Maja Djordjevic

Early achievement and maintenance of the therapeutic goals using velaglucerase alfa in type 1 Gaucher disease.

INTRODUCTION Therapeutic goals have been described to monitor achievement, maintenance and continuity of therapeutic response in patients with type 1 Gaucher disease receiving enzyme replacement therapy. AIM To benchmark the impact of velaglucerase alfa treatment against therapeutic goals for 5 key clinical parameters of type 1 Gaucher disease (anemia, thrombocytopenia, hepatomegaly, splenomegaly and skeletal pathology). METHODS In an open-label Phase I/II study, twelve adults with symptomatic type 1 Gaucher disease and intact spleens received velaglucerase alfa for 9 months (60 U/kg infusion every other week [EOW]). Eleven patients completed the study and 10 enrolled in a long-term extension. After 1 year, patients who achieved ≥ 2 hematological or organ goals began step-wise dose reduction from 60 to 45 then 30 U/kg EOW. Data for anemia, thrombocytopenia, hepatomegaly, splenomegaly and skeletal pathology at baseline and 4 years are available for 8 patients (3 male, 5 female). The proportion of patients at goal for anemia, thrombocytopenia, hepatomegaly and splenomegaly at baseline was compared with the proportion achieving each goal at 4 years. The proportion achieving the skeletal pathology goal was determined on the basis of Z-score improvement from baseline to 4 years. The proportion of patients who achieved all 5 goals at 4 years was compared with the proportion at goal for all 5 parameters at baseline. RESULTS At baseline, no patient was at goal for all clinical parameters. After 1 year of treatment, all patients maintained goals present at baseline, and all achieved ≥ 2 goals. All 8 patients began step-wise dose reduction from 60 to 30 U/kg EOW between 15 and 18 months. By year 4 of treatment, all patients met goals for all 5 clinical parameters; therefore 100% achievement was seen for each of the 5 long-term, therapeutic goals. DISCUSSION In this velaglucerase alfa Phase I/II and extension study, clinically meaningful achievement of each long-term, therapeutic goal was observed for each patient, despite dose reduction after 1 year. This is the first report of a cohort where all patients receiving ERT for type 1 Gaucher disease achieved all 5 of these long-term, therapeutic goals within 4 years of starting treatment and after ≥ 2years dose reduction.

Significant and continuous improvement in bone mineral density among type 1 Gaucher disease patients treated with velaglucerase alfa: 69-month experience, including dose reduction.

Since bone pathology is a major concern in type 1 Gaucher disease (GD1), we evaluated bone mineral density (BMD) in adults receiving velaglucerase alfa in the seminal Phase I/II and extension trial. Ten treatment-naïve symptomatic patients with GD1 (four men, six women; median age 35years, range 18-62years) were included; of these, four patients were receiving bisphosphonates at enrollment. Using WHO criteria to classify the lumbar spine (LS) and femoral neck (FN) BMD T-scores, respectively, one (10%) and four (40%) patients had osteoporosis; eight (80%) and five (50%) had osteopenia; and one each (10%) was in the normal range, at baseline. By Month 69, two LS and one FN osteopenic patients normalized and one FN osteoporotic patient became osteopenic; change was seen only in patients not receiving bisphosphonates. Significant improvements in BMD Z-scores were seen at the LS by Month 24 and at the FN by Month 33 and were continuous thereafter. In linear mixed models, Z-scores were significantly lower than the reference population at baseline and improved significantly with treatment (LS and FN both P<0.01); analysis of the subgroup of patients not receiving bisphosphonates showed similar results. In conclusion, in this small cohort, velaglucerase alfa was associated with clinically meaningful and statistically significant LS and FN BMD improvements as early as Month 24 (LS) and 33 (FN), despite dose reduction and significant baseline skeletal pathology. These results suggest that velaglucerase alfa may hold promise in the management of skeletal pathology associated with GD1.

