Massive hepatic fibrosis in Gaucher's disease: clinico-pathological and radiological features

[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.

Natural history and management of liver dysfunction in lysosomal storage disorders

Lysosomal storage disorders (LSD) are a rare group of genetic disorders. The major LSDs that cause liver dysfunction are disorders of sphingolipid lipid storage [Gaucher disease (GD) and Niemann-Pick disease] and lysosomal acid lipase deficiency [cholesteryl ester storage disease and Wolman disease (WD)]. These diseases can cause significant liver problems ranging from asymptomatic hepatomegaly to cirrhosis and portal hypertension. Abnormal storage cells initiate hepatic fibrosis in sphingolipid disorders. Dyslipidemia causes micronodular cirrhosis in lipid storage disorders. These disorders must be keenly differentiated from other chronic liver diseases and non-alcoholic steatohepatitis that affect children and young adults. GD, Niemann-Pick type C, and WD also cause neonatal cholestasis and infantile liver failure. Genotype and liver phenotype correlation is variable in these conditions. Patients with LSD may survive up to 4-5 decades except for those with neonatal onset disease. The diagnosis of all LSD is based on enzymatic activity, tissue histology, and genetic testing. Enzyme replacement is possible in GD and Niemann-Pick types A and B though there are major limitations in the outcome. Those that progress invariably require liver transplantation with variable outcomes. The prognosis of Niemann-Pick type C and WD is universally poor. Enzyme replacement therapy has a promising role in cholesteryl ester storage disease. This review attempts to outline the natural history of these disorders from a hepatologist’s perspective to increase awareness and facilitate better management of these rare disorders.

In-depth phenotyping for clinical stratification of Gaucher disease

BACKGROUND

The Gaucher Investigative Therapy Evaluation is a national clinical cohort of 250 patients aged 5-87 years with Gaucher disease in the United Kingdom-an ultra-rare genetic disorder. To inform clinical decision-making and improve pathophysiological understanding, we characterized the course of Gaucher disease and explored the influence of costly innovative medication and other interventions. Retrospective and prospective clinical, laboratory and radiological information including molecular analysis of the GBA1 gene and comprising > 2500 variables were collected systematically into a relational database with banking of collated biological samples in a central bioresource. Data for deep phenotyping and life-quality evaluation, including skeletal, visceral, haematological and neurological manifestations were recorded for a median of 17.3 years; the skeletal and neurological manifestations are the main focus of this study.

RESULTS

At baseline, 223 of the 250 patients were classified as type 1 Gaucher disease. Skeletal manifestations occurred in most patients in the cohort (131 of 201 specifically reported bone pain). Symptomatic osteonecrosis and fragility fractures occurred respectively in 76 and 37 of all 250 patients and the first osseous events occurred significantly earlier in those with neuronopathic disease. Intensive phenotyping in a subgroup of 40 patients originally considered to have only systemic features, revealed neurological involvement in 18: two had Parkinson disease and 16 had clinical signs compatible with neuronopathic Gaucher disease-indicating a greater than expected prevalence of neurological features. Analysis of longitudinal real-world data enabled Gaucher disease to be stratified with respect to advanced therapies and splenectomy. Splenectomy was associated with an increased hazard of fragility fractures, in addition to osteonecrosis and orthopaedic surgery; there were marked gender differences in fracture risk over time since splenectomy. Skeletal disease was a heavy burden of illness, especially where access to specific therapy was delayed and in patients requiring orthopaedic surgery.

CONCLUSION

Gaucher disease has been explored using real-world data obtained in an era of therapeutic transformation. Introduction of advanced therapies and repeated longitudinal measures enabled this heterogeneous condition to be stratified into obvious clinical endotypes. The study reveals diverse and changing phenotypic manifestations with systemic, skeletal and neurological disease as inter-related sources of disability.

C5a Activates a Pro-Inflammatory Gene Expression Profile in Human Gaucher iPSC-Derived Macrophages

Gaucher disease (GD) is an autosomal recessive disorder caused by bi-allelic GBA1 mutations that reduce the activity of the lysosomal enzyme β-glucocerebrosidase (GCase). GCase catalyzes the conversion of glucosylceramide (GluCer), a ubiquitous glycosphingolipid, to glucose and ceramide. GCase deficiency causes the accumulation of GluCer and its metabolite glucosylsphingosine (GluSph) in a number of tissues and organs. In the immune system, GCase deficiency deregulates signal transduction events, resulting in an inflammatory environment. It is known that the complement system promotes inflammation, and complement inhibitors are currently being considered as a novel therapy for GD; however, the mechanism by which complement drives systemic macrophage-mediated inflammation remains incompletely understood. To help understand the mechanisms involved, we used human GD-induced pluripotent stem cell (iPSC)-derived macrophages. We found that GD macrophages exhibit exacerbated production of inflammatory cytokines via an innate immune response mediated by receptor 1 for complement component C5a (C5aR1). Quantitative RT-PCR and ELISA assays showed that in the presence of recombinant C5a (rC5a), GD macrophages secreted 8-10-fold higher levels of TNF-α compared to rC5a-stimulated control macrophages. PMX53, a C5aR1 blocker, reversed the enhanced GD macrophage TNF-α production, indicating that the observed effect was predominantly C5aR1-mediated. To further analyze the extent of changes induced by rC5a stimulation, we performed gene array analysis of the rC5a-treated macrophage transcriptomes. We found that rC5a-stimulated GD macrophages exhibit increased expression of genes involved in TNF-α inflammatory responses compared to rC5a-stimulated controls. Our results suggest that rC5a-induced inflammation in GD macrophages activates a unique immune response, supporting the potential use of inhibitors of the C5a-C5aR1 receptor axis to mitigate the chronic inflammatory abnormalities associated with GD.

Serum progranulin levels in paediatric patients with Gaucher disease; relation to disease severity and liver stiffness by transient elastography

BACKGROUND

Non-invasive screening for liver fibrosis using transient elastography (TE) could be of value in the management of Gaucher disease (GD). Progranulin (PGRN) is a novel disease modifier in GD and an independent marker of liver fibrosis.

OBJECTIVES

We determined PGRN levels in paediatric patients with GD and assessed its role as a potential marker for disease severity and relation to liver stiffness by TE.

