Recommendations for pre-symptomatic genetic testing for hereditary transthyretin amyloidosis in the era of effective therapy: a multicenter Italian consensus.

Hereditary transthyretin amyloidosis (ATTRv, v for variant) is a late-onset, autosomal dominant disease caused by progressive extracellular deposition of transthyretin amyloid fibrils, leading to organ damage and death. For other late-onset fatal diseases, as Huntington's disease, protocols for pre-symptomatic genetic testing (PST) are available since decades. For ATTRv, limited experience has been reported to date, mostly gathered before the availability of approved therapies. We aimed at developing recommendations for a safe and feasible PST protocol in ATTRv in the era of emerging treatments, taking also into account Italian patients' characteristics and healthcare system rules. After an initial survey on ongoing approaches to PST for ATTRv in Italy, two roundtable meetings were attended by 24 experts from 16 Italian centers involved in the diagnosis and care of this disease. Minimal requirements for PST offer and potential critical issues were highlighted. By November 2019, 457 families affected by ATTRv with 209 molecularly confirmed pre-symptomatic carriers were counted. The median age at PST was 41.3 years of age, regardless of the specific mutation. Half of the Italian centers had a multidisciplinary team, including a neurologist, an internist, a cardiologist, a medical geneticist and a psychologist, although in most cases not all the specialists were available in the same center. A variable number of visits was performed at each site. Experts agreed that PST should be offered only in the context of genetic counselling to at risk individuals aged 18 or older. Advertised commercial options for DNA testing should be avoided. The protocol should consist of several steps, including a preliminary clinical examination, a pre-test information session, an interval time, the genetic test and a post-test session with the disclosure of the test results, in the context of an experienced multidisciplinary team. Recommendations for best timing were also defined. Protocols for PST in the context of ATTRv can be refined to offer at risk individuals the best chance for early diagnosis and timely treatment start, while respecting autonomous decisions and promoting safe psychological adjustment to the genetic result.

Structural brain anomalies in Cri-du-Chat syndrome: MRI findings in 14 patients and possible genotype-phenotype correlations.

INTRODUCTION: Cri-du-Chat Syndrome (CdCS) is a genetic condition due to deletions showing different breakpoints encompassing a critical region on the short arm of chromosome 5, located between p15.2 and p15.3, first defined by Niebuhr in 1978. The classic phenotype includes a characteristic cry, peculiar facies, microcephaly, growth retardation, hypotonia, speech and psychomotor delay and intellectual disability. A wide spectrum of clinical manifestations can be attributed to differences in size and localization of the 5p deletion. Several critical regions related to some of the main features (such as cry, peculiar facies, developmental delay) have been identified. The aim of this study is to further define the genotype-phenotype correlations in CdCS with particular regards to the specific neuroradiological findings. PATIENTS AND METHODS: Fourteen patients with 5p deletions have been included in the present study. Neuroimaging studies were conducted using brain Magnetic Resonance Imaging (MRI). Genetic testing was performed by means of comparative genomic hybridization (CGH) array at 130 kb resolution. RESULTS: MRI analyses showed that isolated pontine hypoplasia is the most common finding, followed by vermian hypoplasia, ventricular anomalies, abnormal basal angle, widening of cavum sellae, increased signal of white matter, corpus callosum anomalies, and anomalies of cortical development. Chromosomal microarray analysis identified deletions ranging in size from 11,6 to 33,8 Mb on the short arm of chromosome 5. Then, we took into consideration the overlapping and non-overlapping deleted regions. The goal was to establish a correlation between the deleted segments and the neuroradiological features of our patients. CONCLUSIONS: Performing MRI on all the patients in our cohort, allowed us to expand the neuroradiological phenotype in CdCS. Moreover, possible critical regions associated to characteristic MRI findings have been identified.

Late-onset Pompe disease: a genetic-radiological correlation on cerebral vascular anomalies.

