Síndrome de Noonan e insuficiencia aórtica severa en un paciente adulto / Noonan Syndrome and Severe Aortic Regurgitation in an Adult Patient

Introducción: El síndrome de Noonan es una enfermedad congénita con una incidencia de 1:1000-2500 recién nacidos vivos. Se encuentra subdiagnosticada en nuestro medio debido a la variabilidad clínica, lo cual no permite un adecuado control y seguimiento para detectar complicaciones consecuentes a los defectos cardiovasculares congénitos. En Perú no existen reportes de casos sobre el síndrome de Noonan y sus complicaciones. Objetivo: Discutir la importancia del examen clínico para su adecuado diagnóstico a partir de las características del síndrome de Noonan en un adulto. Caso clínico: Presentamos el caso de un varón de 33 años con síndrome de Noonan, endocarditis infecciosa e insuficiencia aórtica severa. Conclusiones: Se resalta la importancia del examen físico y el uso de criterios diagnósticos para realizar el diagnóstico del síndrome de Noonan(AU)

Introduction: Noonan syndrome is a congenital disease with an incidence of 1: 1000-2500 live newborns. Due to its clinical variability, it is underdiagnosed in our setting, which does not allow adequate control and follow-up to detect complications resulting from congenital cardiovascular defects. In Peru, there are no case reports on Noonan syndrome and its complications. Objective: To discuss the importance of clinical examination for adequate diagnosis of Noonan syndrome, based on the characteristics of the disease in an adult. Clinical case: We present the case of a 33-year-old male patient with Noonan syndrome, infective endocarditis, and severe aortic regurgitation. Conclusions: The importance of physical examination and the use of diagnostic criteria to diagnose Noonan syndrome are highlighted(AU)

Reporte de un caso de síndrome de Noonan diagnosticado en atención primaria / A case report of Noonan syndrome diagnosed in primary healthcare

El síndrome de Noonan es un trastorno genético de herencia autosómica dominante, de expresión fenotípica variable. Pertenece al grupo de las enfermedades conocidas como rasopatías, trastornos producido por las mutaciones en los genes RAS. Los pacientes desarrollan síntomas como dismorfismo facial, talla baja, enfermedad cardíaca congénita, alteraciones músculos esqueléticas y discapacidad intelectual. En el presente reporte, se describe un caso de diagnóstico del síndrome de Noonan en un paciente de 14 años, realizado a nivel de atención primaria en Ecuador. El síndrome se identificó mediante diagnóstico clínico, permitiendo su derivación al segundo y tercer nivel de salud para una atención especializada.

Noonan syndrome is an autosomal dominant inherited disorder with variable phenotypic expression. It belongs to the group of diseases known as RASopathies, which are characterized by mutations in the RAS genes. Patients develop symptoms such as facial dysmorphism, short stature, congenital heart disease, musculoskeletal disorders and mental retardation. In this article, we report a case of Noonan syndrome in a 14-year-old patient, diagnosed in a primary health center in Ecuador. The syndrome was identified through clinical diagnosis, after which the patient was referred to the secondary and tertiary levels for specialized care.

Síndrome de Noonan / Noonan syndrome

Se presenta un caso de Síndrome de Noonan, enfermedad genética poco frecuente con manifestaciones clínicas diversas, con una característica afectación cardiovascular como es la estenosis valvular pulmonar. La paciente ingresa en insuficiencia cardiaca y durante la observación se detectan datos clínicos típicamente descritos en la enfermedad, tales como talla baja, hipertelorismo, pterigium coli y tórax carinatum. Se evalúa de manera conjunta con genética y se identifican los criterios diagnósticos. La paciente es compensada y egresada por mejoría

A case of Noonan´s Syndrome, is reported here. This is a rare genetic disease with diverse clinical manifestations, with a characteristic cardiovascular involvement of pulmonary valve stenosis. The patient was admitted with heart failure. Typical clinical features were found such as short stature, hypertelorism, pterygium coli and thorax carinatum. The patient was evaluated with the genetic specialists and diagnostic criteria were identified

