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- Acroparestesias, Diarreia e Dor Abdominal Recorrente – a Importância do “Awareness” no Diagnóstico da Doença RaraPublication . Freitas, J; Ferreira, AC; Vieira, JP; Candeias, F; Brito, MJ; Ramos, M; Farela Neves, J; Oliveira, L; Antunes, D; Sequeira, SIntrodução: A doença de Anderson-Fabry é uma doença hereditária ligada ao cromossoma X causada pela deficiência da enzima lisossomal alfa-galactosidase com acumulação de globotriaosilceramida e comprometimento multissistémico progressivo. No sexo masculino, manifesta-se geralmente na infância e adolescência com acroparestesias, angioqueratomas e sintomas gastrointestinais, evoluindo na idade adulta precoce com complicações cardíacas, neurológicas e renais. Caso clínico: Jovem de 14 anos, sexo masculino, internado por infeção respiratória. Na história clínica constatou-se quadro com cinco anos de evolução de dor abdominal intermitente, diarreia crónica e episódios recorrentes de dor nas mãos e pés, tipo queimadura, agravados pela febre. O tio materno tinha um quadro clínico semelhante. Foi feita investigação reumatológica, gastrointestinal, auto-imune, neurológica e genética, mas foi o “awareness” diagnóstico para esta entidade que motivou o pedido da atividade enzimática da alfa-galactosidase A e confirmou o diagnóstico de doença de Anderson-Fabry. O estudo molecular do gene GLA revelou, em hemizigotia, a mutação c.195-1G>A. O estudo familiar confirmou a doença no tio materno e em mais um familiar do sexo masculino e três do sexo feminino Comentários: O diagnóstico da doença de Anderson-Fabry é frequentemente tardio devido à raridade da doença, inespecificidade das manifestações iniciais e ao vasto espectro de diagnósticos diferenciais. O diagnóstico precoce é importante pela intervenção na progressão da doença com terapêutica enzimática de substituição. O rastreio familiar é fundamental para a detecção de casos pré-sintomáticos e sintomáticos ainda não diagnosticados.
- AP4S1 Splice-Site Mutation in a Case of Spastic Paraplegia Type 52 with PolymicrogyriaPublication . Carmona, S; Marecos, C; Amorim, M; Ferreira, AC; Conceição, C; Brás, J; Duarte, ST; Guerreiro, RHereditary spastic paraplegias (HSPs) are a group of rare inherited neurodegenerative disorders that result from primary retrograde dysfunction of the long descending fibers of the corticospinal tract, causing lower limb spasticity and muscular weakness. This group of diseases has a heterogeneous clinical presentation. An extensive list of associated genes, different inheritance patterns, and ages at onset have been reported in HSPs.1 Spastic paraplegia type 52 (SPG52) is an autosomal recessive disease caused by AP4S mutations. The disease is characterized by neonatal hypotonia that progresses to hypertonia and spasticity in early childhood, developmental delay, mental retardation, and poor or absent speech. Febrile or afebrile seizures may also occur.
- Birt-Hogg-Dubé SyndromePublication . Lencastre, A; Ponte, P; Apetato, M; Nunes, L; Lestre, SA 45-year-old woman with a history of renal carcinoma was observed for facial, cervical and truncal flesh-colored papules. Relatives had similar skin findings and a brother had repeated episodes of pneumothorax. The computerized tomography scan revealed multiple cysts on both lungs. A skin biopsy revealed a perifollicular fibroma. The clinical diagnosis of Birt-Hogg-Dubé syndrome (BHDS) was corroborated by identification of a novel frameshift c.573delGAinsT (p.G191fsX31) mutation in heterozygosity on exon 6 of the folliculin gene. The presence of multiple and typical benign hair follicle tumors highlights the role of the dermatologist in the diagnosis of this rare genodermatosis that is associated with an increased risk of renal cell cancer and pulmonary cysts, warranting personal and familial follow-up and counseling.
- Caracterização de Crianças com Distúrbio do Espectro da Neuropatia Auditiva e sua ReabilitaçãoPublication . Mariano, M; Correia, I; Nunes, S; Cunha, I; Sousa, H; Kay, T; Barros, EObjectivos: Identificar e caracterizar os casos pediátricos de Distúrbio do Espectro da Neuropatia Auditiva (DENA) e analisar a sua reabilitação. Desenho do Estudo: Estudo observacional descritivo. Material e Métodos: Análise dos processos clínicos de 671 doentes avaliados em primeira consulta de reabilitação auditiva pediátrica entre 2012 e 2019. Dos 467 casos de hipoacusia sensorioneural, incluíram-se aqueles que apresentavam PEATC sem resposta ou com resposta marcadamente anormal e OEAs presentes e/ou limiares tonais desproporcionais aos resultados electrofisiológicos. Obtiveram-se 12 casos de DENA. Resultados: A prevalência de DENA foi 2,6%. A maioria dos casos apresentou factores de risco para hipoacusia. Os resultados audiométricos foram heterogéneos e flutuantes. Quatro crianças foram reabilitadas com prótese auditiva e três com implante coclear. Conclusões: O DENA é uma condição rara, associada a vários factores de risco e de diagnóstico e abordagem desafiantes. A reabilitação auditiva tem de ser personalizada e guiada pelo desempenho funcional da criança.