Pompe disease is an autosomal recessive disorder in which deficiency of the lysosomal enzyme acid alpha-glucosidase results in the accumulation of glycogen mostly in muscle tissues. Several reports suggest a higher incidence of intracranial vascular abnormalities (IVAs) in this condition, as well as brain microbleeds and cerebral vasculopathy. The aim of our study was to evaluate through neuroimaging studies the incidence of these anomalies in our cohort of late-onset Pompe disease (LOPD) patients asymptomatic for cerebrovascular disease, looking for correlations with clinical and genetic data. We studied 18 LOPD patients with brain magnetic resonance angiography (MRA), or contrast-enhanced computed tomography (CECT). Diameters of individual arteries were measured and compared with average values as proposed in the literature. We found IVAs in 13 of the 18 patients, mostly dilatative arteriopathy affecting the vertebrobasilar system. The anterior circle was involved in seven of the 18 patients. The diameter of the basilar artery at 1 cm was found to correlate both with age (spearman rho, p = 0.037) and disease duration (p = 0.004), but no other statistically significant correlation was documented. The incidence of intracranial dilatative arteriopathy in LOPD was higher than in the general population, confirming the literature data. However, we did not find intracranial aneurysms microbleeds or significant cerebrovascular disease. Abnormalities in the anterior and the posterior circle of Willis correlated with age and disease duration, but not with the severity of muscle/respiratory involvement or with genetic data. Further studies in larger cohorts of patients are needed to confirm these findings.

Nasal powders of thalidomide for local treatment of nose bleeding in persons affected by hereditary hemorrhagic telangiectasia.

In this work nasal powder formulations of thalidomide were designed and studied to be used by persons affected by hereditary hemorrhagic telangiectasia as a complementary anti-epistaxis therapy, with the goal of sustaining the effect obtained with thalidomide oral treatment after its discontinuation for adverse effects. Three nasal powders were prepared using as carriers ß-CD or its more hydrophilic derivatives such as hydropropyl-ß-CD and sulphobutylether-ß-CD and tested with respect to technological and biopharmaceutical features after emission with active and passive nasal powder devices. For all formulated powders, improved dissolution rate was found compared to that of the raw material, making thalidomide promptly available in the nasal environment at a concentration favouring an accumulation in the mucosa. The very limited transmucosal transport measured in vitro suggests a low likelihood of significant systemic absorption. The topical action on bleeding could benefit from the poor absorption and from the fact that about 2-3% of the thalidomide applied on the nasal mucosa was accumulated within the tissue, particularly with the ß-CD nasal powder.

LOPED study: looking for an early diagnosis in a late-onset Pompe disease high-risk population.

OBJECTIVE: A multicentre observational study was aimed to assess the prevalence of late-onset Pompe disease (LOPD) in a large high-risk population, using the dried blood spot (DBS) as a main screening tool. DESIGN/METHODS: 17 Italian neuromuscular centres were involved in the late-onset Pompe early diagnosis (LOPED) study. Inclusion criteria were: (1) age ≥5 years, (2) persistent hyperCKaemia and (3) muscle weakness at upper and/or lower limbs (limb-girdle muscle weakness, LGMW). Acid α-glucosidase (GAA) activity was measured separately on DBS by fluorometric as well as tandem mass spectrometry methods. A DBS retest was performed in patients resulted positive at first assay. For the final diagnosis, GAA deficiency was confirmed by a biochemical assay in skeletal muscle, whereas genotype was assessed by GAA molecular analysis. RESULTS: In a 14-month period, we studied 1051 cases: 30 positive samples (2.9%) were detected by first DBS screening, whereas, after retesting, 21 samples were still positive. Biochemical and molecular genetic studies finally confirmed LOPD diagnosis in 17 cases (1.6%). The median time from the onset of symptoms/signs to diagnosis was 5 years. Among those patients, 35% showed presymptomatic hyperCKaemia and 59% showed hyperCKaemia+LGMW, whereas 6% manifested with LGMW. CONCLUSIONS: LOPED study suggests that GAA activity should be accurately screened by DBS in all patients referring for isolated hyperCKaemia and/or LGMW. A timely diagnosis was performed in five patients with presymptomatic hyperCKaemia, but two had already manifested with relevant changes on muscle morphology and MRI. Consequently, enzyme replacement therapy was started in 14/17 patients, including the 2 patients still clinically presymptomatic but with a laboratory evidence of disease progression.

Radiosensitivity in lymphoblastoid cell lines derived from Shwachman-Diamond syndrome patients.

