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Metachromatic leukodystrophy (MLD) is an autosomal recessive lysosomal disorder caused by deficiency of arylsulfatase A (ARSA), leading to an accumulation of sulfatides. Sulfatides have been quantified in urine, dried blood spots (DBS), and tissues of patients with MLD. Newborn screening (NBS) for MLD has already been proposed based on a two-tier approach with the quantification of sulfatides in DBS followed by the quantification of ARSA by liquid chromatography–tandem mass spectrometry (LC–MS/MS). Prenatal screening for MLD is also crucial, and sulfatide quantification in amniotic fluid (AF) can aid diagnosis. The prenatal study was initiated due to a family history of MLD at 19 weeks of gestation. ARSA was quantified in cultured amniocytes. C16:0 sulfatide was quantified by LC-MS/MS in the supernatant of AF. Molecular analysis of the ARSA gene was performed in cultured amniocytes. ARSA was deficient in fetal cells, and C16:0 sulfatides were significantly elevated in comparison to age-matched controls (3-fold higher). Genetic studies identified the c.465+1G>A variant in homozygosis in the ARSA gene. Our study shows that sulfatides can be quantified in the supernatant of AF of MLD fetuses, and it could potentially aid in a faster and more accurate diagnosis of MLD patients.

Niemann-Pick type C (NP-C) is a rare autosomal recessive disorder characterized by storage of unesterified glycolipids and cholesterol in lysosome and/or late endosome due to mutations in either NPC1 or NPC2 gene. This study aims to identify the spectrum of sequence alterations associated to NP-C in individuals with clinical suspicion of this disease. The entire coding region and flanking sequences of both genes associated to NP-C were evaluated in a total of 265 individuals that were referred to our laboratory. Clinical and/or biochemical suspicion of NP-C was confirmed by molecular analysis in 54 subjects. In this cohort, 33 different sequence alterations were identified in NPC1 and one in NPC2. Among those, 5 novel alterations in NPC1 gene were identified as follows: one deletion (p.Lys38_Tyr40del), one frameshift (p.Asn195Lysfs*2), and three missense mutations (p.Cys238Arg, p.Ser365Pro and, p.Val694Met) that are likely to be pathogenic through different approaches, including in silico tools as well as multiple sequence alignment throughout different species. We have also reported main clinical symptoms of patients with novel alterations and distribution of frequent symptoms in the cohort. Findings reported here contribute to the knowledge of mutation spectrum of NP-C, defining frequent mutations as well as novel sequence alterations associated to the disease.

Lysosomal Storage Disorders (LSDs) are characterized by an abnormal accumulation of substrates within the lysosome and comprise more than 50 genetic disorders with a frequency of 1:5000 live births. Nanotechnology may be a promising way to circumvent the drawbacks of the current therapies for lysosomal diseases. The blood circulation time and bioavailability of the enzymes or drugs could be improved by inserting them in nanocarriers, which could decrease and/or avoid the need of frequent intravenous infusions along with the minimization or elimination of associated immunogenic responses. Considering the exposed, we aimed to build monoolein-based nanoparticles stabilized by polysorbate 80 as a smart platform able to reach the central nervous system (CNS) to deliver drugs or enzymes inside lysosomes. We developed and characterized the nanoparticles by dynamic light scattering (DLS), small-angle X-ray scattering (SAXS) and cryogenic transmission electron microscopy (Cryo-TEM). The nanoparticles showed a diameter of 115 nm, which is compatible with in vivo application. The SAXS patterns of the formulations displayed a single broad correlation peak that was fitted to the Teubner-Strey model confirming that disordered bicontinuous structures were obtained. Cryo-TEM images corroborated this finding and showed nanoparticles with size values that are similar to those determined by DLS. Furthermore, the nanoparticles did not present cytotoxicity when they were incubated with human fibroblasts, and demonstrated hemolytic activity proportional to the negative control, proving to be safe for parenteral administration. Through the use of a fluorescent dye to track the nanoparticles inside the cell, we demonstrated that they reached lysosomes after 1 h of treatment. More interestingly, the fluorescent dye was detected in the CNS of mice just after 3 h of treatment. The nanoparticles show great potential to improve the treatment of LSDs with brain impairment, acting as a smart platform to targeted delivery of drugs or enzymes.

β-Cyclodextrin (β-CD) is being considered a promising therapy for Niemann-Pick C (NPC) disease because of its ability to mobilise the entrapped cholesterol from lysosomes, however, a major limitation is its inability to cross the blood-brain barrier (BBB) and address the central nervous system (CNS) manifestations of the disease. Considering this, we aimed to design nanoparticles able to cross the BBB and deliver β-CD into the CNS lysosomes. The physicochemical characteristics of β-CD-loaded nanoparticles were evaluated by dynamic light scattering, small-angle X-ray scattering, and cryogenic transmission electron microscopy. The in vitro analyses were performed with NPC dermal fibroblasts and the β-CD-loaded nanoparticles were tracked in vivo. The nanoparticles showed a mean diameter around 120 nm with a disordered bicontinuous inner structure. The nanoparticles did not cause decrease in cell viability, impairment in the antioxidant enzymes activity, damage to biomolecules or release of reactive species in NPC dermal fibroblasts; also, they did not induce genotoxicity or alter the mitochondrial function in healthy fibroblasts. The β-CD-loaded nanoparticles were taken up by lysosomes reducing the cholesterol accumulated in NPC fibroblasts and reached the CNS of mice more intensely than other organs, demonstrating advantages compared to the free β-CD. The results demonstrated the potential of the β-CD-loaded nanoparticles in reducing the brain impairment of NPC.