METHODS

Fifty-one GD patients (20 had type 1 and 31 had type 3) with a median age of 9.5 years were compared to 40 age- and sex-matched healthy controls and were studied focusing on visceral manifestations, neurological disease, haematological profile and PGRN levels as well as abdominal ultrasound and TE. Patients were on enzyme replacement therapy (ERT) for various durations and those with viral hepatitis infection were excluded.

RESULTS

By TE, 14 GD patients (27.5%) had elevated liver stiffness ≥7.0 kPa. Liver stiffness was significantly higher in type 1 GD patients than type 3 (P = .002), in splenectomized patients (P = .012) and those with dysphagia (P < .001). Liver stiffness was positively correlated with age of onset of ERT (P < .001). PGRN levels were significantly lower in GD patients compared with controls (P < .001). PGRN was significantly lower in GD patients with squint (P = .025), dysphagia (P = .036) and elevated liver stiffness (P = .015). PGRN was positively correlated with white blood cell count (r = .455, P = .002) and haemoglobin (r = .546, P < .001), while negatively correlated with severity score index (r = -.529, P < .001), liver volume (r = -.298, P = .034) and liver stiffness (r = -.652, P < .001).

CONCLUSIONS

Serum PGRN levels were associated with clinical disease severity and elevated liver stiffness in paediatric GD patients.

Chitotriosidase: a marker and modulator of lung disease

Chitotriosidase (CHIT1) is a highly conserved and regulated chitinase secreted by activated macrophages; it is a member of the 18-glycosylase family (GH18). CHIT1 is the most prominent chitinase in humans, can cleave chitin and participates in the body's immune response and is associated with inflammation, infection, tissue damage and remodelling processes. Recently, CHIT1 has been reported to be involved in the molecular pathogenesis of pulmonary fibrosis, bronchial asthma, COPD and pulmonary infections, shedding new light on the role of these proteins in lung pathophysiology. The potential roles of CHIT1 in lung diseases are reviewed in this article.

This is the first review of chitotriosidase in lung diseasehttp://bit.ly/2LpZUQI

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.

AISF update on the diagnosis and management of adult-onset lysosomal storage diseases with hepatic involvement

Lysosomal storage diseases (LSDs) are a heterogeneous group of inherited disorders caused by loss-of-function mutations in genes encoding for lysosomal enzymes/proteins. The consequence is a progressive accumulation of substrates in these intracellular organelles, resulting in cellular and tissue damage. The overall incidence is about 1/8000 live births, but is likely underestimated. LSDs are chronic progressive multi-systemic disorders, generally presenting with visceromegaly, and involvement of the central nervous system, eyes, the skeleton, and the respiratory and cardiovascular systems. The age at onset and phenotypic expression are highly variable, according to the specific enzymatic defect and tissues involved, the residual activity, and the disease-causing genotype. Enzyme-replacement therapies and substrate-reduction therapies have recently become available, leading to the improvement in symptoms, disease progression and quality of life of affected individuals. Liver involvement and hepatosplenomegaly are frequent features of LSDs and a hallmark of adult-onset forms, frequently leading to medical attention. LSDs should therefore be considered in the differential diagnosis of liver disease with organomegaly. The present document will provide a short overview of adult-onset LSDs with hepatic involvement, highlighting the specificities and systemic manifestations of the ones most frequently encountered in clinical practice, which may hint at the correct diagnosis and the appropriate treatment.

Liver involvement in patients with Gaucher disease types I and III

Background & aims

Gaucher disease (GD) is a multisystemic disease. Liver involvement in GD is not well characterised and ranges from hepatomegaly to cirrhosis and hepatocellular carcinoma. We aim to describe, and assess the effect of treatment, on the hepatic phenotype of a cohort of patients with GD types I and II.

Methods

Retrospective study based on the review of the medical files of the Gaucher Reference Centre of the Hospital de Clínicas de Porto Alegre, Brazil. Data from all GD types I and III patients seen at the centre since 2003 were analysed. Variables were compared as pre- (“baseline”) and post-treatment (“follow-up”).

Results

Forty-two patients (types I: 39, III: 3; female: 22; median age: 35 y; enzyme replacement therapy: 37; substrate reduction therapy: 2; non-treated: 3; median time on treatment-MTT: 124 months) were included. Liver enzyme abnormalities, hepatomegaly, and steatosis at baseline were seen in 19/28 (68%), 28/42 (67%), and 3/38 patients (8%), respectively; at follow-up, 21/38 (55%), 15/38 (39%) and 15/38 (39%). MRI iron quantification showed overload in 7/8 patients (treated: 7; MTT: 55 months), being severe in 2/7 (treated: 2/2; MTT: 44.5 months). Eight patients had liver biopsy (treated: 6; MTT: 58 months), with fibrosis in 3 (treated: 1; time on treatment: 108 months) and steatohepatitis in 2 (treated: 2; time on treatment: 69 and 185 months). One patient developed hepatocellular carcinoma.

Conclusions

GD is a heterogeneous disease that causes different patterns of liver damage even during treatment. Although treatment improves the hepatocellular damage, it is associated with an increased rate of steatosis. This study highlights the importance of a follow-up of liver integrity in these patients.

