Fabry Disease in Slovakia: How the Situation Has Changed over 20 Years of Treatment.

Fabry disease (FD, OMIM#301500) is a rare inborn error of the lysosomal enzyme α-galactosidase (α-Gal A, EC 3.2.1.22) and results in progressive substrate accumulation in tissues with a wide range of clinical presentations. Despite the X-linked inheritance, heterozygous females may also be affected. Hemizygous males are usually affected more severely, with an earlier manifestation of the symptoms. Rising awareness among health care professionals and more accessible diagnostics have positioned FD among the most-common inherited metabolic diseases in adults. An early and correct diagnosis of FD is crucial with a focus on personalised therapy. Preventing irreversible destruction of vital organs is the main goal of modern medicine. The aim of this study was to offer a complex report mapping the situation surrounding FD patients in Slovakia. A total of 48 patients (21 males, 27 females) with FD are registered in the Centre for Inborn Errors of Metabolism in Bratislava, Slovakia. In our cohort, we have identified three novel pathogenic variants in five patients. Three patients presented with the frameshift mutation c.736delA, and two others presented with the missense mutations c.203T>C, c.157A>C. Moreover, we present a new clinical picture of the pathogenic variant c.801+1G>A, which was previously described and associated with the renal phenotype.

Atypical presentation of Charcot-Marie-Tooth disease type 1C with a new mutation: a case report.

BACKGROUND: Charcot-Marie-Tooth 1C (CMT1C) is a rare form of dominantly inherited CMT1 neuropathy caused by a mutated gene encoding lipopolysaccharide-induced tumour necrosis alpha factor (LITAF). CASE PRESENTATION: We report a 56-year-old patient with an atypical clinical phenotype of CMT1C, which started as progressive weakness of a single upper limb resembling acquired inflammatory neuropathy. Nerve conduction studies (NCS) and temporarily limited and partial effects of immunotherapy supported the diagnosis of inflammatory neuropathy. Significant progression of polyneuropathy, despite intensive long-lasting immunotherapy, together with repeatedly negative auxiliary investigations (CSF, MRI and antibodies) and genetic testing results finally led to the diagnosis of CMT1C neuropathy. CONCLUSIONS: CMT1C should be added to the list of inherited neuropathies that need to be considered in suspected cases of inflammatory demyelinating neuropathy.

New mutation of the ceruloplasmin gene in the case of a neurologically asymptomatic patient with microcytic anaemia, obesity and supposed Wilson's disease.

BACKGROUND: Aceruloplasminaemia is a very rare autosomal recessive disorder caused by a mutation in the ceruloplasmin gene, which is clinically manifested by damage to the nervous system and retinal degeneration. This classical clinical picture can be preceded by diabetes mellitus and microcytic anaemia, which are considered to be early manifestations of aceruloplasminaemia. CASE PRESENTATION: In our report, we describe the case of a patient with aceruloplasminaemia detected in an early stage (without clinical symptoms of damage to the nervous system) during the search for the cause of hepatopathy with very low values of serum ceruloplasmin. Molecular genetic examination of the CP gene for ceruloplasmin identified a new variant c.1664G > A (p.Gly555Glu) in the homozygous state, which has not been published in the literature or population frequency databases to date. Throughout the 21-month duration of chelatase treatment, the patient, who is 43 years old, continues to be without neurological and psychiatric symptomatology. We observed a decrease in the serum concentration of ferritin without a reduction in iron deposits in the brain on magnetic resonance imaging. CONCLUSION: Currently, there is no unequivocal recommendation of an effective treatment for aceruloplasminaemia. Early diagnosis is important in the neurologically asymptomatic stage.

Late Infantile Metachromatic Leukodystrophy Due to Novel Pathogenic Variants in the PSAP Gene.

Impairment of saposin B causes rare atypical metachromatic leukodystrophy (MLD). It is encoded (together with saposin A, C, and D) by the PSAP gene. Only ten pathogenic variants were described in the PSAP gene in MLD patients to date. We report on two novel variants in the PSAP gene - c.679_681delAAG in the saposin B encoding exon 6 and c.1268delT in the saposin D encoding exon 11 in a patient with MLD. We discuss the fact, that variants resulting in PSAP null allele can be shared in patients with the deficit of other saposins (A-D) or whole prosaposin. The patient's phenotype depends then on the nature of the second allele - atypical Gaucher disease in case of saposin A, MLD in case of saposin B, and Krabbe disease in case of saposin C impairing mutations. The clinically most severe prosaposin deficit is caused by the presence of two PSAP null alleles. Thus, the assessment of a variant impact is needed to prevent delayed diagnosis or misdiagnosis in patients with PSAP mutations.

Phelan-McDermid syndrome in adult patient with atypical bipolar psychosis repeatedly triggered by febrility.

Phelan-McDermid syndrome (PMD) is a rare genetic condition with only a few cases describing patients diagnosed as adults. We describe a long diagnostic odyssey of a 30-year-old woman who was diagnosed with Phelan-McDermid syndrom. Array comparative genomic hybridization analysis confirmed a 22q13.33 deletion, encompassing exon 9-23 of the SHANK3 gene and exon 1 of the ACR gene. We provide an uncommon feature of the disease, where psychotic alteration is repeatedly triggered by the same physical factor in our patient - mild fever episodes.