Trisomy 18 (T18) and trisomy 13 (T13) are polymalformative syndromes associated with a high rate of spontaneous abortions, intrauterine death, and short postnatal life. This study describes the overall outcome in a country where the therapeutic interruption of pregnancy is not available. The medical records of women with prenatal diagnosis of full trisomy of T13 or T18 between October 1994 and October 2017 were analyzed in order to describe their natural outcomes. Thirteen cases of T13 and 29 cases of T18 were included. The miscarriage rate was 9% for T18 and no cases for T13. Intrauterine fetal death occurred in 46% and 52% of cases for T13 and T18, respectively. The rate of live births for T13 was 54%, and the median survival was one day (95% CI -33.55 - 90.40) and 71% died in the first 24 hours of life. The rate of live births for T18 was 37% and the median survival was two days (95% CI -1.89 - 13.17); 90% of the affected babies died within first week of life. For the affected babies reaching the first year of life and for those who lived longer, multiple invasive and expensive procedures were required, without success in prolonging life beyond 180 days. This large series provides information for professionals and women regarding the natural histories of T13 and T18. Results of this study are consistent with those referenced in the literature, emphasizing the need of structured protocols and guidelines aiming early T13 and T18 diagnosis, prenatal care, gestation/parents follow-up, and counseling processes. For those couples with earlier diagnosis, a better follow-up and counseling during the prenatal care lead to the option for a support or palliative management of the newborn. Finally, when the counseling process is appropriate, it becomes easier to take decisions respecting the parent’s autonomy and to look for better outcomes for both, the mother and the fetus.

OBJETIVO: Descrever a prevalência das malformações encontradas nos fetos com trissomia dos cromossomos 13, 18 e 21, identificando as mais frequentes em cada condição. MÉTODOS: Estudo transversal retrospectivo, com análise dos casos de trissomias dos cromossomos 13, 18 e 21 que foram diagnosticados pelo cariótipo fetal obtido por amniocentese/cordocentese, entre outubro de 1994 e maio de 2014, em um Hospital de Ensino da região Sul do Brasil. Foram descritas as malformações identificadas no exame ultrassonográfico morfológico e, posteriormente, confirmadas em exames do recém-nascido e/ou por necropsia fetal. Os resultados foram analisados por meio do teste de Fisher e da análise de variância (ANOVA). O nível de significância empregado foi 5% (p=0,05). RESULTADOS: Em 840 exames realizados, foram diagnosticados 69 casos de trissomias; nove deles foram excluídos por desfecho ocorrido fora do Hospital de Clínicas de Porto Alegre ou prontuário incompleto, restando 60 casos (nove de trissomia do cromossomo 13, 26 do cromossomo 18 e 25 do cromossomo 21). As cardiopatias ocorreram, na maioria dos casos, nos três grupos; a comunicação interventricular foi mais prevalente, em 66,7% do grupo da trissomia 13. As anomalias gastrintestinais aconteceram mais no grupo da trissomia 18, principalmente a onfalocele (38,5%; p

Mucolipidosis II alpha/beta is an autosomal recessive disorder caused by deficient activity of GlcNAc-1-phosphotransferase. We report the prenatal diagnosis of a fetus who was found to exhibit normal levels of lysosomal enzymes in the amniotic fluid but low levels in amniocytes, and who was found to be heterozygous for the most common GNPTAB mutation. As in some carriers of Mucolipidosis II biochemical abnormalities may hinder prenatal diagnosis, we suggest DNA analysis should be performed whenever possible., Highlights • Biochemical prenatal investigation in amniotic fluid and amniocytes were inconclusive for ML II/III. • DNA analysis showed fetus heterozygous for GNPTAB mutation c.[3503_3504delTC].

Background Niemann-Pick type C (NP-C), one of 50 inherited lysosomal storage disorders, is caused by NPC protein impairment that leads to unesterified cholesterol accumulation in late endosomal/lysosomal compartments. The clinical manifestations of NP-C include hepatosplenomegaly, neurological and psychiatric symptoms. Current diagnosis for NP-C is based on observation of the accumulated cholesterol in fibroblasts of affected individuals, using an invasive and time expensive test, called Filipin staining. Lately, two metabolites that are markedly increased in NP-C patients are arising as biomarkers for this disease screening: 7-ketocholesterol and cholestane-3β,5α,6β-triol, both oxidized cholesterol products. Objective In this work, we aimed to evaluate the performance of cholestane-3β,5α,6β-triol analysis for the screening and monitoring of NPC patients, correlating it with chitotriosidase levels, Filipin staining and molecular analysis. It was investigated 76 non-treated individuals with NP-C suspicion and also 7 patients with previous NP-C diagnosis under treatment with miglustat, in order to verify the cholestane-3β,5α,6β-triol value as a tool for therapy monitoring. Results Considering molecular assay as golden standard, it was verified that cholestane-3β,5α,6β-triol analysis presented 88% of sensitivity, 96.08% of specificity, a positive and negative predictive value calculated in 91.67% and 94.23%, respectively, for the diagnosis of NP-C. Chitotriosidase levels were increased in patients with positive molecular analysis for NP-C. For Filipin staining, it was found 1 false positive, 7 false negative and 24 inconclusive cases, showing that this assay has important limitations for NP-C diagnosis. Besides, we found a significant decrease in cholestane-3β,5α,6β-triol concentrations in NP-C patients under therapy with miglustat when compared to non-treated patients. Conclusion Taken together, the present data show that cholestane-3β,5α,6β-triol analysis has a high potential to be an important NP-C screening assay, and also can be used for therapy monitorization with miglustat in NP-C patients.