- A Case of Late-Diagnosed Ovotesticular Disorder of Sex DevelopmentPublication . Knoblich, M; Pratas Vital, V; Cardoso, D; Alves, F; Catela Mota, F; Lopes, L; Kay, T; Casella, PWe report acase of!ovotesticular disorder of sex development!(DSD) with ambiguous genitalia, 46XX presenting the clinical, laboratory, imaging and operative findings and highlighting the pertinent features of this case. Results of hormonal, genetic testing and histopathology findings are reviewed. Diagnosis of true hermaphroditism is well defined and the condition can be recognized even prenatally. Conservative gonadal surgery is the procedure of choice after the diagnosis of true hermaphroditism, if the risk of a gonadal malignancy is low. Continued follow-up is necessary because of the multiple psychological, gynecological and urological problems encountered postpubertally by these patients.
- Clinical and Molecular Characterization of Diastrophic Dysplasia in the Portuguese PopulationPublication . Barbosa, M; Sousa, AB; Medeira, A; Lourenço, T; Saraiva, J; Pinto-Basto, J; Soares, G; Fortuna, AM; Superti-Furga, A; Mittaz, L; Reis-Lima, M; Bonafé, LSLC26A2-related dysplasias encompass a spectrum of diseases: from lethal achondrogenesis type 1B (ACG1B; MIM #600972) and atelosteogenesis type 2 (AO2; MIM #256050) to classical diastrophic dysplasia (cDTD; MIM #222600) and recessive multiple epiphyseal dysplasia (rMED; MIM #226900). This study aimed at characterizing clinically, radiologically and molecularly 14 patients affected by non-lethal SLC26A2-related dysplasias and at evaluating genotype-phenotype correlation. Phenotypically, eight patients were classified as cDTD, four patients as rMED and two patients had an intermediate phenotype (mild DTD - mDTD, previously 'DTD variant'). The Arg279Trp mutation was present in all patients, either in homozygosity (resulting in rMED) or in compound heterozygosity with the known severe alleles Arg178Ter or Asn425Asp (resulting in DTD) or with the mutation c.727-1G>C (causing mDTD). The 'Finnish mutation', c.-26+2T>C, and the p.Cys653Ser, both frequent mutations in non-Portuguese populations, were not identified in any of the patients of our cohort and are probably very rare in the Portuguese population. A targeted mutation analysis for p.Arg279Trp and p.Arg178Ter in the Portuguese population allows the identification of approximately 90% of the pathogenic alleles.
- Collagen Type IV-Related Nephropathies in Portugal: Pathogenic COL4A5 Mutations and Clinical Characterization of 22 FamiliesPublication . Nabais Sá, MJ; Sampaio, S; Oliveira, A; Alves, S; Moura, CP; Silva, SE; Castro, R; Araújo, JA; Rodrigues, M; Neves, F; Seabra, J; Soares, C; Gaspar, MA; Tavares, I; Freitas, L; Sousa, TC; Henriques, AC; Costa, FT; Morgado, E; Sousa, FT; Sousa, JP; da Costa, AG; Filipe, R; Garrido, J; Montalban, J; Ponce, P; Alves, R; Faria, B; Carvalho, MF; Pestana, M; Carvalho, F; Oliveira, JPAlport syndrome (AS) is caused by pathogenic mutations in the genes encoding α3, α4 or α5 chains of collagen IV (COL4A3/COL4A4/COL4A5), resulting in hematuria, chronic renal failure (CRF), sensorineural hearing loss (SNHL) and ocular abnormalities. Mutations in the X-linked COL4A5 gene have been identified in 85% of the families (XLAS). In this study, 22 of 60 probands (37%) of unrelated Portuguese families, with clinical diagnosis of AS and no evidence of autosomal inheritance, had pathogenic COL4A5 mutations detected by Sanger sequencing and/or multiplex-ligation probe amplification, of which 12 (57%) are novel. Males had more severe and earlier renal and extrarenal complications, but microscopic hematuria was a constant finding irrespective of gender. Nonsense and splice site mutations, as well as small and large deletions, were associated with younger age of onset of SNHL in males, and with higher risk of CRF and SNHL in females. Pathogenic COL4A3 or COL4A4 mutations were subsequently identified in more than half of the families without a pathogenic mutation in COL4A5. The lower than expected prevalence of XLAS in Portuguese families warrants the use of next-generation sequencing for simultaneous COL4A3/COL4A4/COL4A5 analysis, as first-tier approach to the genetic diagnosis of collagen type IV-related nephropathies.