Aberrant progranulin, YKL-40, cathepsin D and cathepsin S in Gaucher disease

In Gaucher disease, several macrophage-specific biomarkers have been validated for use in the clinic. However, Gaucher disease is more complex involving system-wide pathophysiology beyond the macrophage, and based on gene array analysis in our Gaucher disease mouse model and other emerging pathophysiologic insights, we evaluated serum levels of cathepsins D and S, YKL-40 and progranulin in Gaucher disease patients. We assessed their biomarker potential in Gaucher disease and compared them to established Gaucher disease biomarkers, chitotriosidase, chemokine ligand 18 (CCL18), and other indicators of disease severity and response to therapy. Mean YKL-40 and cathepsin D and S levels were significantly higher in Gaucher disease patients compared to healthy controls; in contrast, mean progranulin levels were lower in Gaucher disease patients compared to healthy controls. Enzyme replacement therapy resulted in a significant reversal of elevated cathepsin D and S but there was no change in progranulin and YKL-40 levels. Patients with persistent splenomegaly after long-term enzyme replacement therapy had significantly higher serum YKL-40 than patients with smaller spleens (63.0 ± 6.4 ng/ml vs. 46.4 ± 4.3 ng/ml, p = .03). Serum YKL-40 levels were higher in subjects with severe bone involvement (Hermann Score 3 to 5) compared to those with milder bone involvement (Hermann Score 1 to 2) (70.1 ± 4.3 ng/ml vs. 48.1 ± 3.7 ng/ml, p = .0002). YKL-40 was only weakly associated with chitotriosidase (r = 0.2, p = .008) and CCL18 (r = 0.3, p = .0004), and cathepsin S was moderately associated with chitotriosidase (r = 0.4, p = .01) and CCL18 (r = 0.6, p < .0001). Receiver operating curves for progranulin and YKL-40 demonstrated areas under the curves of 0.80 and 0.70, respectively. In conclusion, while these biomarkers do not meet robust properties of established macrophage-specific biomarkers, they may inform severity of skeletal disease, contribution of fibrosis to residual splenomegaly, and other disease manifestations. These findings, including markedly low progranulin levels that do not change upon enzyme replacement therapy, are intriguing to prompt further investigations to decipher their role in pathophysiology and relevance to diverse phenotypes of Gaucher disease.

Imaging of non-neuronopathic Gaucher disease: recent advances in quantitative imaging and comprehensive assessment of disease involvement

Gaucher disease is an inherited metabolic disorder resulting in deficiency of lysosomal enzyme β-glucocerebrosidase causing the accumulation of abnormal macrophages (“Gaucher cells”) within multiple organs, most conspicuously affecting the liver, spleen, and bone marrow. As the most common glycolipid metabolism disorder, it is important for radiologists encountering these patients to be familiar with advances in imaging of organ and bone marrow involvement and understand the role of imaging in clinical decision-making. The recent advent of commercially available, reliable, and reproducible quantitative MRI acquisitions to measure fat fractions prompts revisiting the role of quantitative assessment of bone marrow involvement. This manuscript reviews the diverse imaging manifestations of Gaucher disease and discusses more optimal quantitative approaches to ascertain solid organ and bone marrow involvement with an emphasis on future applications of other quantitative methods including elastography.

Reversal of life-threatening hepatopulmonary syndrome in Gaucher disease by imiglucerase enzyme replacement therapy

Advanced liver disease complicated by hepatopulmonary syndrome is a recognized complication of Gaucher disease. Macrophage-targeted, recombinant enzyme replacement therapy is effective in reversing clinical manifestations attributed to the accumulation of glycolipid-laden macrophages but it is not known whether advanced fibrotic features of the disease can be ameliorated. We describe a splenectomized patient with Gaucher disease who developed massive hepatomegaly, cirrhosis of the liver and life-threatening hepatopulmonary syndrome. Treatment with Imiglucerase enzyme replacement therapy resulted in dramatic reversal of hepatopulmonary syndrome and liver disease. Our report suggests that Gaucher disease pathology involving advanced fibrosis and life-threatening complications can be reversed by imiglucerase enzyme therapy.

Synopsis

Effect of imiglucerase enzyme replacement therapy on Hepatopulmonary Syndrome in Gaucher Disease.

Two siblings with Gaucher type 3c: different clinical presentations

Background Gaucher disease (GD) is a lysosomal storage disorder caused by autosomal recessive mutations in the glucocerebrosidase (GBA) gene, which encodes acid β-glucosidase. GD type 3c is a rare group characterised by cardiovascular involvement, and homozygous D448H is the most frequent mutation. Case presentation We describe two patients who had homozygous D448H mutations. The index patient had hepatosplenomegaly, liver insufficiency and cardiac involvement and her sister had severe cardiac involvement with cardiomyopathy and diffuse aortic calcification. The index case's liver was transplanted at the age of 6 months from a related donor and her sister who had severe cardiovascular disease died at the age of 12 years. Conclusions Our patients had clinical variability. We need to discuss whether liver involvement could be the initial signs in patients with GD type 3c.

Molecular Pathways and Respiratory Involvement in Lysosomal Storage Diseases

Lysosomal storage diseases (LSD) include a wide range of different disorders with variable degrees of respiratory system involvement. The purpose of this narrative review is to treat the different types of respiratory manifestations in LSD, with particular attention being paid to the main molecular pathways known so far to be involved in the pathogenesis of the disease. A literature search was conducted using the Medline/PubMed and EMBASE databases to identify studies, from 1968 through to November 2018, that investigated the respiratory manifestations and molecular pathways affected in LSD. Pulmonary involvement includes interstitial lung disease in Gaucher’s disease and Niemann-Pick disease, obstructive airway disease in Fabry disease and ventilatory disorders with chronic respiratory failure in Pompe disease due to diaphragmatic and abdominal wall muscle weakness. In mucopolysaccharidosis and mucolipidoses, respiratory symptoms usually manifest early in life and are secondary to anatomical malformations, particularly of the trachea and chest wall, and to accumulation of glycosaminoglycans in the upper and lower airways, causing, for example, obstructive sleep apnea syndrome. Although the molecular pathways involved vary, ranging from lipid to glycogen and glycosaminoglycans accumulation, some clinical manifestations and therapeutic approaches are common among diseases, suggesting that lysosomal storage and subsequent cellular toxicity are the common endpoints.

Hepatocellular carcinoma in Gaucher disease: an international case series

Gaucher disease (GD) is associated with an increased risk for malignancies. Next to hematological malignancies, the development of solid tumors in several organs has been described. The liver is one of the major storage sites involved in GD pathogenesis, and is also affected by liver-specific complications. In this case series, we describe 16 GD type 1 (GD1) patients from eight different referral centers around the world who developed hepatocellular carcinoma (HCC). Potential factors contributing to the increased HCC risk in GD patients are studied. Eleven patients had undergone a splenectomy in the past. Liver cirrhosis, one of the main risk factors for the development of HCC, was present in nine out of 14 patients for whom data was available. Three out of seven examined patients showed a transferrin saturation > 45%. In these three patients the presence of iron overload after histopathological examination of the liver was shown. Chronic hepatitis C infection was present in three of 14 examined cases. We summarized all findings and made a comparison to the literature. We recommend that GD patients, especially those with prior splenectomy or iron overload, be evaluated for signs of liver fibrosis and if found to be monitored for HCC development.

