Efficacy of Idursulfase therapy in patients with Mucopolysaccharidosis type II who initiated enzyme replacement therapy in adult age. A systematic review of the literature.

BACKGROUND: Enzyme replacement therapy (ERT) has been shown to decrease urine glycosaminoglycans (uGAGs) and liver and spleen volumes, and to improve clinical symptoms in mucopolysaccharidosis type II (MPS-II) patients. METHODS: A systematic search of the literature, from inception to August 2017, was conducted to identify randomized trials or observational studies including ≥1 MPS-II patients with ERT initiated in adult age (≥16 years) and evaluating ERT efficacy. Evidence was rated according to GRADE criteria. Common efficacy outcomes of the clinical studies were analyzed. Case reports were separately evaluated. RESULTS: One randomized clinical trial, 4 observational studies and 5 case reports were selected. ERT decreased uGAG levels and liver and spleen size with moderate evidence level and led to anti-ERT antibody and IRRS development in a significant proportion of patients with moderate evidence level. There were no conclusive results for beneficial effects on 6MWT, respiratory, cardiac and neurological function, joint mobility, sleep disorders of respiratory origin, and quality of life. LIMITATIONS: Excluding one observational study, all others were not conducted specifically in the target population (ERT ≥16 years). Data were from subgroup analyses of selected studies. There was a great heterogeneity between study designs and clinical outcomes evaluated. CONCLUSIONS: ERT improves uGAGs and liver/spleen volume with a moderate evidence level in MPS-II patients initiating therapy as adults, although the putative associated clinical benefit is unclear.

[Treatment of encephalopathy by means of valproic acid with carglumic acid. Reply]. / Tratamiento de la encefalopatia inducida por acido valproico con acido carbaglumico. Replica.

TITLE: Tratamiento de la encefalopatia inducida por acido valproico con acido carbaglumico. Replica.

[Treatment of encephalopathy by means of valproic acid with carglumic acid: two case reports and a review of the literature]. / Tratamiento de la encefalopatia por acido valproico con acido carbaglumico: descripcion de dos casos y revision de la bibliografia.

INTRODUCTION: Valproic acid (VPA) is a drug mainly used to treat epilepsy. Hyperammonaemic encephalopathy due to VPA is a rare but serious complication. The mechanism by which VPA influences the increase in ammonia consists in blocking the urea cycle, thereby inhibiting N-acetylglutamate synthase and diminishing acetyl coenzyme A. Generally, the treatment employed has been to withdraw VPA and to administer arginine, carnitine, antibiotics, glucose and protein restriction. Previous experience with carglumic acid is limited to reports of isolated cases of paediatric patients. CASE REPORTS: We report the cases of two adult patients with encephalopathy due to VPA who were treated with carglumic acid, in addition to the conventional measures. Following treatment with the drug, ammonia levels can be seen to return to normal values. In one of the two cases, owing to the existence of another cause of encephalopathy, no clinical improvement was observed. CONCLUSIONS: From the biochemical point of view, treating encephalopathy due to VPA with carglumic acid is a logical step, as it reverses the blockage of the urea cycle conditioned by VPA. The mechanism proposed as being the one by which brain toxicity and, therefore, encephalopathy are produced is the passage of ammonia in the form of glutamine to the inside of the cell, which then returns to ammonia and glutamate in the mitochondria and leads to oxidative stress. Carglumic acid must be considered an important part of the treatment in adult patients with hyperammonaemic encephalopathy due to VPA, although a randomised clinical trial needs to be conducted with the drug in order to test its efficacy.

