Consenso Argentino sobre Diagnóstico y Tratamiento de la Enfermedad de Niemann-Pick tipo C / Argentinean Consensus on the Diagnosis and Treatment of Niemann-Pick Disease type C

Resumen La enfermedad de Niemann-Pick tipo C (NPC) es un trastorno del metabolismo lisosomal que se debe a la presencia de variantes patogénicas bialélicas en los genes NPC1 o NPC2. El depósito intracelular de lípidos, especialmente colesterol no esterificado, provoca daño oxidativo en diversos tejidos, especialmente neuronas, bazo e hígado. Esto, a su vez, induce la aparición de un conjunto de síntomas neurológicos/psiquiátricos y viscerales, con una amplia variabilidad de edad de apa rición, desde formas prenatales/neonatales hasta otras de aparición en la vida adulta. En los últimos años ha habido avances considerables en la comprensión sobre esta enfermedad y su manejo. En el presente consenso un grupo de expertos argentinos abordan los enfoques actuales de diagnóstico, seguimiento y tratamiento de NPC, incluyendo el uso de miglustat como única terapia específica aprobada en la actualidad.

Abstract Niemann-Pick type C (NPC) is a disorder of the lyso somal metabolism due to biallelic pathogenic variants in NPC1 or NPC2. Intracellular deposit of lipids, mainly unesterified cholesterol, gives rise to oxidative damage in several tissues, mainly neurons, spleen and liver. This, in turn, is associated with a myriad of neurologi cal/psychiatric and visceral symptoms, with wide vari ability in age of presentation, from prenatal/neonatal to adult-onset forms of the disease. The last few years have seen considerable progress in understanding this disease and its management. In this consensus, current approaches to the diagnosis, follow-up and treatment of NPC (including the use of miglustat, the only specific drug approved at the time) are discussed by an Argentin ian panel of experts.

Advance in Niemann-Pick disease type C / 国际儿科学杂志

Niemann-Pick disease type C is a lipid storage disorder associated with impaired intracellular cholesterol trafficking, caused by mutations of either NPC1 or NPC2 genes.According to the age at onset of symptoms, it is divided into 5 categories, including neonatal, early-infantile, late-infantile, juvenile and adult type.There are differences in clinical manifestations and prognoses among each category.The characteristic clinical manifestations are hepatosplenomegaly, lung infiltration, vertical supranuclear gaze palsy and gelastic cataplexy.The definite diagnosis requires demonstration of unesterified cholesterol accumulated in fibroblasts cultured from skin biopsies with filipin staining and(or) of pathogenic mutation of NPC1/NPC2 genes.There is no effective treatment for this disease yet, therefore the overall prognosis is still poor.Miglustat can delay onset of the neurological symptoms, and prolong survival of partial patients.

Novel compound heterozygous mutation in NPC1 gene cause Niemann–Pick disease type C with juvenile onset

Niemann–Pick disease type C (NPC) is a progressive lysosomal storage disorder caused by mutations in the NPC1 (in 95% of cases) or NPC2 (in *5% of cases) genes, inherited in an autosomal recessive manner. We report the case of a 38-year-old woman with learning disorder from her first year of schooling, and could notice slow progressed cognitive impairment, social withdrawal, apathy, handwriting alterations, deterioration of language skills and dysphagia. Brain magnetic resonance imaging showed severe cerebellar atrophy, hypoplasia of the corpus callosum, asymmetric lateral ventricular enlargement, and severe enlargement of frontal and parietal subarachnoid spaces. Next generation sequencing for NPC genes (NPC1 and NPC2) detected compound heterozygous mutations in NPC1 gene, including c.1553G [A (p.Arg518Gln), paternally inherited, and c.1270C [ T (p.Pro424Ser) maternally inherited. The first mutation has been already described in literature and correlated to NPC, while the second mutation is still unknown. Moreover, filipin test and quantification of plasma oxysterols confirmed NPC diagnosis. We can suggest the missense mutation c.1270C [ T (p.Pro424Ser) as a new causative mutation of NPC

Enfermedad de Niemann-Pick en una escolar / Niemann-Pick Disease in a scholar girl

Introducción: La enfermedad de Niemann-Pick tipo C es una enfermedad poco frecuente, autosómica recesiva, caracterizada por el depósito de lípidos a nivel lisosomal, que, a pesar de ser tratable, es mortal en todos los casos y representa una importante carga para los pacientes y sus familias. Objetivo: Contribuir al conocimiento de esta rara enfermedad neurovisceral progresiva de curso fatal. Presentación del caso: Se trata de una niña de 7 años de edad, que a los 2 años asistió a consulta por trastornos de la marcha, con deterioro progresivo de esta, así como del lenguaje y el comienzo de crisis epilépticas. Evolutivamente presentó cataplejías gelásticas, paresia de la mirada vertical y esplenomegalia. Estos elementos clínicos evolutivos fueron lo suficientemente distintivos para orientar la sospecha clínica y las investigaciones necesarias para llegar al diagnóstico definitivo de la enfermedad. Con la confirmación de que se trataba de la enfermedad de Niemann-Pick tipo C, se comenzó tratamiento con miglustad a dosis de 100 mg dos veces al día. Conclusiones: El deterioro neurológico progresivo, la cataplejía gelástica, la paresia de la mirada vertical y la esplenomegalia, unido a los resultados del medulograma y el estudio genético permitieron el diagnóstico de esta entidad(AU)