Prevalence and predictors of liver fibrosis evaluated by vibration controlled transient elastography in type 1 Gaucher disease

BACKGROUND & AIMS

Long-term liver-related complications of Gaucher disease (GD) include cirrhosis, portal hypertension and hepatocellular carcinoma. Although liver fibrosis is the main determinant of adverse liver-related clinical outcomes, it has rarely been evaluated in previously published cohorts of GD patients. We aimed at: assessing the prevalence of significant liver fibrosis in a cohort of patients with type 1 GD; identifying its predictors among GD-related variables, enzyme replacement therapy (ERT) and metabolic features.

METHODS

37 adult type 1 GD patients from two Italian academic referral centers were prospectively submitted to vibration controlled transient elastography (Fibroscan®); significant fibrosis was defined as liver stiffness ≥7 kPa.

RESULTS

Median liver stiffness was 4.6 [3-15.1] kPa and 7 patients (19%) had significant fibrosis. Significant fibrosis was associated with splenectomy (p = .046) and with scores (DS3: p = .002; SSI: p = .026) and biomarkers (ACE: p = .016; HDL cholesterol: p = .004) of GD severity. Length of ERT was significantly lower in GD patients with significant fibrosis. In the subgroup of 29 patients who were on stable ERT for at least 24 months, further to splenectomy, GD severity and non-N370S GBA1 genotypes, also diastolic blood pressure, BMI and the number of metabolic syndrome (MetS) components emerged as factors significantly associated with significant fibrosis.

CONCLUSIONS

Significant fibrosis is present in a remarkable proportion of adult type 1 GD patients. Splenectomy, GD severity and GBA1 genotypes are major GD-related predictors of liver fibrosis. Length of ERT is inversely correlated with liver disease in GD patients, suggesting a beneficial effect of ERT on liver fibrosis. However, GD patients on stable ERT should be monitored for metabolic complications, since MetS features may enhance liver disease progression despite optimal GD control.

Diagnosis and Management of Gaucher Disease in India – Consensus Guidelines of the Gaucher Disease Task Force of the Society for Indian Academy of Medical Genetics and the Indian Academy of Pediatrics

Justification

Gaucher disease (GD) is amongst the most frequently occurring lysosomal storage disorder in all ethnicities. The clinical manifestations and natural history of GD is highly heterogeneous with extreme geographic and ethnic variations. The literature on GD has paucity of information and optimal management guidelines for Indian patients.

Process

Gaucher Disease Task Force was formed under the auspices of the Society for Indian Academy of Medical Genetics. Invited experts from various specialties formulated guidelines for the management of patients with GD. A writing committee was formed and the draft guidelines were circulated by email to all members for comments and inputs. The guidelines were finalized in December 2016 at the annual meeting of the Indian Academy of Medical Genetics.

Objectives

These guidelines are intended to serve as a standard framework for treating physicians and the health care systems for optimal management of Gaucher disease in India and to define unique needs of this patient population.

Recommendations

Manifestations of GD are protean and a high index of suspicion is essential for timely diagnosis. Patients frequently experience diagnostic delays during which severe irreversible complications occur. Leucocyte acid β-glucosidase activity is mandatory for establishing the diagnosis of Gaucher disease; molecular testing can help identify patients at risk of neuronopathic disease. Enzyme replacement therapy for type 1 and type 3 Gaucher disease is the standard of care. Best outcomes are achieved by early initiation of therapy before onset of irreversible complications. However, in setting of progressive neurological symptoms such as seizures and or/neuroregression, ERT is not recommended, as it cannot cross the blood brain barrier. The recommendations herein are for diagnosis, for initiation of therapy, therapeutic goals, monitoring and follow up of patients. We highlight that prevention of recurrence of the disease through genetic counseling and prenatal diagnosis is essential in India, due to uniformly severe phenotypes encountered in our population.

Gaucher disease in the liver on hepatocyte specific contrast agent enhanced MR imaging

Gaucher disease is a hereditary lipid storage disorder that affects the enzyme beta glucocerebrosidase, causing accumulation of glucocerebroside in macrophages of the reticuloendothelial system. Accumulation can occur in the liver and spleen, manifesting as hepatosplenomegaly, as well as within the bone marrow. Hepatic involvement is usually diffuse but can occasionally manifest as focal liver lesions. We present a case of a 2-year-old boy with Gaucher disease and an infiltrating liver lesion detected on imaging, which was pathologically shown to be focal changes related to the disease. Imaging characteristics of this lesion using hepatocyte specific contrast agent enhanced MRI, which have not been previously discussed in the literature, are described.

The attenuated/late onset lysosomal storage disorders: Therapeutic goals and indications for enzyme replacement treatment in Gaucher and Fabry disease

Enzyme replacement therapies have been developed and authorized for commercial use for six different lysosomal storage disorders. For Gaucher disease, Fabry disease and mucopolysaccharidosis type 1, disease-specific treatments have been available for more than a decade. Although long term follow-up data are still sparse, therapeutic goals for patients with Gaucher disease and Fabry disease have been formulated and published for both adults and children. Without adaptation or modification, these goals are often applied in clinical research and in routine patient care across the entire phenotypic spectrum of disease, although in practice, patients commonly manifest high variability in clinical presentation and course of the illness. In this context, establishing goals for the follow-up and treatment of late onset/attenuated phenotypes is particularly challenging. In this chapter, we review current therapeutic goals for Gaucher disease and Fabry disease and discuss approaches for those with attenuated disease manifestations.

Clinical variability in neurohepatic syndrome due to combined mitochondrial DNA depletion and Gaucher disease

A 1-year-old girl born to consanguineous parents presented with unexplained liver failure, leading to transplantation at 19 months. Subsequent partial splenectomy for persistent cytopenia showed the presence of foamy cells, and Gaucher disease was confirmed by homozygosity for the p.Leu483Pro mutation in the GBA gene. She was treated by enzyme replacement therapy (ERT). Clinical follow-up showed mild developmental delay, strabismus, nystagmus and oculomotor apraxia. Biochemical studies revealed multiple respiratory chain deficiencies and a mosaic pattern of deficient complex IV immunostaining in liver and fibroblast. Molecular analysis identified a mtDNA depletion syndrome due to the homozygous p.Pro98Leu mutation in MPV17. A younger sister unaffected by mtDNA depletion, presented with pancytopenia and hepatosplenomegaly. ERT for Gaucher disease resulted in visceral normalization without any neurological symptom. A third sister, affected by both conditions, had marked developmental delay, strabismus and ophthalmoplegia but no liver cirrhosis. In conclusion, intrafamilal variability occurs in MPV17-related disease. The combined pathological effect of Gaucher and mitochondrial diseases can negatively impact neurological and liver functions and influence the outcome in consanguineous families. The immunocytochemical staining of OXPHOS protein in tissues and cultured cells is a powerful tool revealing mosaic pattern of deficiency pointing to mtDNA-related mitochondrial disorders.