- Delecção 1p36 – A Síndrome Não Explica Tudo…Publication . Fitas, AL; Gonçalves, R; Brito, MJ; Kay, T; Sequeira, SIntrodução: A criança com co-morbilidade grave é um premente desafio diagnóstico, cujo sucesso depende de uma abordagem multi-disciplinar. A síndrome de delecção 1p36, microdelecção subtelomérica de apresentação clínica pleiotrópica e multissistémica, pode incluir atraso do desenvolvimento psicomotor, alterações cardíacas, neurológicas e gastrointestinais. Caso Clínico: Filha única de pais não consanguíneos, PNV sem vacinação anti pneumocócica, com múltiplos internamentos: choque cardiogénico com miocardiopatia dilatada (3M), sépsis a S. aureus e Streptococcus do grupo G (5M) e várias intercorrencias infecciosas (varicela, gastrenterite, bronquiolite, febre sem foco). Aos 22 meses é reinternada por choque séptico com falência multi-orgânica por Streptococcus pneumoniae (serotipo 23-F), complicada de osteomielite dos ossos do antebraço e abcesso abdominal com necessidade de cirurgia. Pelos antecedentes e gravidade desta sépsis pneumocócica investigou-se eventual imunodeficiência identificando-se asplenia, confirmada por corpos de Howell-Jolly, TC abdominal e laparotomia. Retrospectivamente, para além da miocardiopatia havia má progressão ponderal com dificuldades alimentares, atraso global do desenvolvimento psicomotor, dermatose eczematosa grave e hipereosinofilia (2.410-5.680/uL), investigada por Genética, Infecciologia e Doenças Metabólicas. O cariotipo revelou monossomia da região distal ao locus 1p36 – delecção 1p36. Cintigrafia com MIBG sem evidência de neuroblastoma (risco aumentado pela síndrome). O estudo metabólico foi negativo, à excepção de défice de L-carnitina, pelo que mantem suplementos estando em curso estudo molecular de CPT2 – gene associado a défice de carnitina, na localização 1p32. Quanto à hipereosinofilia, verificou-se IgE aumentada e biopsia óssea normal pelo que iniciou prednisolona 2mg/Kg/dia com resposta favorável, estando estudo molecular específico em curso. Discussão: No fenótipo da síndrome enquadram-se o atraso global do desenvolvimento, a miocardiopatia e dificuldades alimentares. A asplenia, hipereosinofilia e dermatose eczematosa graves, não associadas a esta síndrome e de etiologia ainda a esclarecer podem-se integrar eventualmente na delecção terminal do cromossoma 1. As alterações no cariotipo carecem ainda de caracterização do ponto de quebra centromérico através de array-CGH, teste com maior especificidade para avaliar a tradução clínica dos efeitos individuais e combinados dos genes envolvidos.
- Deletions within COL11A1 in Type 2 Stickler Syndrome Detected by Multiplex Ligation - Syndrome Detected by Multiplex Ligation Dependent Probe Amplification (MLPA)Publication . Vijzelaar, R; Waller, S; Errami, A; Donaldson, A; Lourenço, T; Rodrigues, M; McConnell, V; Fincham, G; Snead, M; Richards, ABackground: COL11A1 is a large complex gene around 250 kb in length and consisting of 68 exons. Pathogenic mutations in the gene can result in Stickler syndrome, Marshall syndrome or Fibrochondrogenesis. Many of the mutations resulting in either Stickler or Marshall syndrome alter splice sites and result in exon skipping, which because of the exon structure of collagen genes usually leaves the message in-frame. The mutant protein then exerts a dominant negative effect as it co-assembles with other collagen gene products. To date only one large deletion of 40 kb in the COL11A1, which was detected by RT-PCR, has been characterized. However, commonly used screening protocols, utilizing genomic amplification and exon sequencing, are unlikely to detect such large deletions. Consequently the frequency of this type of mutation is unknown. Case presentations: We have used Multiplex Ligation-Dependent Probe Amplification (MLPA) in conjunction with exon amplification and sequencing, to analyze patients with clinical features of Stickler syndrome, and have detected six novel deletions that were not found by exon sequencing alone. Conclusion: Exon deletions appear to represent a significant proportion of type 2 Stickler syndrome. This observation was previously unknown and so diagnostic screening of COL11A1 should include assays capable of detecting both large and small deletions, in addition to exon sequencing.
- Functional Study of DAND5 Variant in Patients with Congenital Heart Disease and Laterality DefectsPublication . Cristo, F; Inácio, JM; Almeida, S; Mendes, P; Martins, DS; Maio, J; Anjos, R; Belo, JAPerturbations on the Left-Right axis establishment lead to laterality defects, with frequently associated Congenital Heart Diseases (CHDs). Indeed, in the last decade, it has been reported that the etiology of isolated cases of CHDs or cases of laterality defects with associated CHDs is linked with variants of genes involved in the Nodal signaling pathway.