Hemorrhagic aspects of Gaucher disease

Gaucher disease (GD) is an inherited lysosomal disorder, originating from deficient activity of the lysosomal enzyme glucocerebrosidase (GCase). Normally, GCase hydrolyzes glucocerebroside (GC) to glucose and ceramide; however, impaired activity of this enzyme leads to the accumulation of GC in macrophages, termed "Gaucher cells." Gaucher disease is associated with hepatosplenomegaly, cytopenias, skeletal complications and in some forms involves the central nervous system. Coagulation abnormalities are common among GD patients due to impaired production and chronic consumption of coagulation factors. Bleeding phenomena are variable (as are other symptoms of GD) and include mucosal and surgical hemorrhages. FOUR MAIN ETIOLOGICAL FACTORS ACCOUNT FOR THE HEMOSTATIC DEFECT IN GD: thrombocytopenia, abnormal platelet function, reduced production of coagulation factors, and activation of fibrinolysis. Thrombocytopenia relates not only to hypersplenism and decreased megakaryopoiesis by the infiltrated bone marrow but also to immune thrombocytopenia. Autoimmunity, especially the induction of platelet antibody production, might cause persistent thrombocytopenia. Enzyme replacement therapy reverses only part of the impaired coagulation system in Gaucher disease. Other therapeutic and supportive measures should be considered to prevent and/or treat bleeding in GD. Gaucher patients should be evaluated routinely for coagulation abnormalities especially prior to surgery and dental and obstetric procedures.

Complex haemostatic abnormalities as a cause of bleeding after neurosurgery in a patient with Gaucher disease

We report a treatment-naïve patient with Gaucher disease (GD) who experienced repeated bleeding after three neurosurgeries for a brain tumour, identified as an oligoastrocytoma. The patient had normal values on basic haemostatic tests: prothrombin time, 75-105%; activated partial thromboplastin time, 30.3-34 s; and mild thrombocytopaenia, 96-115 × 10(9 )cells/l. However, additional tests showed mild von Willebrand factor (vWF) deficiency (vWF antigen, 56%; vWF ristocetin cofactor, 49%; factor VIII [FVIII], 54%) and abnormal collagen-mediated platelet aggregation (0.45-0.55). Bleeding control was achieved after vWF/FVIII concentrate and platelet transfusions. This case raises questions about the safe platelet count and basic haemostatic tests for assessing bleeding risk in patients with GD prior to surgery. In patients with GD, a minimum haemostatic evaluation should include platelet count and basic haemostatic tests such as fibrinogen, prothrombin time, activated partial thromboplastin time as well as platelet function tests and assessing vWF and FVIII levels. Specific coagulation factors or platelet function deficiencies should be corrected with factor concentrates or platelet transfusions.

Bone disease in patients with Gaucher disease

Gaucher disease is an inborn error of metabolism due to a deficiency of the lysosomal enzyme glucocerebrosidase. As a result of this deficiency, the substrate glucocerebroside accumulates in the liver, spleen, bone and bone marrow. Bone involvement can lead to abnormalities in bone growth, bone remodeling, bone infarcts, aseptic necrosis, osteonecrosis, increased fracture risk and lytic bone lesions. Patients may experience bone pain and bone crises related to bone infarcts. There is evidence of abnormal bone metabolism in both bone resorption and bone formation based upon biochemical abnormalities found in patients. In addition, both immunological and coagulation abnormalities have in part been implicated in the causation of bone disease. Treatment with enzyme replacement therapy and substrate reduction therapy has led to improvement in both the symptoms and the radiographic abnormalities seen in these patients. It is unknown whether these treatments lower fracture risk.