Objective The aim of this study was to quantify glycosaminoglycans (GAGs) in amniotic fluid (AF) from an MPS VII fetus compared with age-matched fetuses obtained from normal pregnancies. Method Disaccharides were measured by liquid chromatography tandem mass spectrometry, compared to age-matched controls. Enzyme assay was performed in AF supernatant or cultured amniocytes. GUSB was analyzed by next generation sequencing using Ion Torrent Personal Genome Machine with a customized panel. Results No activity of β-glucuronidase was detected in fetal cells. The pregnancy was spontaneously terminated in the third trimester. Genetic studies identified a homozygous mutation of p.N379D (c.1135A > G) in the GUSB gene. Liquid chromatography tandem mass spectrometry showed that chondroitin sulfate, dermatan sulfate, heparan sulfate, and keratan sulfate levels were markedly increased in the MPS VII AF, compared to those in age-matched control AF (dermatan sulfate, heparan sulfate, and chondroitin-6-sulfate more than 10 × than age-matched controls; chondroitin-4-sulfate and keratan sulfate more than 3 times higher). Conclusion This is the first report of specific GAG analysis in AF from an MPS VII fetus, indicating that GAG elevation in AF occurs by 21 weeks of gestation and could be an additional tool for prenatal diagnosis of MPS VII and potentially other MPS types. © 2017 John Wiley & Sons, Ltd.

Mucopolysaccharidosis IVA (MPS IVA; Morquio A syndrome) is a lysosomal storage disorder caused by a deficient N-acetylgalactosamine-6-sulfate sulfatase activity, leading to cellular storage of undegraded keratan sulfate. Recently enzyme replacement therapy (ERT) was approved for MPS IVA, but some of ERT effects are still unknown. In the present study, we aimed to evaluate the efficacy of elosulfase alfa upon glycosaminoglycan (GAG) storage in peripheral blood white blood cells of patients with MPS IVA treated for 6 months, comparing samples from patients who received weekly infusions of enzyme (ERT-W) versus infusions every other week (ERT-EOW) versus placebo. A significant reduction in GAG storage was observed in both ERT-treated groups, with weekly ERT showing slightly better performance than ERT-EOW.

et al., In some cases Neu-Laxova syndrome (NLS) is linked to serine deficiency due to mutations in the phosphoglycerate dehydrogenase (PHGDH) gene. We describe the prenatal and postnatal findings in a fetus with one of the most severe NLS phenotypes described so far, caused by a homozygous nonsense mutation of PHGDH. Serial ultrasound (US) and pre- and postnatal magnetic resonance imaging (MRI) evaluations were performed. Prenatally, serial US evaluations suggested symmetric growth restriction, microcephaly, hypoplasia of the cerebellar vermis, micrognathia, hydrops, shortened limbs, arthrogryposis, and talipes equinovarus. The prenatal MRI confirmed these findings prompting a diagnosis of NLS. After birth, radiological imaging did not detect any gross bone abnormalities. DNA was extracted from fetal and parental peripheral blood, all coding exons of PHGDH were PCR-amplified and subjected to Sanger sequencing. Sequencing of PHGDH identified a homozygous premature stop codon mutation (c.1297C>T; p.Gln433*) in fetal DNA, both parents (first-cousins) being heterozygotes. Based on previous associations of mutations in this gene with a milder NLS phenotype, as well as cases of serine deficiency, these observations lend further support to a genotype-phenotype correlation between the degree of PHGDH inactivation and disease severity., Grant sponsor: Spanish Ministry of Science and Innovation; Grant number: SAF2013-43365-R; Grant sponsor: The CIBERER Program of Research on Pediatric diseases (ACCI 2012); Grant sponsor: The Brazilian National Council for Research and Development (CNPq); Grant sponsor: Hospital de Clínicas de Porto Alegre (FIPE-HCPA).

Introduction: During the past few decades, the number of diseases identified to be caused by chromosomal microdeletions has increased quickly, bringing a new and crucial role for cytogenetics on the diagnosis of these conditions. The purpose of this study was to identify and characterize chromosomal microdeletions associated with malformation syndromes and intellectual disability. Methods: We retrospectively evaluated a consecutive series of samples from a cohort of 598 subjects with clinical symptoms of a microdeletion syndrome, including the deletion of chromosomes 4p16.3, 5p15.2, 5q35, 7q11.23, 8q24.12, 15q11.2, 16p13.3, 17p13.3, 17p11.2,2, and 22q11.2, as investigated by fluorescence in situ hybridization (FISH). Array-based comparative genomic hybridization (array-CGH) was performed on 25 samples with microdeletions. Results: A total of 598 samples were evaluated from patients whose clinical phenotypes were most indicative of 22q11.2 deletion syndrome (29.10%), Prader-Willi syndrome (23.41%), Angelman syndrome (16.89%), and Williams-Beuren syndrome (14.72%). In 142 of the samples (23.75%), a chromosomal imbalance associated with phenotypic abnormalities was found. The deletion of 7q11.23 was the most frequent (8.03%), followed by del22q11.2 (5.68%) and del15q11.2 (5%). Conclusion: Our study reinforces the idea that the effort to improve the capacity to perform molecular cytogenetic investigations associated with a qualified clinical evaluation is crucial for the detection and precise characterization of submicroscopic chromosome deletions, bringing benefits to patients, relatives, and genetic counselors. It also contributes to the continuing education of cytogeneticists and to the knowledge of chromosomal rearrangements associated with genomic disorders.