An unusually high frequency of SCAD deficiency caused by two pathogenic variants in the ACADS gene and its relationship to the ethnic structure in Slovakia.

BACKGROUND: Short-chain acyl-CoA dehydrogenase deficiency (SCADD) represents a rare autosomal recessive inborn metabolic disorder of mitochondrial ß-oxidation of monocarboxylic acids. Clinical symptoms can vary from a severe life-threatening condition to an asymptomatic state, reported in the majority of cases. Since the expansion of newborn screenings, more than three hundred probands were admitted for molecular-genetic analysis, most selected because of elevated values of C4-acylcarnitine detected in newborn screenings in Slovakia. Searching for the principal genomic changes led us to the selection of sixty-two patients in whom the presence of sequence variants in the ACADS gene was analysed and correlated with the available biochemical and clinical data. METHODS: Biochemical and molecular genetic tests were performed. Acylcarnitine profiles focused on an elevated level of C4-acylcarnitine, which was analysed via tandem mass spectrometry. Urinary organic acids, specifically a quantity of ethylmalonic acid, were determined by gas chromatography/mass spectrometry. The entire coding region of the ACADS gene was sequenced. A low-cost restriction fragment length polymorphism of PCR amplified fragments analysis (PCR-RFLP) of pathogenic variants was introduced and implemented for the molecular-genetic algorithm appropriate for the Slovak population. RESULTS: Our molecular genetic study was performed on sixty-two patients with a pathological biochemical pattern related to short-chain acyl-CoA dehydrogenase deficiency. In this cohort, we discovered a high occurrence of two rare pathogenic variants-the deletion c.310_312delGAG and the substitution c.1138C>T, with allelic frequencies of 64% and 31%, respectively. Up to 86% of investigated individuals belong to the Roma ethnic group. CONCLUSIONS: Analogous to other countries, SCADD is not included in the newborn screening programme. Based on the exceeded levels of the specific biomarker C4-acylcarnitine as well as ethylmalonic acid, we revealed a high prevalence of short-chain acyl-CoA dehydrogenase deficiency cases, confirmed by the findings of two rare pathogenic variants. A deletion c.310_312delGAG and c.1138C > T substitution in the ACADS gene appear with a high frequency in the Roma ethnic group of Slovakia. Due to the uncertainty of the pathogenicity and clinical consequences, it is important to follow up the morbidity and mortality in these patients over time and evaluate SCADD in relation to clinical outcomes and preventive healthcare recommendations.

The First Reported Case of Meckel-Gruber Syndrome Associated With Abnormal Karyotype Mosaic Trisomy 17.

Meckel-Gruber syndrome (MKS) is a rare lethal autosomal recessive disorder with typical anomalies including encephalocele, multicystic renal dysplasia, congenital liver fibrosis, and polydactyly. MKS is caused by mutations of genes localized on different chromosomes. Karyotypes of published Meckel-Gruber syndrome cases are without any aberrations. We present a male fetus with meningoencephalocele, multicystic renal dysplasia, congenital liver fibrosis, and other anomalies. Standard cytogenetic examination of cultured fetal skin and muscle fibroblasts showed mosaic trisomy 17. Homozygous deletion in CC2D2A gene was found by Sanger sequencing. This is to our knowledge the first case of genetically confirmed Meckel-Gruber syndrome with incidental cofinding of mosaic trisomy 17. Abnormal karyotype does not exclude diagnosis of MKS with risk of recurrence 25% in next pregnancy. In the case of anomalies typical for Meckel-Gruber syndrome, genetic analysis is indicated.

A novel mutation in the PEX12 gene causing a peroxisomal biogenesis disorder.

The peroxisomal biogenesis disorders are autosomal recessive diseases morphologically characterised by lacking peroxisomes, biochemically by generalised deficiency of peroxisomal constituent and clinically manifested by serious health problems. Genes involved in the peroxisomal biogenesis are defined as the PEX genes encoding proteins called the peroxins. These peroxins are required for function in assembly of the peroxisomal membrane or in import of the enzymes into the peroxisomes. In this study we present a full overview of the clinical presentation, biochemical and molecular data of patient with Zellweger syndrome from Slovakia. We investigated biochemical metabolites using gas chromatography/mass spectrometry. The presence of causal ins/del mutations we identified by a Sanger sequencing and RFLP. We reported that the patient was a compound heterozygote for mutations in the gene PEX12: a 2-bp insertion (c.767_768dupAT) and a 2-bp deletion (c.887_888delTC). The first one mentioned is a novel mutation, which has not been reported before. Both mutations create a frameshift of the open reading frame which result a premature STOP codon and generate a complete loss of the C-terminal RING finger domain that is crucial for the correct import of proteins into peroxisomes. We found causal mutations responsible for a severe phenotype, and moreover we noted a novel mutation c.767_768dupAT that has not been reported before. The presence of mutations was studied in all family members, and the resulting data were successfully utilized for prenatal diagnosis.