Shwachman-Diamond syndrome is an autosomal-recessive disorder characterised by bone marrow failure and a cumulative risk of progression to acute myeloid leukaemia. The Shwachman-Bodian-Diamond syndrome (SBDS) gene, the only gene known to be causative of the pathology, is involved in ribosomal biogenesis, stress responses and DNA repair, and the lack of SBDS sensitises cells to many stressors and leads to mitotic spindle destabilisation. The effect of ionising radiation on SBDS-deficient cells was investigated using immortalised lymphocytes from SDS patients in comparison with positive and negative controls in order to test whether, in response to ionising radiation exposure, any impairment in the DNA repair machinery could be observed. After irradiating cells with different doses of X-rays or gamma-rays, DNA repair kinetics and the residual damages using the alkaline COMET assay and the γ-H2AX assay were assessed, respectively. In this work, preliminary data about the comparison between ionising radiation effects in different patients-derived cells and healthy control cells are presented.

Clinical and molecular aspects of 30 patients with late-onset Pompe disease (LOPD): unusual features and response to treatment.

Pompe disease is a rare metabolic disorder, due to mutations in the gene encoding acid alpha-glucosidase (GAA), of which infantile and late-onset forms may occur. Aim of the work was to analyze clinical and laboratory data of a cohort of late-onset Pompe disease (LOPD) patients, collected during the last 15 years and to point out unusual phenotypic/genotypic features as well as enzyme replacement therapy (ERT) responses. We diagnosed 30 LOPD patients; at follow-up, they underwent motor, respiratory, cardiac and muscle MRI evaluations. Motor performances were tested by Walton Gardner-Medwin, GSGC and 6MWT tests. Respiratory function was assessed as FVC% in upright/supine position. LOPD presentations were represented by presymptomatic hyperCKemia (37%), proximal/axial muscle weakness (53%) and respiratory impairment (10%). Median diagnostic delay was 8.6 years (± 8.8). Atypical features were observed in 4 patients: marked distal muscle weakness and severe hearing loss at onset, as well as leukoencephalopathy and mesial temporal sclerosis during the disease course. By GAA sequence analysis, two causing mutations were detected in 22/30 patients, only one in the remaining 8 subjects. Overall, 29/30 patients harbored the common c.-32-13T>G mutation (2 were homozygous). Two new DNA variations were discovered (c.2395C>G, c.1771C>T). 14 patients received ERT for up to 60 months. Our study confirms LOPD clinical and genetic heterogeneity: atypical features may contribute to expand the clinical phenotype highlighting its multi-systemic nature. A timely diagnosis could allow early ERT start. An accurate follow-up is recommended to evaluate treatment responses.

Early onset of a nasal perivascular epithelioid cell neoplasm not related to tuberous sclerosis complex.

Perivascular epithelioid cell neoplasms are a group of rare tumours reported in various organs under a variety of designations. Such tumours are of interest primarily because of the distinctive morphology of their cell population and their immunoreactivity with melanocytic and myoid markers. There is a strong association between perivascular epithelioid cell neoplasms and tuberous sclerosis complex. Perivascular epithelioid cell neoplasms very rarely occur in the upper aero-digestive tract. To date only three cases of nasal perivascular epithelioid cell neoplasms have been reported in the literature. The present report refers to a 22-year old woman, without any stigmata of tuberous sclerosis complex, with early onset of a polypoid nasal mass with pathological and immunohistochemical features entirely compatible with those of a perivascular epithelioid cell neoplasm.

Hepatic sonography in patients with hereditary hemorrhagic telangiectasia hospitalized for epistaxis.