Introduction: Mucopolysaccharidosis type II (MPSII) is an X-linked lysosomal disorder caused by deficiency of iduronate-2-sulfatase ( IDS ). In this study, we proposed a new protocol for prenatal diagnosis, using DNA obtained from amniotic fluid cells that did not attach to the bottom of the culture flask after the first medium change. Methods: Four pregnant MPS II carriers were referred to the Medical Genetics Service of Hospital de Clinicas dePorto Alegre for a prenatal diagnosis and identification of the disease, which were performed by polymerase chain reaction (PCR) amplification, restriction fragment length polymorphism, and sequencing according to the mutation previously found in the family. Results: The analysis indicated the absence of mutation in three fetal materials and the presence of mutation in one case. Concomitantly, cytogenetic and biochemical analyses were performed after 12 days of cell culture, and only one case showed absence of enzyme activity, confirming the molecular analysis. Conclusions: This diagnostic protocol designed to provide more robust results and safer genetic counseling suggests that DNA obtained from floating amniotic fluid cells can be used as a source of fetal material to allow a faster alternative for prenatal care through molecular analysis. Determination of IDS gene mutation in fetal amniotic fluid cells together with IDS enzyme activity testing is a rapid, sensitive and accurate method for prenatal diagnosis of MPS II for high-risk pregnant women.

Introdução: pacientes em amenorréia primária com disgenesia gonadal têm níveis elevados de gonadotrofinas e necessitam de avaliação cromossômica. O estudo citogenético (cariótipo) pode ser realizado na gônada ou no sangue periférico. Nos casos de amenorréia primária sem sinal de virilização, a necessidade de investigação adicional do cariótipo da gônada não está estabelecida. Objetivo: revisar os cariótipos de gônadas (ovários) de mulheres com amenorréia primária e compará-los com os resultados do cariótipo no sangue periférico, relacionando-os às características fenotípicas das pacientes. Métodos: foram analisados retrospectivamente os dados clínicos e os cariótipos de doze pacientes atendidas no período de janeiro de 1997 a dezembro de 2003 no Hospital de Clínicas de Porto Alegre. Resultados: nas pacientes incluídas, quando o motivo da investigação foi amenorréia primária sem sinal de virilização, o cariótipo da gônada foi concordante com o cariótipo do sangue periférico nos oito casos avaliados (sete pacientes com cariótipo 46XX e uma paciente com cariótipo 46XY). A paciente oito foi a única com sinal de virilização (hipertrofia de clitóris) e o único caso de cariótipos discordantes. Conclusão: este estudo sugere que o cariótipo de gônada não traz informação adicional ao cariótipo do sangue periférico nas pacientes com amenorréia primária sem sinais de virilização. Até o momento todos os trabalhos publicados tiveram número pequeno de pacientes. A análise da relação custo-benefício pode permitir redução de estresse psicológico para paciente e familiares, bem como redução de custos para as instituições. Background: patients with primary amenorrhea and gonadal dysgenesia have higher serum gonadotrophins and should be submitted to chromosome studies. Karyotype studies may be performed in gonadal tissue or peripheral blood however, it is not yet established if cases of primary amenorrhea without signs of virilization need additional investigation of gonadal karyotype. Purpose: to analize the gonadal karyotypes (ovaries) from patients with primary amenorrhea and compare them to their respective peripheral blood karyotypes. Methods: clinical and karyotype data of 12 patients were retrospectively analyzed from January 1997 to December 2003. Results: when the investigation was indicated for primary amenorrhea without signs of virilization, the gonadal and peripheral blood karyotypes were concordant in 8 cases (7 cases 46XX and 1 case 46XY). One patient with virilization signs was the only case of discordant karyotype. Conclusion: the present study suggests that the gonadal karyotype does not bring additional information to peripheral blood karyotype in patients with amenorrhea and no signs of virilization. Although all previous studies had a small number of patients, it seems advisable to investigate the gonadal karyotype in patients with signs of virilization. The cost-benefit analysis could allow cost and stress reduction for patients, family and institutions.

Objective To investigate lysosomal storage diseases (LSD) in cases of nonimmune hydrops fetalis (NIHF). Methods Thirty-three cases of NIHF were investigated, 28 in the prenatal period and 5 in hydropic newborns. In addition to a general investigation for NIHF, specific enzymatic analyses for the detection of LSD were performed. Results In our sample, we detected five patients (15%) with LSD, each patient having one of the following diseases: mucolipidosis, Niemann–Pick disease, galactosialidosis, sialidosis and mucopolysaccharidosis type IV A. Conclusion Although LSDs are rare disorders as a group, they should be considered as a possible cause of NIHF, even in the absence of consanguinity or of a previous family history. By excluding the more frequent causes of NIHF, an LSD investigation assists in clarifying the etiology of many hydropic cases, making more appropriate genetic counseling for parents possible. Copyright © 2004 John Wiley & Sons, Ltd.