Tegumentary manifestations of Noonan and Noonan-related syndromes

OBJECTIVES: Noonan and Noonan-related syndromes are common autosomal dominant disorders with neuro-cardio-facial-cutaneous and developmental involvement. The objective of this article is to describe the most relevant tegumentary findings in a cohort of 41 patients with Noonan or Noonan-related syndromes and to detail certain aspects of the molecular mechanisms underlying ectodermal involvement. METHODS: A standard questionnaire was administered. A focused physical examination and a systematic review of clinical records was performed on all patients to verify the presence of tegumentary alterations. The molecular analysis of this cohort included sequencing of the following genes in all patients: PTPN1, SOS1, RAF1, KRAS, SHOC2 and BRAF. RESULTS: The most frequent tegumentary alterations were xeroderma (46%), photosensitivity (29%), excessive hair loss (24%), recurrent oral ulcers (22%), curly hair (20%), nevi (17%), markedly increased palmar and plantar creases (12%), follicular hyperkeratosis (12%), palmoplantar hyperkeratosis (10%), café-au-lait spots (10%) and sparse eyebrows (7%). Patients with mutations in PTPN11 had lower frequencies of palmar and plantar creases and palmar/plantar hyperkeratosis compared with the other patients. CONCLUSIONS: We observed that patients with mutations in genes directly involved in cell proliferation kinase cascades (SOS1, BRAF, KRAS and RAF1) had a higher frequency of hyperkeratotic lesions compared with patients with mutations in genes that have a more complex interaction with and modulation of cell proliferation kinase cascades (PTPN11). .

Estudio clínico y molecular del síndrome de Noonan / Clinical and molecular study of the Noonan syndrome

El síndrome de Noonan es una entidad autosómica dominante relativamente común, clínicamente variable y genéticamente heterogénea, caracterizado por reducción del crecimiento postnatal, dismorfismo facial distintivo, alteraciones cardíacas y déficit cognitivo variable. El gen PTPN11 se encuentra localizado en el brazo largo del cromosoma 12 y es el principal responsable de los casos clínicamente diagnosticados de esta entidad. Se reporta el caso de un lactante mayor masculino, de 18 meses de edad, evaluado de forma multidisciplinaria con diagnóstico clínico y molecular de síndrome de Noonan, con la mutación en sentido errado del gen PTPN11, G503R (c.1507 G>A). Se discutieron los diversos hallazgos clínicos y las alteraciones genéticas asociadas con esta mutación.

Noonan syndrome is a relatively common autosomal dominant entity, clinically variable and genetically heterogeneous; characterized by postnatally reduced growth, distinctive facial dysmorphism, cardiac defects and variable cognitive deficits. The PTPN11 gene is located on the long arm of chromosome 12 and is primarily responsible for the clinically diagnosed cases of this entity. We report the case of a 18 month-old boy, evaluated in a multidisciplinary way, with clinic and molecular diagnosis of Noonan syndrome, with the missense mutation in PTPN11 gene, G503R (c.1507 G>A). Several clinical features and the genetic alterations associated with this mutation are discussed.

Determinantes genéticos na síndrome de Noonan e nas síndromes Noonan-like: investigação clínica e molecular / Genetic determinants in Noonan syndrome and in Noonan-like syndromes: clinical and molecular study