Introduction: Niemann-Pick type C disease is a non-frequent, recessive autosomal one, which is characterized by lipids deposit in the lysosomal level. Although this disease is treatable, it is fatal in all the cases and it represents a important burden to patients and their families. Objective: To contribute to the knowledge on this rare, progressive neurovisceral disease with fatal evolution. Case presentation: Seven- years- old girl, whom at two years old attended to a consultation for walk disorders presenting a progressive worsening of it, as well of the speech, and also presented an onset of epileptic crisis. In the evolution she presented gelastic cataplexy, vertical look´s paresia and splenomegaly. These clinical evolutive elements were sufficiently distinctive to indicate the clinical suspicion and the necessary research to reach its definitive diagnostic. With the confirmation of Niemann-Pick type C disease, miglustad was used as treatment with a dose of 100 mg twice in the day. Conclusions: Progressive neurological worsening, gelastic cataplexy, vertical look´s paresia and splenomegaly joined with the results of a medulogram and the genetic study permitted this disease to be identified(AU)

Substrate reduction therapy in three patients with Gaucher disease

PURPOSE: Gaucher disease (GD) is the most common lysosomal storage disease caused by beta-glucocerebrosidase (GBA) deficiency. Oral substrate reduction therapy with miglustat (Zavesca®) was approved for the treatment of adults with GD type 1, for whom enzyme replacement therapy (ERT) is unsuitable or not a therapeutic option. In this study, we report the effect of miglustat (Zavesca®) in three Korean GD patients. MATERIALS AND METHODS: Clinical findings comprising age at diagnosis, presenting signs, laboratory findings at diagnosis, GBA activity and mutations, and clinical courses of the three patients were reviewed. RESULTS: Miglustat was administered to three patients who reported allergic reactions during intravenous imiglucerase infusions. One patient withdrew after 15 months of miglustat administration owing to continuous elevation of disease biomarker levels (chitotriosidase, acid phosphatase, and angiotensin-converting enzyme). Poor adherence to medication was suspected but was denied by the patient. In the other two patients, platelet count and levels of hemoglobin and other biomarkers remained stable during miglustat administration. However, they suffered from severe diarrhea and weight loss, which led to miglustat discontinuation after 1 and 12 months of administration. CONCLUSION: Our study shows that although miglustat is suggested to GD patients as an alternative treatment to ERT, significant adverse reactions may lead to discontinuation of miglustat. In addition, it is difficult to monitor the drug adherence.

Niemann-Pick disease type C: a case series of Brazilian patients / Doenca de Niemann-Pick tipo C: serie de casos de pacientes brasileiros

The aim of the study was to analyze a series of Brazilian patients with Niemann-Pick disease type C (NP-C). Method Correlations between clinical findings, laboratory data, molecular findings and treatment response are presented. Result The sample consisted of 5 patients aged 8 to 26 years. Vertical supranuclear gaze palsy, cerebellar ataxia, dementia, dystonia and dysarthria were present in all cases. Filipin staining showed the “classical” pattern in two patients and a “variant” pattern in three patients. Molecular analysis found mutations in the NPC1 gene in all alleles. Miglustat treatment was administered to 4 patients. Conclusion Although filipin staining should be used to confirm the diagnosis, bone marrow sea-blue histiocytes often help to diagnosis of NP-C. The p.P1007A mutation seems to be correlated with the “variant” pattern in filipin staining. Miglustat treatment response seems to be correlated with the age at disease onset and disability scale score at diagnosis. .

O objetivo desse estudo foi analisar uma série de casos de pacientes brasileiros com doença de Niemann-Pick tipo C (NP-C). Método Correlação entre manifestações clínicas, alterações laboratoriais, estudo molecular e resposta ao tratamento foram realizadas. Resultado A amostra consiste de 5 pacientes com idade entre 8 e 26 anos. Paralisia do olhar vertical supranuclear, ataxia cerebelar, demência, distonia e disartria estavam presentes em todos os casos. Coloração de filipina na cultura de fibroblastos mostrou padrão “clássico” em dois pacientes e padrão “variante” em três casos. O estudo molecular encontrou mutações no gene NPC1 em todos os alelos. O tratamento com miglustate foi realizado em 4 pacientes. Conclusão Embora coloração de filipina seja utilizada para confirmar o diagnóstico, o histiócito azul-marinho no aspirado de medula óssea frequentemente auxilia a confirmar o diagnóstico de NP-C. A mutação p.P1007A está correlacionada com o padrão “ variante” na coloração de filipina. A resposta ao tratamento com miglustate parece estar correlacionada com a idade e escore de desabilidade no momento do diagnóstico. .