OBJETIVO: Identificar a etiologia da hidropisia fetal não imune em gestantes diagnosticadas e encaminhadas para acompanhamento pré-natal. MÉTODOS: Estudo retrospectivo com análise dos casos de hidropisia fetal não imune que foram acompanhados entre março de 1992 e dezembro de 2011. Os casos tiveram confirmação diagnóstica pela presença de edema de subcutâneo fetal (≥5 mm) com derrame em pelo menos uma cavidade serosa por meio da ultrassonografia obstétrica, e a investigação etiológica foi realizada com pesquisa citogenética (cariótipo), infecciosa (sífilis, parvovírus B19, toxoplasmose, rubéola, citomegalovírus, adenovírus e herpes simples), hematológica e metabólica (erros inatos), além de com ecocardiografia fetal. Foram excluídas as gestações gemelares. A análise estatística foi efetuada pelo teste do χ2 para aderência (software R 2.11.1). RESULTADOS: Foram incluídas 116 pacientes com hidropisia fetal não imune, sendo que 91 casos (78,5%) tiveram a etiologia elucidada e 25 casos (21,5%) foram classificados como causa idiopática. A etiologia cromossômica foi a que apresentou maior número de casos, totalizando 26 (22,4%), seguida da etiologia linfática com 15 casos (12,9%, sendo 11 casos de higroma cístico), da etiologia cardiovascular e da infecciosa com 14 casos cada (12,1%). Os demais casos tiveram etiologia torácica em 6,9% (oito casos), síndromes malformativas em 4,3% (cinco casos), tumores extratorácicos em 3,4% (quatro casos), metabólica em 1,7% (dois casos), hematológica, gastrintestinal e geniturinária em 0,9% cada (um caso cada). No período pós-natal, foram seguidos 104 casos por até 40 dias de vida, 12 casos tiveram morte fetal intrauterina. A sobrevida desses 104 recém-nascidos foi de 23,1% (24 sobreviveram). CONCLUSÃO: a etiologia da hidropisia diagnosticada na gestação deve tentar ser esclarecida, uma vez que está associada a um amplo espectro de doenças. É especialmente importante para determinar se uma condição potencialmente tratável está presente e para identificar doenças com risco de recorrência em futuras gestações para aconselhamento pré-concepcional adequado. PURPOSE: To identify the etiology of nonimmune hydrops fetalis cases in pregnant women diagnosed and referred for prenatal care. METHODS: Retrospective analysis of cases with nonimmune hydrops fetalis that were monitored between March 1992 and December 2011. Diagnosis was confirmed by the presence of fetal subcutaneous edema (≥5 mm) with effusion in at least one serous cavity using obstetric ultrasound, and etiological investigation was conducted with cytogenetic (karyotype), infectious (syphilis, parvovirus B19, toxoplasmosis, rubella, cytomegalovirus, adenovirus and herpes simplex), hematologic and metabolic (inborn errors) analysis and fetal echocardiography. Twin pregnancies were excluded. Statistical analysis was performed using the χ2 test for adhesion (software R 2.11.1). RESULTS: We included 116 patients with nonimmune hydrops fetalis; the etiology was elucidated in 91 cases (78.5%), while 25 cases (21.5%) were classified as idiopathic. Most cases had a chromosomal etiology, for a total of 26 cases (22.4%), followed by lymphatic etiology with 15 cases (12.9% with 11 cases of cystic hygroma), and cardiovascular and infectious etiology with 14 cases each (12.1%). In the remaining cases, the etiology was thoracic in 6.9% (eight cases), malformation syndromes in 4.3% (five cases), extrathoracic tumors in 3.4% (four cases), metabolic in 1.7% (two cases), and hematologic, gastrointestinal and genitourinary in 0.9% (one case each). During the postnatal period, 104 cases were followed up until the 40th day of life, and 12 cases had intrauterine fetal death. The survival rate of these 104 newborns was 23.1% (24 survived). CONCLUSION: An attempt should be made to clarify the etiology of hydrops diagnosed during pregnancy since the condition is associated with a wide spectrum of diseases. It is especially important to determine whether a potentially treatable condition is present and to identify disease at risk for recurrence in future pregnancies for adequate pre-conception counseling.