A síndrome de Noonan (SN) é uma doença de herança autossômica, relativamente frequente na população e que apresenta heterogeneidade genética. Caracteriza-se por dismorfismos faciais, baixa estatura, pescoço curto/alado, alterações cardíacas, deformidades esternais e criptorquia. A SN apresenta sobreposição dos achados clínicos com outras síndromes mais raras, denominadas síndromes Noonan-like (SNL): síndrome cardio-facio-cutânea (CFC), síndrome de Costello (SC), neurofibromatose-síndrome de Noonan (NFSN), síndrome de Noonan com manchas lentiginosas/síndrome de LEOPARD (SL), síndrome de Noonan-like com perda de cabelos anágenos (SNL-PCA) e síndrome de Noonan-like com leucemia mielomonocítica juvenil (SNL-LMMJ). As SN e SNL decorrem de mutações em genes pertencentes à via de sinalização RAS/MAPK alguns dos quais são protooncogenes, o que tem despertado o interesse na caracterização do risco de desenvolvimento de neoplasias nessas síndromes. Os objetivos deste estudo visam o sequencimento conjunto dos genes PTPN11, SOS1, RAF1, KRAS, SHOC2, BRAF e HRAS em pacientes com diagnóstico clínico das SN e SNL a fim de: determinar a frequência de mutação; estabelecer uma correlação genótipo-fenótipo; estabelecer um fluxograma para o estudo molecular a partir dos hotspots; e avaliar se a variabilidade fenotípica apresentada nos pacientes com SN pode ser explicada pela presença de mutações em mais de um gene da via RAS/MAPK. Foram avaliados 194 probandos - 152 com SN e 42 com SNL (19 CFC, 15 NFNS, 4 CS e 4 LS). Mutações foram identificadas em 99 pacientes 80 com SN (53%); 19 com SNL. Apenas um paciente com SN apresentou mutação em dois genes da via RAS/MAPK (PTPN11 e SOS1). O estudo molecular na SN mostrou, assim como na literatura, um maior envolvimento do gene PTPN11 (34%), seguido dos genes SOS1 (12%) e RAF1 (7%). A comparação dos achados clínicos, levando em consideração as alterações gênicas, também confirma as correlações já descritas na literatura; entre elas...

Noonan syndrome (NS) is a relatively common, autosomal dominant disease that presents a marked genetic heterogeneity. It is characterized by facial dysmorphisms, short stature, webbed/short neck, cardiac abnormalities, esternal anomalies and cryptorchidism. NS shows clinical overlap of some of its findings with other rarer syndromes, known as Noonan-like syndromes (NLS): cardio-facio-cutaneous syndrome (CFC), Costello syndrome (CS), neurofibromatosis-Noonan syndrome (NFNS), Noonan syndrome with lentiginous stains/LEOPARD syndrome (LS), Noonan-like syndrome with loose anagen hair (NLS-LAH) and Noonan-like syndrome with juvenile myelomonocytic leukemia (NLS-JMML). NS and NLS are related to mutations in genes belonging of RAS-MAPK signaling pathway. Some of these genes are classified as proto-oncogenes. This fact also arouses the interest in the characterization of the risk for cancer development in this group of patients. The objectives of this study are to sequence the genes associated with NS and NLS (PTPN11, SOS1, RAF1, KRAS, SHOC2, HRAS and BRAF) in patients that fulfilled clinical diagnostic criteria for NS or NLS to: determine the frequency of the mutations; establish a genotype-phenotype correlation; estabilish a flowchart for molecular study from the hotspots; and evaluate when the phenotypic variability presented in NS patients can be explained by the presence of mutations in more than one gene of the RAS/MAPK pathway. This study evaluated 194 probands 152 with NS e 42 with NLS (19 CFC, 15 NFSN, 4 SC e 4 SL). Mutations were identified in 99 patients 80 with NS (53%), 19 with NLS. Only one patient presented mutation in two different genes of the RAS/MAPK pathway (PTPN11 and SOS1). The molecular analysis showed a predominance of mutations in the PTPN11 gene (34%), followed by the SOS1 (12%) and RAF1 (7%) genes in patients with NS, in accordance with the literature. Patients with NS and mutation in the: PTPN11 gene, presented a higher frequency of...