TITLE: Tratamiento de la encefalopatia por acido valproico con acido carbaglumico: descripcion de dos casos y revision de la bibliografia.Introduccion. El acido valproico (VPA) es un farmaco principalmente usado en la epilepsia. La encefalopatia hiperamoniemica por VPA es una complicacion grave e infrecuente. El mecanismo por el que el VPA influye en la elevacion del amonio es bloqueando el ciclo de la urea, inhibiendo la N-acetilglutamato sintasa y disminuyendo la acetil coenzima A. De forma general, el tratamiento que se ha empleado ha sido la suspension del VPA y la administracion de arginina, carnitina, antibioticos, glucosa y restriccion proteica. La experiencia con acido carbaglumico se limita a comunicaciones de casos aislados de pacientes pediatricos. Casos clinicos. Descripcion de dos casos de pacientes adultos con encefalopatia por VPA tratados, ademas de las medidas convencionales, con acido carbaglumico. Tras el tratamiento con el farmaco se aprecia una normalizacion de los niveles de amonio. En uno de los casos, al existir otra causa de encefalopatia, no se aprecio mejora clinica. Conclusiones. Desde el punto de vista bioquimico es logico tratar la encefalopatia por VPA con acido carbaglumico, ya que revierte el bloqueo del ciclo de la urea condicionado por el VPA. El mecanismo propuesto por el que se produce la toxicidad cerebral y, por tanto, la encefalopatia, es el paso de amonio en forma de glutamina al interior celular, que retorna a amonio y glutamato en la mitocondria y genera estres oxidativo. El acido carbaglumico ha de considerarse como parte importante del tratamiento en pacientes adultos con encefalopatia hiperamoniemica por VPA, aunque es necesario realizar un ensayo clinico aleatorizado con el farmaco para comprobar su eficacia.

Clinical characteristics of adult patients with inborn errors of metabolism in Spain: A review of 500 cases from university hospitals.

Patients with inborn errors of metabolism (IEMs) have become an emerging and challenging group in the adult healthcare system whose needs should be known in order to implement appropriate policies and to adapt adult clinical departments. We aimed to analyze the clinical characteristics of adult patients with IEMs who attend the most important Spanish hospitals caring for these conditions. A cohort study was conducted in 500 patients, categorized by metabolic subtype according to pathophysiological classification. The most prevalent group of IEMs was amino acid disorders, with 108 (21.6%) patients diagnosed with phenylketonuria. Lysosomal storage disorders were the second group, in which 32 (6.4%) and 25 (5%) patients had Fabry disease and Gaucher disease respectively. The great clinical heterogeneity, the significant delay in diagnosis after symptom onset, the existence of some degree of physical dependence in a great number of patients, the need for a multidisciplinary and coordinated approach, and the lack of specific drug treatment are common features in this group of conditions.

Morbidity and mortality in the antiphospholipid syndrome during a 10-year period: a multicentre prospective study of 1000 patients.

OBJECTIVES: To assess the prevalence of the main causes of morbi-mortality in the antiphospholipid syndrome (APS) during a 10-year-follow-up period and to compare the frequency of early manifestations with those that appeared later. METHODS: In 1999, we started an observational study of 1000 APS patients from 13 European countries. All had medical histories documented when entered into the study and were followed prospectively during the ensuing 10 years. RESULTS: 53.1% of the patients had primary APS, 36.2% had APS associated with systemic lupus erythematosus and 10.7% APS associated with other diseases. Thrombotic events appeared in 166 (16.6%) patients during the first 5-year period and in 115 (14.4%) during the second 5-year period. The most common events were strokes, transient ischaemic attacks, deep vein thromboses and pulmonary embolism. 127 (15.5%) women became pregnant (188 pregnancies) and 72.9% of pregnancies succeeded in having one or more live births. The most common obstetric complication was early pregnancy loss (16.5% of the pregnancies). Intrauterine growth restriction (26.3% of the total live births) and prematurity (48.2%) were the most frequent fetal morbidities. 93 (9.3%) patients died and the most frequent causes of death were severe thrombosis (36.5%) and infections (26.9%). Nine (0.9%) cases of catastrophic APS occurred and 5 (55.6%) of them died. The survival probability at 10 years was 90.7%. CONCLUSIONS: Patients with APS still develop significant morbidity and mortality despite current treatment. It is imperative to increase the efforts in determining optimal prognostic markers and therapeutic measures to prevent these complications.