To identify the etiology of nonimmune hydrops fetalis cases in pregnant women diagnosed and referred for prenatal care.Retrospective analysis of cases with nonimmune hydrops fetalis that were monitored between March 1992 and December 2011. Diagnosis was confirmed by the presence of fetal subcutaneous edema (≥ 5 mm) with effusion in at least one serous cavity using obstetric ultrasound, and etiological investigation was conducted with cytogenetic (karyotype), infectious (syphilis, parvovirus B19, toxoplasmosis, rubella, cytomegalovirus, adenovirus and herpes simplex), hematologic and metabolic (inborn errors) analysis and fetal echocardiography. Twin pregnancies were excluded. Statistical analysis was performed using the χ² test for adhesion (software R 2.11.1).We included 116 patients with nonimmune hydrops fetalis; the etiology was elucidated in 91 cases (78.5%), while 25 cases (21.5%) were classified as idiopathic. Most cases had a chromosomal etiology, for a total of 26 cases (22.4%), followed by lymphatic etiology with 15 cases (12.9% with 11 cases of cystic hygroma), and cardiovascular and infectious etiology with 14 cases each (12.1%). In the remaining cases, the etiology was thoracic in 6.9% (eight cases), malformation syndromes in 4.3% (five cases), extrathoracic tumors in 3.4% (four cases), metabolic in 1.7% (two cases), and hematologic, gastrointestinal and genitourinary in 0.9% (one case each). During the postnatal period, 104 cases were followed up until the 40th day of life, and 12 cases had intrauterine fetal death. The survival rate of these 104 newborns was 23.1% (24 survived).An attempt should be made to clarify the etiology of hydrops diagnosed during pregnancy since the condition is associated with a wide spectrum of diseases. It is especially important to determine whether a potentially treatable condition is present and to identify disease at risk for recurrence in future pregnancies for adequate pre-conception counseling.

The development of conventional cytogenetic techniques in the 50’s leaded to a rapid increase of the knowledge on the etiology of malformation syndromes, being chromosomal anomalies reported as the most common genetic condition in humans (Pena, 1998). Around 2-3% of newborns may have congenital malformations, and from those, just 20% have an established etiology (genetic or environmental), being 80% of these multifactorial or unknown (Stevenson & Hall, 2006). But this is only the tip of the iceberg, as probably half of the human concepts may have some kind of chromosomal defect (A. Boue & J. Boue, 1973), indicating that cytogenetic analysis is fundamental for the investigation of these cases. Since the 70’s, prenatal diagnosis for detecting cytogenetic abnormalities has become a routine procedure in many countries, and an important tool for the prevention of birth of handicapped children (A. Milunsky & J. Milunsky, 1998). Cytogenetic analysis is an important component of invasive prenatal diagnosis as chromosomal abnormalities are detected in about 1 in 200 newborns and constitute a major cause of mental retardation and congenital malformations (Shaffer & Lupski, 2000). Microscopic chromosome analysis of cultured cells has been regarded as the gold standard method for prenatal diagnosis, since its first application to prenatal testing in 1966 by Steele and Breg (Steele & Breg, 1966) and the routine use of chromosome banding analysis in 1970s. Karyotyping has proved to be highly reliable for diagnosis of numerical chromosome abnormalities and structural rearrangements in fetal cells obtained invasively by either amniocentesis in the second trimester of pregnancy, or chorionic villus sampling (CVS) in the first trimester, since the early 1980s. The diagnostic accuracy of karyotyping fetal cells from cultured amniotic fluid (AF) has been found to be 99.4%-99.8%, and that of CVS 97.5-99.6%. However, the main limitation of karyotyping is the requirement of a cell culture, resulting in a period of 10-14 days for obtaining the final results (Bui, 2007). Furthermore, the success of cell culture depends on many factors: very good laboratory conditions for tissue culture, technician’s experience, and satisfactory cell growth with good quality of metaphases. Unfortunately, due to failure in one of these steps the whole process becomes jeopardized.

The Contribution of Molecular Techniques in Prenatal Diagnosis and Post mortem Fetus with Multiple Malformation