Gaucher disease

Gaucher disease is the commonest lysosomal storage disease seen in India and worldwide. It should be considered in any child or adult with an unexplained splenohepatomegaly and cytopenia which are seen in the three types of Gaucher disease. Type 1 is the non-neuronopathic form and type 2 and 3 are the neuronopathic forms. Type 2 is a more severe neuronopathic form leading to mortality by 2 years of age. Definitive diagnosis is made by a blood test-the glucocerebrosidase assay. There is no role for histological examination of the bone marrow, liver or spleen for diagnosis of the disease. Molecular studies for mutations are useful for confirming diagnosis, screening family members and prognosticating the disease. A splenectomy should not be performed except for palliation or when there is no response to enzyme replacement treatment or no possibility of getting any definitive treatment. Splenectomy may worsen skeletal and lung manifestations in Gaucher disease. Enzyme replacement therapy (ERT) has completely revolutionized the prognosis and is now the standard of care for patients with this disease. Best results are seen in type 1 disease with good resolution of splenohepatomegaly, cytopenia and bone symptoms. Neurological symptoms in type 3 disease need supportive care. ERT is of no benefit in type 2 disease. Monitoring of patients on ERT involves evaluation of growth, blood counts, liver and spleen size and biomarkers such as chitotriosidase which reflect the disease burden. Therapy with ERT is very expensive and though patients in India have so far got the drug through a charitable access programme, there is a need for the government to facilitate access to treatment for this potentially curable disease. Bone marrow transplantation is an inferior option but may be considered when access to expensive ERT is not possible.

Loss of lysosomal membrane protein NCU-G1 in mice results in spontaneous liver fibrosis with accumulation of lipofuscin and iron in Kupffer cells

Human kidney predominant protein, NCU-G1, is a highly conserved protein with an unknown biological function. Initially described as a nuclear protein, it was later shown to be a bona fide lysosomal integral membrane protein. To gain insight into the physiological function of NCU-G1, mice with no detectable expression of this gene were created using a gene-trap strategy, and Ncu-g1^gt/gt mice were successfully characterized. Lysosomal disorders are mainly caused by lack of or malfunctioning of proteins in the endosomal-lysosomal pathway. The clinical symptoms vary, but often include liver dysfunction. Persistent liver damage activates fibrogenesis and, if unremedied, eventually leads to liver fibrosis/cirrhosis and death. We demonstrate that the disruption of Ncu-g1 results in spontaneous liver fibrosis in mice as the predominant phenotype. Evidence for an increased rate of hepatic cell death, oxidative stress and active fibrogenesis were detected in Ncu-g1^gt/gt liver. In addition to collagen deposition, microscopic examination of liver sections revealed accumulation of autofluorescent lipofuscin and iron in Ncu-g1^gt/gt Kupffer cells. Because only a few transgenic mouse models have been identified with chronic liver injury and spontaneous liver fibrosis development, we propose that the Ncu-g1^gt/gt mouse could be a valuable new tool in the development of novel treatments for the attenuation of fibrosis due to chronic liver damage.

Nonalcoholic Steatohepatitis: Diagnostic Challenges

This article reviews diagnostic criteria for nonalcoholic steatohepatitis (NASH), current grading and staging methodology, and diagnostic challenges and pitfalls in routine practice. Current practice guidelines and prognostic and treatment considerations are discussed. The clinical diagnosis of nonalcoholic fatty liver disease may represent stable disease without progressive liver damage, in the form of nonalcoholic fatty liver (NAFL), or aggressive disease that will progress to advanced fibrosis, in the form of NASH. NASH is diagnosed from a liver biopsy after assessment by a pathologist to distinguish NASH from NAFL (and other histologic mimics of NASH); this distinction is critical for patient management.

Liver fibrosis in type I Gaucher disease: magnetic resonance imaging, transient elastography and parameters of iron storage

Long term liver-related complications of type-1 Gaucher disease (GD), a lysosomal storage disorder, include fibrosis and an increased incidence of hepatocellular carcinoma. Splenectomy has been implicated as a risk factor for the development of liver pathology in GD. High ferritin concentrations are a feature of GD and iron storage in Gaucher cells has been described, but iron storage in the liver in relation to liver fibrosis has not been studied. Alternatively, iron storage in GD may be the result of iron supplementation therapy or regular blood transfusions in patients with severe cytopenia. In this pilot study, comprising 14 type-1 GD patients (7 splenectomized, 7 non-splenectomized) and 7 healthy controls, we demonstrate that liver stiffness values, measured by Transient Elastography and MR-Elastography, are significantly higher in splenectomized GD patients when compared with non-splenectomized GD patients (p = 0.03 and p = 0.01, respectively). Liver iron concentration was elevated (>60±30 µmol/g) in 4 GD patients of whom 3 were splenectomized. No relationship was found between liver stiffness and liver iron concentration. HFE gene mutations were more frequent in splenectomized (6/7) than in non-splenectomized (2/7) participants (p = 0.10). Liver disease appeared more advanced in splenectomized than in non-splenectomized patients. We hypothesize a relationship with excessive hepatic iron accumulation in splenectomized patients. We recommend that all splenectomized patients, especially those with evidence of substantial liver fibrosis undergo regular screening for HCC, according to current guidelines.