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder characterized by the presence of telangiectasias and arteriovenous malformations in various organs and organ systems, including the liver. The most frequent clinical manifestation of HHT is epistaxis.In 2010 (January-December inclusive) 51 patients with HHT were admitted to the ENT ward of our hospital for epistaxis, and in accordance with routine protocols, all 51 underwent abdominal ultrasonography in our department to detect hepatovascular lesions. They included 27 males (53%) and 24 (47%) females ranging in age from 11 to 86 years (mean 48.5 years). The sample was selected in an arbitrary manner to take maximum advantage of the hospital stay and monitor patients from regions other than our own.Retrospective analysis of the findings from these sonographic examinations revealed hepatic HHT in 27 (53%) of the 51 patients. Nineteen (70%) of these (age range 40-86 years, mean 63) had vascular malformations of various dimensions but no portal hypertension; the other eight (30%) (age range 39-81 years, mean 60) had vascular malformations plus portal hypertension.Our retrospective analysis indicates that a significant number of patients can have unrecognized hepatic involvement; that the appearance of hepatic lesions can be fairly unpredictable, even when the HHT has been diagnosed for years and the patients are already symptomatic; and that the hepatic lesions are frequently progressive. Therefore, regular sonographic follow-up is advisable for patients with HHT.The limitations of this study are related to the small number of patients examined and to the fact that all of them were symptomatic. Further study is therefore needed (especially in asymptomatic patients) to define the indications for hepatic sonography and the optimum examination schedule.Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder characterized by the presence of telangiectasias and arteriovenous malformations in various organs and organ systems, including the liver. The most frequent clinical manifestation of HHT is epistaxis.In 2010 (January­December inclusive) 51 patients with HHT were admitted to the ENT ward of our hospital for epistaxis, and in accordance with routine protocols, all 51 underwent abdominal ultrasonography in our department to detect hepatovascular lesions. They included 27 males (53%) and 24 (47%) females ranging in age from 11 to 86 years (mean 48.5 years). The sample was selected in an arbitrary manner to take maximum advantage of the hospital stay and monitor patients from regions other than our own.Retrospective analysis of the findings from these sonographic examinations revealed hepatic HHT in 27 (53%) of the 51 patients. Nineteen (70%) of these (age range 40­86 years, mean 63) had vascular malformations of various dimensions but no portal hypertension; the other eight (30%) (age range 39­81 years, mean 60) had vascular malformations plus portal hypertension.Our retrospective analysis indicates that a significant number of patients can have unrecognized hepatic involvement; that the appearance of hepatic lesions can be fairly unpredictable, even when the HHT has been diagnosed for years and the patients are already symptomatic; and that the hepatic lesions are frequently progressive. Therefore, regular sonographic follow-up is advisable for patients with HHT.The limitations of this study are related to the small number of patients examined and to the fact that all of them were symptomatic. Further study is therefore needed (especially in asymptomatic patients) to define the indications for hepatic sonography and the optimum examination schedule.

Shwachman-Diamond syndrome and type 1 diabetes mellitus: more than a chance association?

Shwachman-Diamond syndrome is a rare clinical condition consisting of exocrine pancreatic dysfunction, various degree of pancytopenia, and metaphyseal dysplasia. The majority of Shwachman-Diamond syndrome cases result from mutations in the Shwachman-Bodian-Diamond Syndrome gene. To date, type 1 diabetes mellitus has only been reported in 4 independent cases presenting with Shwachman-Diamond syndrome, 3 of them with molecular confirmation of the diagnosis. We describe 2 unrelated patients with clinical and molecular features typical of Shwachman-Diamond syndrome and type 1 diabetes mellitus. In addition, we report the occurrence rate of type 1 diabetes mellitus in the Italian registry for Shwachman-Diamond syndrome, which is low (3.23%) but increased at least 30-fold over the type 1 diabetes mellitus occurrence rate in the general population. No evidence of a direct correlation between Shwachman-Diamond syndrome and type 1 diabetes mellitus have been reported, therefore the presence of both diseases in the same patient might be a chance association, however we suggest that the defects in immune regulation of Shwachman-Diamond syndrome might play a role in the development of type 1 diabetes mellitus.

Twenty-five novel mutations including duplications in the ATP7A gene.

Twenty-five novel mutations including duplications in the ATP7A gene. Menkes disease (MD) and occipital horn syndrome (OHS) are allelic X-linked recessive copper deficiency disorders resulting from ATP7A gene mutations. MD is a severe condition leading to progressive neurological degeneration and death in early childhood, whereas OHS has a milder phenotype with mainly connective tissue abnormalities. Until now, molecular analyses have revealed only deletions and point mutations in both diseases. This study reports new molecular data in a series of 40 patients referred for either MD or OHS. We describe 23 point mutations (9 missense mutations, 7 splice site variants, 4 nonsense mutations, and 3 small insertions or deletions) and 7 intragenic deletions. Of these, 18 point mutations and 3 deletions are novel. Furthermore, our finding of four whole exon duplications enlarges the mutation spectrum in the ATP7A gene. ATP7A alterations were found in 85% of cases. Of these alterations, two thirds were point mutations and the remaining one third consisted of large rearrangements. We found that 66.6% of point mutations resulted in impaired ATP7A transcript splicing, a phenomenon more frequent than expected. This finding enabled us to confirm the pathogenic role of ATP7A mutations, particularly in missense and splice site variants.

