Endoscopic Approach in the Diagnosis of Gastrointestinal Acute Graft Versus Host Disease in Children.

The objectives of this study were to describe clinical, histological, and endoscopic findings in children undergoing gastrointestinal (GI) endoscopy for symptoms of digestive acute graft-versus-host disease (a-GvHD), to evaluate the rate of steroid-resistant GvHD and transplant-related mortality, and to describe the feasibility and safety of the endoscopic procedure. Methods: This was a retrospective study conducted, at the IRCSS Istituto G. Gaslini in Genova, Italy, in 26 children undergoing upper or lower GI endoscopy after allogeneic hematopoietic stem cell transplantation between 2000 and 2017. Results: Histology confirmed a diagnosis of a-GvHD in 73% of patients; it was frequently associated with steroid-resistant a-GvHD (P = 0.001) and with an increased transplant-related mortality. Additionally, one patient developed duodenal hematoma after endoscopy for a high-grade GI a-GvHD. Conclusions: In our experience, the endoscopic approach in the diagnosis of GI a-GvHD in children was feasible and safe. Furthermore, the histological diagnosis of GI a-GvHD was associated with an increased risk of steroid-resistant GvHD and with high transplant-related mortality.

Defective FAS-Mediated Apoptosis and Immune Dysregulation in Gaucher Disease.

BACKGROUND: Gaucher disease (GD) is a rare disorder characterized by defective function of ß-glucocerebrosidase, which leads to progressive accumulation of its substrate in various organs, particularly the mononuclear phagocyte system. Hepatosplenomegaly and cytopenia represent the disease's most common features, but patients with GD also show hyperinflammation, hypergammaglobulinemia, and immune dysregulation involving B, T, and natural killer cells. As clinical phenotype can be underhand, symptoms can overlap with autoimmune lymphoproliferative syndrome (ALPS) or other ALPS-like disorders. OBJECTIVE: To evaluate the ALPS-like immunological pattern and apoptosis function in patients with GD. METHODS: We evaluated lymphocyte subsets and immunophenotypic and serological features of ALPS (double-negative T cells [DNTs], B220+DNTs, CD27+, T-reg/HLA-DR ratio, IL-10, IL-18, vitamin B12) in a population of patients with GD. Moreover, we tested FAS/TRAIL-induced apoptosis and CASP8/CASP10/PARP function in patients showing an immune-dysregulation pattern. RESULTS: A total of 41 patients (33 treated, 8 treatment-naïve) were studied. Nine (21%) and 7 (17%) of 41 patients had high DNT and B220+DNT counts, respectively. Overall, 10 of 41(24%) patients showed immunological features suggestive of ALPS that were more frequent in treatment-naïve subjects (P = .040 vs P = .031) and in those with early onset of the disease (P = .046 vs P = .011), respectively. FAS-induced apoptosis and caspase activation were further evaluated in these 10 patients and were found to be defective in 7 of them. CONCLUSIONS: We show that patients with GD may have ALPS-like features and FAS-mediated apoptosis defects that are more pronounced in treatment-naïve subjects and in patients with early onset of the disease. Therefore, diagnostic workup of patients with an ALPS-like phenotype should include screening for GD.

Mucopolysaccharidoses: early diagnostic signs in infants and children.

Mucopolysaccharidoses (MPS) comprise a group of lysosomal disorders that are characterized by progressive, systemic clinical manifestations and a coarse phenotype. The different types, having clinical, biochemical, and genetic heterogeneity, share key clinical features in varying combinations, including joint and skeletal dysplasia, coarse facial features, corneal clouding, inguinal or abdominal hernias, recurrent upper respiratory tract infections, heart valve disease, carpal tunnel syndrome, and variable neurological involvement. In the severe forms, these features usually appear in the first months of life, but a correct diagnosis is often reached later when suggestive signs are manifest. All MPS types may have severe or attenuated presentations depending on the residual enzymatic activity of the patient. Based on data from the literature and from personal experience, here we underline the very early signs of the severe forms which should alert the paediatrician on their first appearance. A few early signs are typical of MPS (i.e. gibbus) while many are unspecific (hernias, upper airway infections, organomegaly, etc.), and finding the association of many unspecific signs might prompt the paediatrician to search for a common cause and to carefully look for other more specific signs (gibbus and other skeletal deformities, heart murmur). We stress the need to increase awareness of MPS among paediatricians and other specialists to shorten the still existing diagnostic delay. A timely diagnosis is mandatory for the commencement of treatment as soon as possible, when available, to possibly obtain better results.

Long term substrate reduction therapy with ezetimibe alone or associated with statins in three adult patients with lysosomal acid lipase deficiency.