Mutations in GBA2 cause autosomal-recessive cerebellar ataxia with spasticity

Autosomal-recessive cerebellar ataxia (ARCA) comprises a large and heterogeneous group of neurodegenerative disorders with more than 20 different forms currently recognized, many of which are also associated with increased tone and some of which have limb spasticity. Gaucher disease is a lysosomal storage disease resulting from a defect in the enzyme acid β-glucosidase 1. β-glucosidase 2 is an enzyme with similar glucosylceramidase activity but to date has not been associated with a monogenic disorder. We studied four unrelated consanguineous families of Tunisian decent diagnosed with cerebellar ataxia of unknown origin. We performed homozygosity mapping and whole-exome sequencing in an attempt to identify the genetic origin of their disorder. We were able to identify mutations responsible for autosomal-recessive ataxia in these families within the gene encoding β-glucosidase 2, GBA2. Two nonsense mutations (c.363C>A [p.Tyr121(∗)] and c.1018C>T [p.Arg340(∗)]) and a substitution (c.2618G>A [p.Arg873His]) were identified, probably resulting in nonfunctional enzyme. This study suggests GBA2 mutations are a cause of recessive spastic ataxia and responsible for a form of glucosylceramide storage disease in humans.

Gaucher disease gene GBA functions in immune regulation

Inherited deficiency of acid β-glucosidase (GCase) due to biallelic mutations in the GBA (glucosidase, β, acid) gene causes the classic manifestations of Gaucher disease (GD) involving the viscera, the skeleton, and the lungs. Clinical observations point to immune defects in GD beyond the accumulation of activated macrophages engorged with lysosomal glucosylceramide. Here, we show a plethora of immune cell aberrations in mice in which the GBA gene is deleted conditionally in hematopoietic stem cells (HSCs). The thymus exhibited the earliest and most striking alterations reminiscent of impaired T-cell maturation, aberrant B-cell recruitment, enhanced antigen presentation, and impaired egress of mature thymocytes. These changes correlated strongly with disease severity. In contrast to the profound defects in the thymus, there were only limited cellular defects in peripheral lymphoid organs, mainly restricted to mice with severe disease. The cellular changes in GCase deficiency were accompanied by elevated T-helper (Th)1 and Th2 cytokines that also tracked with disease severity. Finally, the proliferation of GCase-deficient HSCs was inhibited significantly by both GL1 and Lyso-GL1, suggesting that the "supply" of early thymic progenitors from bone marrow may, in fact, be reduced in GBA deficiency. The results not only point to a fundamental role for GBA in immune regulation but also suggest that GBA mutations in GD may cause widespread immune dysregulation through the accumulation of substrates.

Imiglucerase in the treatment of Gaucher disease: a history and perspective

The scientific and therapeutic development of imiglucerase (Cerezyme(®)) by the Genzyme Corporation is a paradigm case for a critical examination of current trends in biotechnology. In this article the authors argue that contemporary interest in treatments for rare diseases by major pharmaceutical companies stems in large part from an exception among rarities: the astonishing commercial success of Cerezyme. The fortunes of the Genzyme Corporation, latterly acquired by global giant Sanofi SA, were founded on the evolution of a blockbuster therapy for a single but, as it turns out, propitious ultra-orphan disorder: Gaucher disease.

Management of portal hypertension in children

Portal hypertension can be caused by a wide variety of conditions. It frequently presents with bleeding from esophageal varices. The approach to acute variceal hemorrhage in children is a stepwise progression from least invasive to most invasive. Management of acute variceal bleeding is straightforward. But data on primary prophylaxis and long term management prevention of recurrent variceal bleeding in children is scarce, therefore prospective multicenter trials are needed to establish best practices.

Gaucher's disease

Gaucher's disease (GD) is the most common amongst the various disorders classified under the lysosomal storage disorders. GD is a model for applications of molecular medicine to clinical delineation, diagnosis, and treatment. The multiorgan and varied presentation of the disease makes it a challenge to diagnose GD early. The advent of enzyme replacement therapy in the early 1990s changed the management, and survival, of patients with GD. In addition to this, development of substrate reduction, pharmacological chaperone, and gene therapies has broadened the horizon for this rare disease. However, in resource-poor countries like ours, optimal management is still a distant dream.

Pulmonary vascular disease in Gaucher disease: clinical spectrum, determinants of phenotype and long-term outcomes of therapy

Pulmonary arterial hypertension (PAH) and hepatopulmonary syndrome (HPS) are rare pulmonary vascular complications of type 1 Gaucher disease (GD1). We examined GBA1 genotype, spleen status, Severity Score Index (SSI), and other patient characteristics as determinants of GD/PAH-HPS phenotype. We also examined the long-term outcomes of imiglucerase enzyme replacement therapy (ERT) +/- adjuvant therapies in 14 consecutive patients. We hypothesized a role of BMPR2 and ALK1 as genetic modifiers underlying GD/PAH-HPS phenotype. Median age at diagnosis of GD1 was 5 yrs (2-22); PAH was diagnosed at median 36 yrs (22-63). There was a preponderance of females (ratio 5:2). ERT was commenced at median 36.5 yrs (16-53) and adjuvant therapy at 36 yrs (24-57). GBA1 genotype was N370S homozygous in two patients, N370S heteroallelic in 12. Median SSI was 15 (7-20). All patients had undergone splenectomy at median age 12 yrs (2-30). In three patients, HPS was the initial presentation, and PAH developed after its resolution; in these three, HPS responded dramatically to ERT. In seven patients, sequencing of the coding regions of BMPR2 and ALK1 was undertaken: 3/7 were heterozygous for BMPR2 polymorphisms; none harbored ALK1 variants. With ERT (± adjuvant therapy), 5/14 improved dramatically, five remained stable, two worsened, and two died prematurely. In this largest series of GD/PAH-HPS patients, there is preponderance of females and N370S heteroallelic GBA1 genotype. Splenectomy appears essential to development of this phenotype. In some patients, HPS precedes PAH. BMPR2 and ALK1 appear not be modifier genes for this rare phenotype of GD. ERT +/- adjuvant therapy improves prognosis of this devastating GD phenotype.

Type 2 Gaucher disease: phenotypic variation and genotypic heterogeneity

Gaucher disease (GD), the most common lysosomal storage disease, results from a deficiency of the lysosomal enzyme glucocerebrosidase. GD has been classified into 3 types, of which type 2 (the acute neuronopathic form) is the most severe, presenting pre- or perinatally, or in the first few months of life. Traditionally, type 2 GD was considered to have the most uniform clinical phenotype when compared to other GD subtypes. However, case studies over time have demonstrated that type 2 GD, like types 1 and 3, manifests with a spectrum of phenotypes. This review includes case reports that illustrate the broad range of clinical presentations encountered in type 2 GD, as well as a discussion of associated manifestations, pathological findings, diagnostic techniques, and a review of current therapies. While type 2 GD is generally associated with severe mutations in the glucocerebrosidase gene, there is also significant genotypic heterogeneity.