Molecular and phenotypic characteristics of patients with phenylketonuria in Serbia and Montenegro

Phenylketonuria (PKU) is the most common inborn error of amino acid metabolism in Caucasians. PKU is caused by mutations in the gene encoding phenylalanine hydroxylase (PAH) enzyme. Here, we report the spectrum and the frequency of mutations in the PAH gene and discuss genotype–phenotype correlation in 34 unrelated patients with PKU from Serbia and Montenegro. Using both polymerase chain reaction–restriction fragment length polymorphism and ‘broad‐range’ denaturing‐gradient gel electrophoresis/DNA sequencing analysis, 19 disease‐causing mutations were identified, corresponding to mutation detection rate of 97%. The most frequent ones were L48S (21%), R408W (18%), P281L (9%), E390G (7%) and R261Q (6%), accounting for 60% of all mutant alleles. The genotype–phenotype correlation was studied in homozygous and functionally hemizygous patients. We found that the most frequent mutation, L48S, was exclusively associated with the classical (severe) PKU phenotype. The mutation E390G gave rise to mild PKU. For the mutation R261Q, patients had been recorded in two phenotype categories. Considering allele frequencies, PKU in Serbia and Montenegro is heterogeneous, reflecting numerous migrations over the Balkan Peninsula.

Etiology, clinical features and outcome of epilepsia partialis continua in cohort of 51 children

The objective of the study was to evaluate etiology, clinical characteristics and outcome in children with epilepsia partialis continua (EPC). The investigation included 51 children with EPC aged 0.2-18 years treated in the period 1993-2009. The median period from the onset of underlying disorder to EPC was 6 months (0-72 months). EPC was caused by different pathologies: inflammatory and immune-mediated (52%), metabolic (13.7%), structural brain abnormalities (11.8%), cryptogenic (7.8%), vascular (5.9%), dual (5.9%), postoperative (2%). Median duration of EPC was 15 days (1-200 days). EPC involved more frequently the right side of the body comparing to the left one. The outcome was assessed at the end of the follow up period (mean 6.5 years, ranged 0.2-16 years). Unchanged neurological status was observed in 10 (19.6%) children, neurological consequences in 33 (64.7%) children and lethal outcome in 8 (15.7%) children. The most frequent etiology in our cohort was inflammatory and immune-mediated disease of central nerve system including Rasmussens encephalitis. The duration of EPC was prolonged, most frequently involving the right upper limb. The outcome of EPC in children was unfavorable.

Newborn screening in southeastern Europe

The aim of our study was to assess the current state of newborn screening (NBS) in the region of southeastern Europe, as an example of a developing region, focusing also on future plans. Responses were obtained from 11 countries. Phenylketonuria screening was not introduced in four of 11 countries, while congenital hypothyroidism screening was not introduced in three of them; extended NBS programs were non-existent. The primary challenges were identified. Implementation of NBS to developing countries worldwide should be considered as a priority.

Phenylketonuria screening and management in southeastern Europe – survey results from 11 countries

BackgroundWe aimed to assess the current state of PKU screening and management in the region of southeastern Europe.MethodsA survey was performed involving all identified professionals responsible for the PKU management in the 11 countries from South-Eastern region of Europe (Albania, Bulgaria, Bosnia and Herzegovina, Croatia, Kosovo, Macedonia, Moldova, Montenegro, Romania, Serbia, Slovenia). The questionnaire was designed to assess the characteristics regarding PKU management in three main areas: nation-wide characteristics, PKU screening, and characteristics of the PKU management in the responding centre. It consisted of 56 questions. The distribution and collection of the questionnaires (via e-mail) was taking place from December 2013 to March 2014.ResultsResponses from participants from 11 countries were included; the countries cumulative population is approx. 52.5 mio. PKU screening was not yet introduced in 4 of 11 countries. Reported PKU incidences ranged from 1/7325 to 1/39338 (and were not known for 5 countries). National PKU guidelines existed in 5 of 11 countries and 7 of 11 countries had PKU registry (registries included 40 to 194 patients). The number of PKU centers in each country varied from 1 to 6. Routine genetic diagnostics was reported in 4 of 11 countries. Most commonly used laboratory method to assess phenylalanine levels was fluorometric. Tetrahydrobiopterine was used in only 2 of 11 countries. Most frequently, pediatricians were caring for the patients. Dietitian was a member of PKU team in only 4 of 11 countries, while regular psychological assessments were performed in 6 of 11 countries. Patient’s PKU society existed in 7 of 11 countries.ConclusionsThe region of southeastern Europe was facing certain important challenges of PKU screening and management. Neonatal PKU screening should be introduced throughout the region. Furthermore, PKU management was falling behind internationally established standards-of-care in many aspects.