BACKGROUND: Lysosomal acid lipase deficiency is an autosomal recessive metabolic disease with a wide range of severity from Wolman Disease to Cholesterol Ester Storage Disease. Recently enzyme replacement therapy with sebelipase alpha has been approved by drug agencies for treatment of this lysosomal disease. Ezetimibe is an azetidine derivative which blocks Niemann Pick C1-Like 1 Protein; as its consequence, plasmatic concentration of low density lipoproteins and other apoB-containing lipoproteins, that are the substrate of lysosomal acid lipase, are decreased. Furthermore, ezetimibe acts by blocking inflammasome activation which is the cause of liver fibrosis in steatohepatitis and in lysosomal storage diseases. RESULTS: Two patients with Cholesterol Ester Storage Disease were treated with ezetimibe for 9 years and a third patients for 10 years. Treatment was supplemented with low dose of atorvastatin in the first two patients during the last 6 years. All patients showed a significant reduction of alanine aminotransferase, cholesterol and triglyceride. Furthermore, no progression of liver fibrosis was demonstrated. CONCLUSION: In this observational case series, ezetimibe is effective, safe, and sustainable treatment for lysosomal acid lipase deficiency. Further studies are warranted to demonstrate that ezetimibe is an alternative therapy to enzyme replacement therapy.

The unusual association between Neuroblastoma and Gaucher Disease: Case report and review of the literature.

Gaucher disease (GD) patients have an increased risk of cancer, in particular of hematological origin, while the association between GD and Neuroblastoma (NBL) has never been described. Here we report the case of an adolescent diagnosed with NBL, also presenting splenomegaly and persistent thrombocytopenia. The association with GD, suggested by the histological findings on bone marrow biopsy, was confirmed by enzymatic and genetic tests. The possible pathogenetic mechanisms are briefly reviewed. The evidence of this new association supports the necessity of further studies on GD comorbidities and the need of systematic data collection and analysis, potentially through an international registry. A greater attention for GD in the hemato-oncological field is needed, in order to avoid underdiagnosis and to optimize treatment strategies.

Mutations in the Heme Exporter FLVCR1 Cause Sensory Neurodegeneration with Loss of Pain Perception.

Pain is necessary to alert us to actual or potential tissue damage. Specialized nerve cells in the body periphery, so called nociceptors, are fundamental to mediate pain perception and humans without pain perception are at permanent risk for injuries, burns and mutilations. Pain insensitivity can be caused by sensory neurodegeneration which is a hallmark of hereditary sensory and autonomic neuropathies (HSANs). Although mutations in several genes were previously associated with sensory neurodegeneration, the etiology of many cases remains unknown. Using next generation sequencing in patients with congenital loss of pain perception, we here identify bi-allelic mutations in the FLVCR1 (Feline Leukemia Virus subgroup C Receptor 1) gene, which encodes a broadly expressed heme exporter. Different FLVCR1 isoforms control the size of the cytosolic heme pool required to sustain metabolic activity of different cell types. Mutations in FLVCR1 have previously been linked to vision impairment and posterior column ataxia in humans, but not to HSAN. Using fibroblasts and lymphoblastoid cell lines from patients with sensory neurodegeneration, we here show that the FLVCR1-mutations reduce heme export activity, enhance oxidative stress and increase sensitivity to programmed cell death. Our data link heme metabolism to sensory neuron maintenance and suggest that intracellular heme overload causes early-onset degeneration of pain-sensing neurons in humans.

Long-term outcome of a successful cord blood stem cell transplant in mevalonate kinase deficiency.

Mevalonate kinase deficiency (MKD) is a rare autosomal recessive inborn error of metabolism with an autoinflammatory phenotype that may be expressed as a spectrum of disease phenotypes, from those with prevailing autoinflammatory syndrome and variable response to anti-inflammatory therapies, to mevalonic aciduria, which is associated with dysmorphic features, severe neurologic involvement, and the worst prognosis. We describe a boy, aged 2 years, 10 months, with severe phenotype of mevalonate kinase deficiency who underwent allogeneic hematopoietic stem cell transplantation (HSCT) from HLA-identical unrelated cord blood because his condition had failed to improve with antiinflammatory treatment as first-line therapy and an anticytokine drug as second-line therapy. The child had a sustained remission of febrile attacks and inflammation after transplant, and during a 5-year follow-up period, psychomotor and neurologic development were normal, without signs of underlying disease or late transplant-related effects. This case confirms that allogeneic HSCT is a safe and effective cure for patients affected by MKD in whom anticytokine drugs alone are insufficient for the management of autoinflammatory syndrome and for the unfavorable outcome of the disease.