Long-term outcomes of liver transplantation in type 1 Gaucher disease

Gaucher disease (GD) is the most prevalent lysosomal storage disorder. Enzyme replacement therapy (ERT) has demonstrable efficacy in reversing clinical and pathological manifestations of GD. We report four patients with GD and severe hepatic impairment who were successfully treated by orthotopic liver transplantation. Liver failure resulted from GD in two patients and due to a comorbidity in two others (HCV and autoimmune chronic active hepatitis). Following successful liver transplantation, patients received long-term ERT. Liver transplantation is a life-saving treatment for end-stage liver disease in patients with Gaucher disease. All four patients have had excellent outcomes from liver transplantation for up to 10 years postprocedure with no evidence of Gaucher-related pathology in the graft.

Gaucher disease: spectrum of sonographic findings in the liver

OBJECTIVE

Our large tertiary clinic for patients with Gaucher disease has used sonography as the preferred modality to monitor hepatosplenomegaly in hundreds of patients for more than 18 years. With the advent of specific enzyme replacement therapy (ERT), sonographic monitoring of changes in both hepatomegaly and the echogenicity of the hepatic tissue may highlight features that are amenable to ERT.

METHODS

All patients (500) seen at presentation and at annual or semiannual routine visits have undergone sonographic examinations by a single senior radiologist (I.H.-H.).

RESULTS

Thirty-nine patients (7.8%) had sonographic evidence of hepatic disease (21 male and 18 female; age range, 18-90 years); 26 (66.7%) of these received ERT, and 10 (25.6%) were splenectomized.

CONCLUSIONS

Liver findings are relatively rare. Among 500 patients, there was no instance of computed tomographic findings that had not been previously shown by sonography. Radiologists should be acquainted with the variable sonographic spectrum of the Gaucher liver. If hepatic lesions are small, hyperechoic, and slowly evolving, one may surmise that they are due to Gaucher cell accumulation. However, special attention should be paid to progressive deterioration and irregularities in liver texture because other metabolic processes and cancers must be ruled out.

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.

The female Gaucher patient: the impact of enzyme replacement therapy around key reproductive events (menstruation, pregnancy and menopause)

BACKGROUND

The principal manifestations of type 1 Gaucher disease (GD) (increased risk of bleeding, anaemia, splenomegaly, hepatomegaly and bone disease) are likely to affect females during reproductive events such as menarche and menstruation; fertility, pregnancy, parity, delivery and lactation; and menopause. In order to determine the optimal management of female Gaucher patients based on available data, we examine reproductive events and GD in untreated and alglucerase and/or imiglucerase-treated females.

METHODS

A panel of international clinicians experienced in the management of GD reviewed and presented evidence from peer-reviewed literature, a pharmacovigilance database on imiglucerase, and their own clinical experience to support discussions and recommendations. Nine panel members completed a 130-item-questionnaire on the outcomes of the management of female patients in their clinical practice. Results, covering menarche (137 females), menstruation (261 reports), fertility (295 females), pregnancy (416 pregnancies in 247 women) and menopause (45 women) were analysed. Data from a recent Canadian survey on 50 patients with 39 pregnancies, the imiglucerase pharmacovigilance database (100 pregnancies), and relevant literature (56 items covering 398 pregnancies in 205 women) were also reviewed.

KEY RESULTS

Menarche: May be delayed in girls with GD. Menorrhagia: Appears to be more common in GD than in the non-Gaucher population and may be ameliorated by alglucerase and/or imiglucerase treatment (menorrhagia in 67/133 (50.4%) untreated females compared with 37/128 (28.9%) treated; Mann-Whitney U test: p=0.001). Fertility: There is no evidence of decreased fertility in GD. Pregnancy: Pregnancy in GD may be complicated by haematological disease, organomegaly and bone involvement. GD diagnosis occurs frequently during pregnancy. Questionnaire results demonstrate: a reduced risk of spontaneous abortion in women treated with alglucerase and/or imiglucerase (untreated: 26/189 (13.8%); treated 1/58 (1.7%) chi(2)p=0.010); reduced risk of Gaucher-related complications during delivery (untreated 43/109 (39.4%); treated 3/46 (6.5%) chi(2)p<0.0005): and a reduced risk of Gaucher-related complications during the post partum period (untreated 15/71 (21.1%); treated 3/43 (7%) chi(2)p=0.014). There is no evidence to date of any untoward effect of alglucerase and/or imiglucerase on the fetus, or on infants breast fed by mothers receiving alglucerase and/or imiglucerase. Menopause: The impact of GD on menopause requires further study especially in relation to bone pathology.

CONCLUSIONS

On the basis of this review, GD may have an impact on reproductive events in affected women. Enzyme therapy may have benefits in reducing menorrhagia, spontaneous abortions and complications associated with delivery and the postpartum period.

Phenotypic continuum of type 2 Gaucher's disease: an intermediate phenotype between perinatal-lethal and classic type 2 Gaucher's disease

The natural history and clinical presentation of the perinatal-lethal Gaucher's disease, a severe variant of acute type 2 Gaucher's disease, is quite different from classic type 2 Gaucher's disease. Rare reported patients had an overlapping phenotype between these two forms confirming that phenotyping may be difficult. Here we report three patients with an intermediate phenotype. The first two patients showed at birth cholestatic jaundice, hepatosplenomegaly and hematological involvement consistent with hemophagocytosis in one patient, the death occurred from a severe liver involvement in one and lung disease in the second in the absence of neurological symptoms. The third patient displayed ichthyosis and facial dysmorphism but with neurological degeneration course and survival consistent with classic type 2 Gaucher's disease.

Life expectancy in Gaucher disease type 1

We estimated life expectancy at birth for Gaucher disease type 1 (GD1) patients by comparing survival data from GD1 patients enrolled in ICGG Gaucher Registry to the U.S. population using standard life table methods. 2,876 GD1 patients had 102 reported deaths in 13,509 person-years of follow-up. Estimated life expectancy at birth was 68 y, compared with 77 y in reference population; splenectomized patients, 64 y; nonsplenectomized, 72 y. Causes of death for 63/102 patients were malignancy (17/63), cardiovascular (11/63), and cerebrovascular (8/63). Estimated life expectancy at birth for GD1 patients was approximately 9 y less than reference population. Malignancies did not contribute to shortened life expectancy.