Com o desenvolvimento da citogenética convencional, a partir da metade do século passado, houve um enorme crescimento no entendimento da etiologia das síndromes malformativas, sendo as anomalias cromossômicas reconhecidas como a causa genética mais freqüente dos defeitos congênitos. Assim sendo, a investigação de aberrações cromossômicas através do cariótipo se tornou uma rotina na investigação das malformações e de outras condições. Desde os anos 70, quando o diagnóstico pré-natal para a detecção de anomalias cromossômicas no feto foi estabelecido, este tem se tornado uma prática usual em muitos países, e uma importante ferramenta para o aconselhamento genético. A introdução da ultra-sonografia pré-natal na obstetrícia permitiu a identificação precoce de fetos com malformações, os quais têm grande probabilidade de serem portadores de alguma anormalidade cromossômica. O conhecimento da etiologia de sua doença é fundamental para diminuir a ansiedade da família e para tomada de decisões sobre a gestação em curso e sobre gestações futuras. Foi realizado um estudo retrospectivo de 18 anos (1989-2007) que teve como objetivos gerais: estimar a freqüência das anormalidades cromossômicas mais comuns através do cariótipo convencional e suas indicações para as gestantes do Hospital de Clínicas de Porto Alegre (artigo 1). Embora o cariótipo seja considerado o exame padrão ouro para este tipo de investigação, o mesmo possui algumas limitações. Entre elas se destaca a dependência de uma cultura de células, o que significa uma espera de 10 a 14 dias para se obter um resultado, tempo este precioso para a família e para a gestante. Além disto, corre-se o risco de perda da cultura por contaminação ou falta de crescimento celular, e com isso nenhum resultado é atingido, permanecendo a família sem um esclarecimento sobre a situação. Na tentativa de solucionar estes problemas, nesta tese, também foi proposta uma continuação do estudo (de 2006 a 2008) em fetos com múltiplas malformações, para testar a aplicação de técnicas moleculares, como QF-PCR e MLPA em diferentes materiais fetais (artigo 2). Ainda, quando a coleta de materiais tradicionais como líquido amniótico, ou biópsia de vilosidades coriônicas, eram impossíveis de se coletar por alguma dificuldade, incluindo os problemas morfológicos do feto, materiais alternativos, como urina, foram obtidos para se testar sua utilidade para se atingir o diagnóstico citogenético. Os achados citogenéticos relatados no artigo 1 foram compatíveis com os da literatura, sendo a trissomia do 21 a anormalidade cromossômica mais freqüentemente detectada no pré-natal. Entretanto, como o risco de recorrência desta síndrome foi zero neste estudo, um filho anterior com síndrome de Down foi considerado uma indicação fraca, sendo priorizadas para a realização do exame outras famílias carentes de maior risco. Por outro lado, com a técnica de MLPA (artigo 2) não foram obtidos resultados satisfatórios, provavelmente porque as amostras não permitiam obter DNA na qualidade necessária para esse procedimento. Com a técnica de QF-PCR pode-se obter 30 resultados (alguns parciais) nas 50 amostras coletadas. O estudo citogenético convencional de 13 amostras em que materiais diversos dos usuais foram empregados teve 100% de sucesso. Com a aplicação desse arsenal de técnicas, a chance de se obter uma informação citogenética ficou bem maior, diminuindo a ansiedade do casal e auxiliando nas suas decisões reprodutivas. With the development of conventional cytogenetic techniques, since the second half of the last century, there was an enormous growth in knowledge of the etiology of malformed syndromes, being the chromosomal abnormalities considered the most common genetic causes of congenital defects. Therefore, the investigation of chromosomal aberrations by karyotype became a routine in the investigation of the malformations and many other conditions. Since the 70's, when prenatal diagnosis to detect chromosomal abnormalities in the fetus was set up, this became usual practice in many countries, and an important tool for genetic counseling. The introduction of the ultrasound in the obstetrician practice allowed the early identification of the malformed fetus, which has a great probability of being a carrier of some chromosomal aberration. The knowledge of the etiology of the disease is essential to reduce the anxiety of the family and to plan future pregnancies. From 1989 to 2007, 905 pregnant women from Hospital de Clinicas de Porto Alegre had an investigation for their fetus conditions by conventional karyotypes. With this information, a study was made which the main objectives were: to estimate the frequency of the most common chromosomal abnormalities and to estimate the most frequent indications that lead those women to make this invasive procedure (manuscript 1). Although the karyotype is considered the gold standard test for this type of research, it has some limitations, among them: the necessity of a cell culture, which means an expected time between 10 to 14 days to obtain the desired result, and time is a very precious aspect in pregnancy. Moreover, there is a risk of loss of culture because of contamination or lack of cell growth, leaving the family without a result. In an attempt to solve these problems, we proposed another study (from 2006 to 2008) to check the application of molecular techniques such as MLPA and QF-PCR in different malformed fetal materials (manuscript 2). Still, when the collection of traditional materials such as amniotic fluid, blood cord or chorionic villus biopsy were impossible to collect because of morphological problems on the malformed fetus, other alternative materials such as urine or intraperitoneal fluid were collected in an attempt to test these materials as a manner to reach the cytogenetic diagnosis. Our cytogenetics findings were similar to the literature, being trisomy 21 the most frequent chromosomal abnormalities. On the other hand, we did not find any recurrent case of this syndrome, so the indication for doing the exam, as having a previous child with Down syndrome, stayed as a weak indication that comes after others priorities, like pregnancies with greater risks. When we tried to introduce the MLPA technique, we did not achieve satisfactory results, probably because the samples were not suitable for good quality of DNA extraction. We then applied QF-PCR, and obtained 30 results (some partials) from 50 samples collected. The karyotype results of 13 samples from additional materials, not commonly used elsewhere, achieved 100% of success. With all these alternatives techniques, the chance to achieve a diagnosis was much higher, reducing the anxiety of the couple and helping the family to make decisions for futures pregnancies.

The study of the fetal karyotype became an important tool for the fetal diagnosis of genetic diseases in the 1970s. Although application of this test has remained very restricted in Brazil, we had 905 referrals for prenatal fetal karyotyping between 1989 and 2007. In 879 cases, a fetal karyotype was obtained. We detected 74 abnormal karyotypes (8.4%), the majority being found when the prior indication was fetal malformation. When obtaining amniotic fluid or chorionic villus samples was difficult, alternative fetal materials (urine, cystic hygroma, cystic lung, intreperitoneal and cerebrospinal fluids) were collected and we had success in obtaining karyotypes in all 13 cases. Although, the option of terminating abnormal pregnancies does not legally exist in Brazil, the information gained in assessing the prognosis of on-going pregnancies or estimating recurrence risks justifies prenatal diagnosis of chromosome abnormalities. We conclude that, in keeping with the policy in most other countries, prenatal cytogenetic analysis is strongly recommended in high-risk pregnancies for fetal abnormalities. However, the unique aspect of this type of study is not its rarity in world terms, but its rarity in Brazil. This argues that Brazilian health policy on prenatal diagnosis requires reforming to make it much more widely available within the public health care sector.