Rasmussen syndrome and long-term response to thalidomide

We report a 13-year-old female who experienced symptoms and signs of Rasmussen encephalitis for the first time at the age of 5 years. Various therapeutic procedures, including conventional and new antiepileptic drugs, steroids, immunoglobulin, plasma exchanges, and partial hemispherectomy, were applied, but their results were unsatisfactory. During one of the exacerbations, when the patients life was endangered, thalidomide was administered. Frequency and intensity of epileptic seizures were reduced significantly, and the quality of her life improved. Except for moderate neutropenia, the other adverse effects were not recognized. In our opinion, thalidomide is not a first-choice drug for Rasmussen encephalitis but is a good alternative only for cases refractory to other well-known and accepted therapeutic procedures.

Gammopathy and B lymphocyte clonality in patients with Gaucher type I disease.

INTRODUCTION We evaluated a novel approach for investigation of lymphocyte dysregulation in Gaucher patients by including determination of IgH and TCR gene rearrangements together with levels of immunoglobulins, natural autoantibodies as well as presence of monoclonal protein. MATERIALS AND METHODS Measurement of serum immunoglobulins, monoclonal immunoglobulins, selected autoantibodies, as well as analysis of immunoglobulin heavy chain and T cell receptor gene rearrangements. RESULTS Immunoglobulin disorder was detected in 29.6% patients, 40.7% demonstrated presence of B cell clonality and 44.4% demonstrated presence of autoantibodies. In five patients in our series, the presence of IgH gene rearrangement was the only detectable indicator of B cell dysfunction. TCR gene rearrangements were not found in any of the patients. CONCLUSION Based on our results, we propose IgH gene rearrangements as a new biomarker for investigation of B cell dysfunction occurring as a complication of Gaucher disease.

Basal ganglia lesions in the early stage of Menkes disease

An 11-month-old boy presented with progressive truncal hypotonia with poor head control and myoclonic seizures. His hair was sparse and stiff, his skin hypopigmented. Magnetic resonance imaging (MRI) (Fig. 1) demonstrated slight volume loss of the supratentorial white matter, symmetrical T2-weighted (T2W) hyperintense signal of the putamens and isolated round lesions of the left caudate head. The basal ganglia lesions showed restricted diffusion on diffusion-weighted imaging (DWI) (Fig. 2). Light microscopy of the boy’s hair demonstrated pili torti. Low levels of plasma copper and caeruloplasmin confirmed the diagnosis of Menkes disease. Menkes disease is an X-linked recessive disorder of metal metabolism, due to a defect in intracellular– intercompartmental copper transport Bindu et al. (2007), Arita et al. (2009). Typical MRI findings are progressive degeneration of grey and white matter, followed by

Molecular and phenotypic characteristics of seven novel mutations causing branched-chain organic acidurias

Specific mitochondrial enzymatic deficiencies in the catabolism of branched‐chain amino acids cause methylmalonic aciduria (MMA), propionic acidemia (PA) and maple syrup urine disease (MSUD). Disease‐causing mutations were identified in nine unrelated branched‐chain organic acidurias (BCOA) patients. We detected eight previously described mutations: p.Asn219Tyr, p.Arg369His p.Val553Glyfs*17 in MUT, p.Thr198Serfs*6 in MMAA, p.Ile144_Leu181del in PCCB, p.Gly288Valfs*11, p.Tyr438Asn in BCKDHA and p.Ala137Val in BCKDHB gene. Interestingly, we identified seven novel genetic variants: p.Leu549Pro, p.Glu564*, p.Leu641Pro in MUT, p.Tyr206Cys in PCCB, p.His194Arg, p.Val298Met in BCKDHA and p.Glu286_Met290del in BCKDHB gene. In silico and/or eukaryotic expression studies confirmed pathogenic effect of all novel genetic variants. Aberrant enzymes p.Leu549Pro MUT, p.Leu641Pro MUT and p.Tyr206Cys PCCB did not show residual activity in activity assays. In addition, activity of MUT enzymes was not rescued in the presence of vitamin B12 precursor in vitro which was in accordance with non‐responsiveness or partial responsiveness of patients to vitamin B12 therapy. Our study brings the first molecular genetic data and detailed phenotypic characteristics for MMA, PA and MSUD patients for Serbia and the whole South‐Eastern European region. Therefore, our study contributes to the better understanding of molecular landscape of BCOA in Europe and to general knowledge on genotype–phenotype correlation for these rare diseases.