A benchmark analysis of the achievement of therapeutic goals for type 1 Gaucher disease patients treated with imiglucerase

To assess the extent to which patients with type 1 Gaucher disease (GD1) receiving individualized enzyme replacement therapy with imiglucerase attain six defined therapeutic goals. One hundred and ninety-five GD1 patients enrolled in the ICGG Gaucher Registry, all of whom had data available for hemoglobin, platelet count, liver volume, spleen volume, bone pain, and bone crises at first infusion and after 4 years of therapy with imiglucerase, were evaluated for achievement of published therapeutic goals. The proportion of patients who met all six therapeutic goals increased from 2.1% at first infusion to 41.5% at 4 years; > or =5 goals from 12.8% to 76.9%; > or =4 goals from 37.4% to 92.8%; > or =3 goals from 70.8% to 99.0%; and > or =2 goals from 95.4% to 99.5%. All patients met at least one goal at first infusion and after 4 years of treatment. The proportion of patients meeting specific therapeutic goals increased for all parameters between first infusion and 4 years of therapy: platelet count (24.6%-79.5%), spleen volume (25.6%-78.5%), liver volume (45.6%-90.8%), bone pain (62.6-70.3%), hemoglobin (68.2-91.8%), and bone crises (91.8-99.0%). On average, patients who received higher doses of imiglucerase achieved a greater number of therapeutic goals. This analysis provides a benchmark for evaluating the utility of a disease management approach for GD1 based on monitoring achievement of therapeutic goals after treatment with imiglucerase.

Gaucher disease: New developments in treatment and etiology

Gaucher disease (GD) is an autosomal recessive disease which if undiagnosed or diagnosed late results in devastating complications. Because of the heterozygous nature of GD, there is a wide spectrum of clinical presentation. Clinicians should be aware of this rare but potentially treatable disease in patients who present with unexplained organomegaly, anemia, massive splenomegaly, ascites and even cirrhosis of unknown origin. The treatment options for adult type GD include enzyme replacement treatment (ERT) and substrate reduction treatment (SRT) depending on the status of the patient. Future treatment options are gene therapy and “smart molecules” which provide specific cure and additional treatment options. In this review, we present the key issues about GD and new developments that gastroenterologists should be aware of.

Management of non-neuronopathic Gaucher disease with special reference to pregnancy, splenectomy, bisphosphonate therapy, use of biomarkers and bone disease monitoring

Enzyme replacement was introduced as treatment for non-neuronopathic Gaucher disease more than 15 years ago. To ensure the best use of this costly ultra-orphan agent, a systematic disease management approach has been proposed by an international panel; this includes the development, by consensus, of achievable treatment goals. Here we critically review these goals and monitoring guidelines and incorporate emerging experience of the disease in the therapeutic era, as well as contemporary clinical research. This review makes recommendations related specifically to the management of pregnancy; the appropriate use of splenectomy and bisphosphonate treatment; the relevance of biochemical markers to disease monitoring; and the use of semi-quantitative methods for assessing bone marrow infiltration. In addition, we identify key areas for development, including the requirement for a validated index of disease severity; the need to correlate widely used biomarkers with long-term disease outcomes, and the desirability of establishing agreed standards for monitoring of bone disease particularly in infants and children with Gaucher disease.

[Pathology along the liver sinusoids: intrasinusoidal findings]

Pathological findings in the liver sinusoids are mostly caused by extrahepatic or systemic diseases. Unclear fever, hepatosplenomegaly, portal hypertension or a mild elevation of liver enzymes are reasons for a liver biopsy leading to path-breaking diagnoses. Reactive intrasinusoidal lymphocytosis, especially with Epstein-Barr virus infections, has to be differentiated from predominantly intrasinusoidal lymphoproliferative malignancies. Intrasinusoidal megakaryocytes can be the first sign of a myeloproliferative or myelodestructive disease. Intrasinusoidal carcinosis and melanomatosis might present radiologically without tumor lesions and are easily overlooked histologically, in particular, if the critical cells have a similar size to hepatocytes. This also applies for intrasinusoidal storing macrophages. Gaucher's disease type I, and some other subtypes of inborn storage diseases might present for the first time in adulthood by hepatomegaly and Kupffer cell hypertrophy. Accompanying perisinusoidal fibrosis and immunohistochemical staining (CD68) can help to detect the large pale intrasinusoidal macrophages. In immunocompromized patients with fever, particular attention must be paid to intracellular agents, especially atypical mycobacteria and yeasts in non-granulomatous nested or dispersed Kupffer cells. Leishmaniasis with amastigotes in macrophages is accompanied by reactive sinusoidal plasmocytosis.

Oral maintenance clinical trial with miglustat for type I Gaucher disease: switch from or combination with intravenous enzyme replacement

Enzyme replacement therapy (ERT) with imiglucerase reduces hepatosplenomegaly and improves hematologic parameters in Gaucher disease type 1 within 6-24 months. Miglustat reduces organomegaly, improves hematologic parameters, and reverses bone marrow infiltration. This trial evaluates miglustat in patients clinically stable on ERT. Tolerability of miglustat and imiglucerase, alone and in combination, pharmacokinetic profile, organ reduction, and chitotriosidase activity were assessed. Thirty-six patients stable on imiglucerase were randomized into this phase II, open-label trial. Statistically significant changes from baseline were assessed (paired t test) on primary objectives with secondary analyses on biochemical and safety parameters. Liver and spleen volume were unchanged in switched patients. No significant differences were seen between groups regarding mean change in hemoglobin. Mean change in platelet counts was only significant between miglustat and imiglucerase groups (P = .035). Chitotriosidase activity remained stable. In trial extension, clinical endpoints were generally maintained. Miglustat was well tolerated alone or in combination. Miglustat's safety profile was consistent with previous trials; moreover, no new cases of peripheral neuropathy were observed. Gaucher disease type 1 (GD1) parameters were stable in most switched patients. Combination therapy did not show benefit. Findings suggest miglustat could be an effective maintenance therapy in stabilized patients with GD1.