Breast cancer and genetics.

Familiar aggregation of breast cancer has been known since Roman times, but it has been discussed in practical terms only from the 19th century. Most of the studies dealing with this issue suggest that the risk is higher in relatives of patients with early onset and that the risk also increases as a function of the bilaterality of the disease or the simultaneous presence of breast cancer and ovarian cancer.A series of epidemiological studies consistently suggest hereditary autosomal dominant transmission with reduced penetrance. Previous epidemiological research and collection of data from families has been used only from the 1990s in order to identify disease genes. The BRCA1 gene was identified as the first gene responsible for hereditary forms of breast cancer and subsequently BRCA2. In 1995 both genes were identified and cloned, and they demonstrated to have only minimal homology. The conclusions deal with genetic counseling and the evaluation of the risk of developing cancer.

Duplication of the pituitary stalk in a patient with a heterozygous deletion of chromosome 14 harboring the thyroid transcription factor-1 gene.

Magnetic resonance imaging of the hypothalamic-pituitary region revealed a duplication of the pituitary stalk in a patient with a heterozygous deletion of chromosome 14 harboring the thyroid transcription factor-1 gene.

Changes in nutritional status and body composition during enzyme replacement therapy in adult-onset type II glycogenosis.

BACKGROUND: In adult glycogen storage disease type II (GSDII), a single-gene mutation causes reduction of the lysosomal enzyme acid alpha-glucosidse. This produces a chronic proximal myopathy with respiratory involvement. Enzyme replacement treatment (ERT) has recently become available and is expected to improve muscle strength. This should result in increased lean body mass. In this study we evaluate body composition and nutritional status in GSDII, and assess whether these parameters changed during treatment. METHODS: Seventeen patients with late-onset GSDII, aged 52.6 +/- 16.8 years, received ERT for >18 months. Dietary habits and metabolic profiles of glucids, lipids, and proteins were assessed. Body composition was calculated using anthropometry and bioelectrical impedence analysis. RESULTS: On inclusion, we found increased fat mass (FM) in five patients in severe disease stage; all had normal body mass index (BMI). FM correlated inversely, and lean mass (LM) directly, with creatine kinase, prealbumin and albumin levels. After treatment, BMI and FM significantly increased, while LM only showed a trend toward increase. Prealbumin and albumin levels increased as early as after the first months of ERT. DISCUSSION: Body mass index value may underestimate FM in patients in severe stage of disease, due to altered body composition. In severely affected patients, laboratory parameters revealed a relative protein malnutrition, that was reversed by ERT, this reflecting restoration of normal muscle metabolic pathways. Increased BMI may indicate a reduction in energy consumption during exercise or respiration, along with clinical improvement.

Enzyme replacement therapy in adult-onset glycogenosis II: is quantitative muscle MRI helpful?

Although it has been shown that muscle magnetic resonance imaging (MRI) improves the phenotypic characterization of patients with neuromuscular disorders and allows accurate quantification of muscle and adipose tissue distribution, to date quantitative MRI has not been used to assess the therapeutic response in clinical trials of neuromuscular diseases. We discuss quantitative MRI findings after a 6-month course of enzyme replacement therapy administered to nine patients with adult-onset glycogenosis II.

The isochromosome i(7)(q10) carrying c.258+2t>c mutation of the SBDS gene does not promote development of myeloid malignancies in patients with Shwachman syndrome.