OBJETIVO: O desenvolvimento de técnicas para diagnosticar as condições genéticas intra-útero foi um grande avanço na genética clínica, mudando a perspectiva reprodutiva de famílias de risco. No Hospital de Clínicas de Porto Alegre (HCPA), o programa de diagnóstico pré-natal (DPN) de anomalias congênitas faz parte do Grupo de Medicina Fetal, que é composto por uma equipe multidisciplinar, cuja meta principal é estudar, analisar, diagnosticar e aconselhar as gestantes de alto risco. O trabalho apresentado aqui tem como objetivos revisar os principais procedimentos de diagnóstico pré-natal, descrever a nossa amostra e os exames que são oferecidos às nossas gestantes. MATERIAIS E MÉTODOS: De janeiro de 1989 a julho de 2001, foram cariotipadas 613 gestações, realizadas investigações enzimáticas em 86 casos e em 4 foram realizados estudos moleculares em material fetal. Um total de 1.378 novos casos foram avaliados no ambulatório de DPN do HCPA, de julho de 1993 a julho de 2001, para aconselhamento genético reprodutivo. RESULTADOS: O diagnóstico pré-natal de cromossomopatias realizado no HCPA atingiu uma taxa de crescimento de culturas de 98%, índice semelhante ao dos países desenvolvidos. CONCLUSÕES: O diagnóstico pré-natal é um importante recurso para as famílias com risco de anomalia fetal. Novas técnicas de diagnóstico estão em implantação no HCPA, e poderão contribuir ainda mais para o atendimento dessas famílias. Apresentamos também os aspectos éticos envolvidos e algumas perspectivas futuras na área do diagnóstico pré-natal de anormalidades congênitas. OBJECTIVE: The development of laboratorial techniques for the prenatal diagnosis of genetic diseases was a great step for clinical genetics, changing reproductive perspectives of high risk families. At Hospital de Clínicas de Porto Alegre (HCPA), the prenatal diagnosis program is part of the Fetal Medicine Group, which includes several professionals of different areas. The main objective of this group is to study, evaluate, diagnose and advice high risk pregnant women. The aim of the present study is to review the main procedures for the prenatal diagnosis and to show the results of our sample regarding the laboratory analysis offer to the pregnant women. MATERIALS AND METHODS: From January 1989 to July 2001, karyotypes were performed for 613 pregnancies, metabolic studies were carried out in 86 pregnancies and molecular analysis was performed for four cases. Prenatal genetic counseling was given to 1,378 families. RESULTS: The prenatal diagnosis of genetic diseases accomplished at HCPA reached a culture growth rate of 98%, which is similar to the result of developed countries. CONCLUSIONS: The prenatal diagnosis is an important tool for the families that are likely to have fetal anomalities. New techniques of diagnosis are being introduced at HCPA, and they will contribute even more to the treatmento of these families. Future prospectives and ethical aspects for prenatal diagnosis are also discussed.

BACKGROUND To define the normal values of amniotic fluid alphafetoprotein in pregnant women, whose gestational ages range from 14 to 21 weeks, in the Hospital de Clinicas de Porto Alegre. MATERIAL AND METHOD One hundred thirty seven women with indication for amniocentesis were studied. The alphafetoprotein was measured in all samples using enzyme immunoassay. One hundred and nine normal pregnancies were selected. All of these fetuses had normal karyotype and had no malformation. They were not twins and their amniotic fluid samples were not bloody. These samples were divided by their gestational ages. Then the medians of the alphafetoprotein values and their multiples were calculated. RESULTS The medians of alphafetoprotein (KUI/ml) for each gestational age were as follows: 14 weeks: 16.32; 15 weeks: 14.36; 16 weeks: 13.43; 17 weeks: 10.93; 18 weeks: 8.22; 19 weeks: 7.35; 20 weeks: 5.62; 21 weeks: 4.47. CONCLUSION The establishment of alphafetoprotein normal values in our service allows us to use this assay for patients at risk of neural tube defects. It also makes possible to analyze samples sent for cytogenetic or metabolic studies, in order to identify elevated levels of alphafetoprotein, so that these fetuses could have a more detailed sonography study to look for malformations.

Trisomy 18 (T18) and trisomy 13 (T13) are polymalformative syndromes associated with a high rate of spontaneous abortions, intrauterine death, and short postnatal life. This study describes the overall outcome in a country where the therapeutic interruption of pregnancy is not available. The medical records of women with prenatal diagnosis of full trisomy of T13 or T18 between October 1994 and October 2017 were analyzed in order to describe their natural outcomes. Thirteen cases of T13 and 29 cases of T18 were included. The miscarriage rate was 9% for T18 and no cases for T13. Intrauterine fetal death occurred in 46% and 52% of cases for T13 and T18, respectively. The rate of live births for T13 was 54%, and the median survival was one day (95% CI -33.55 - 90.40) and 71% died in the first 24 hours of life. The rate of live births for T18 was 37% and the median survival was two days (95% CI -1.89 - 13.17); 90% of the affected babies died within first week of life. For the affected babies reaching the first year of life and for those who lived longer, multiple invasive and expensive procedures were required, without success in prolonging life beyond 180 days. This large series provides information for professionals and women regarding the natural histories of T13 and T18. Results of this study are consistent with those referenced in the literature, emphasizing the need of structured protocols and guidelines aiming early T13 and T18 diagnosis, prenatal care, gestation/parents follow-up, and counseling processes. For those couples with earlier diagnosis, a better follow-up and counseling during the prenatal care lead to the option for a support or palliative management of the newborn. Finally, when the counseling process is appropriate, it becomes easier to take decisions respecting the parent’s autonomy and to look for better outcomes for both, the mother and the fetus.