Shwachman-Diamond syndrome (SDS) is an autosomal recessive disorder, characterized by exocrine pancreatic insufficiency, skeletal abnormalities and bone marrow (BM) dysfunction with an increased risk to develop myelodysplastic syndrome and/or acute myeloid leukaemia (MDS/AML). SDS is caused, in nearly 90% of cases, by two common mutations (that is, c.183_184TA>CT and c.258+2T>C) in exon 2 of the SBDS gene, localized on chromosome 7. Clonal chromosome anomalies are often found in the BM of SDS patients; the most frequent is an isochromosome for long arms of chromosome 7, i(7)(q10). We studied eight patients with SDS carrying the i(7)(q10) who were compound heterozygotes for SBDS mutations. By assessing the parental origin of the i(7)(q10) using microsatellite analysis, we inferred from the results which mutation was present in double dose in the isochromosome. We demonstrate that in all cases the i(7)(q10) carries a double dose of the c.258+2T>C, and we suggest that, as the c.258+2T>C mutation still allows the production of some amount of normal protein, this may contribute to the low incidence of MDS/AML in this subset of SDS patients.

Contrast echocardiography for pulmonary arteriovenous malformations screening: does any bubble matter?

AIMS: To evaluate diagnostic accuracy of contrast echocardiography (CE) as compared with CT, for the screening of pulmonary arteriovenous malformations (PAVMs) in hereditary haemorrhagic telangiectasia (HHT); to evaluate the clinical significance of semi-quantitative analysis of a shunt on CE. METHODS AND RESULTS: A blinded prospective study was conducted in 190 consecutive subjects at risk of HHT who underwent screening for PAVMs, including clinical evaluation, pulse oximetry, standard and CE, and chest multirow CT without contrast medium. A semi-quantitative analysis of the shunt size was performed according to the contrast echo opacification of the left-sided chambers: Grade 0, no bubbles; 1, occasional filling with <20 bubbles; 2, moderate filling; 3, complete opacification. The first 100 patients were compared with 100 controls. A total of 119 (63%) patients had positive CE (32.2% Grade 1, 13.1% Grade 2, 11% Grade 3, 6.3% with patent foramen ovale). The overall diagnostic performance of CE was sensitivity 1.00, specificity 0.49, positive predictive value (PPV) 0.32, negative predictive value (NPV) 1.00. The PPV for the different grades was 0.00 for Grade 1, 0.56 for Grade 2, 1.00 for Grade 3; the NPV of Grade 0 was 1.00. A significant correlation was found between the CE grading and the number of PAVM, and complications (P < 0.0001). CONCLUSION: CE is an extremely sensitive procedure for the detection of PAVMs with substantial clinical impact.

Diagnosis of glycogenosis type II.

The diagnosis of glycogenosis type II is often complicated by the rarity of the condition and the heterogeneity of the clinical manifestations of the disease. It is a progressive, debilitating, and often fatal neuromuscular disorder that manifests as a continuum of clinical phenotypes, which vary with respect to organ involvement, age at onset, and severity. Early diagnosis requires both increased awareness among physicians regarding the clinical characteristics of the disease and fast and reliable acid alpha-glucosidase (GAA) enzyme activity assays to confirm the GAA deficiency. The clinical diagnosis of glycogenosis type II is confirmed by virtual absence (found in infants) and marked reduced activity (found in juveniles and adults) of GAA enzyme in blood samples, cultured fibroblasts, and muscle biopsies. This article specifically highlights the need for early recognition of the clinical manifestation of the disease in infants, juveniles, and adults. Descriptions of the main clinical features of the condition, as well as differential diagnosis are included. In addition, the tests required for a confirmed diagnosis are described, and use of muscle imaging to evaluate muscle pathology is reviewed.

Management and treatment of glycogenosis type II.

Glycogenosis type II is a multisystem disorder that requires management by a multidisciplinary team. The team should include several specialists, such as a metabolic disease specialist or biochemical geneticist, cardiologist, pulmonologist, neurologist, neuromuscular specialist, intensivist, orthopedist, respiratory therapist, physical therapist, occupational therapist, otolaryngologist speech therapist, audiologist, genetic counselor, and a metabolic dietician, who, as a team, will be capable of addressing the different manifestations of the condition. Aspects of functional assessment, rehabilitation, nutritional management, care coordination, nursing, genetic counseling, prenatal diagnosis, and screening are discussed in this article. In addition, treatment of glycogenosis type II is reviewed with attention to emerging therapeutic options.