Avaliação do padrão de crescimento na síndrome de Noonan em pacientes com mutações identificadas nos genes PTPN11, SOS1, RAF1 e KRAS / Growth pattern of patients with Noonan syndrome with identified mutations in PTPN11, SOS1, RAF1 e KRAS genes

A Síndrome de Noonan (SN) é caracterizada por baixa estatura proporcionada de início pós-natal, dismorfismos faciais, cardiopatia congênita e deformidade torácica. A frequência da SN é estimada entre 1:1000 e 1:2500 nascidos vivos, com distribuição semelhante em ambos os sexos. A herança é autossômica dominante com penetrância completa, porém a maioria dos casos é esporádica. Até o momento, mutações em genes da via RAS-MAPK (PTPN11, KRAS, SOS1, RAF1, MEK1, NRAS e SHOC2) foram identificadas em aproximadamente 70% dos pacientes. Uma das principais características fenotípicas da SN é a baixa estatura pós-natal, embora o mecanismo fisiopatológico do déficit de crescimento nesta síndrome ainda não esteja totalmente esclarecido. Estudos que avaliaram o padrão de crescimento linear em crianças com SN foram realizados anteriormente ao conhecimento do diagnóstico molecular dessa síndrome. No presente estudo, avaliamos a frequência de mutação nos genes PTPN11, SOS1, RAF1 e KRAS em 152 pacientes com SN e o padrão de crescimento linear (altura) e ponderal [índice de massa corpórea (IMC)] dos pacientes com mutação identificada. No total, mutações nos genes relacionados foram encontradas em 99 pacientes (65%) do nosso estudo, com predominância do gene PTPN11 (47%), seguido do SOS1 (9%), RAF1 (7%) e KRAS (3%). Foram construídas curvas específicas para SN de Altura e IMC para idade e sexo utilizando o método LMS. Os pacientes com SN apresentaram crescimento pré-natal preservado, porém o comprometimento do crescimento pós-natal foi observado desde o primeiro ano de vida, atingindo uma altura final de -2,5 e -2,2 desvios-padrão da média para população brasileira em homens e mulheres, respectivamente. O prejuízo da altura foi maior nos pacientes com mutação no gene RAF1 em comparação com os genes PTPN11 e SOS1. O IMC dos pacientes com SN apresentou queda de 1 desvio-padrão em relação à média da população brasileira normal. O comprometimento do IMC foi menor...

Noonan Syndrome (NS) is characterized by distinctive facial features, short stature and congenital heart defects. The estimated prevalence is 1:1000 to 1:2500 live births, affecting equally both sexes. It is an autosomal dominant disorder with complete penetrance, but most cases are sporadic. To date, mutations in the RAS/MAPK pathway genes (PTPN11, KRAS, SOS1, RAF1, MEK1, NRAS and SHOC2) were identified in approximately 70% of patients. One of the cardinal signs of NS is proportional postnatal short stature although the physiopathological mechanism of growth impairment remains unclear. The current knowledge about the natural history of growth associated with NS was described before molecular diagnosis era. In this study, we performed PTPN11, SOS1, RAF1, and KRAS mutation analysis in a cohort of 152 NS patients and studied the natural linear (height) and ponderal growth [body mass index (BMI)] of NS patients with related mutations. Mutations in NS-causative genes were found in 99 patients (65%) of our cohort. The most common mutated gene was PTPN11 (47%), followed by SOS1 (9%), RAF1 (7%) and KRAS (3%). Sex-specific percentile curves for height and BMI were constructed using the LMS method. NS patients had birth weight and length within normal ranges but the postnatal growth impairment was observed during the first year of life, reaching a final height of -2.3 and -2.2 standard deviations from the mean for Brazilian healthy men and women, respectively. Postnatal growth impairment was higher in RAF1 mutation patients than in patients with SOS1 and PTPN11 mutations. BMI values in NS patients were lower in comparison with normal Brazilian population. BMI values were higher in patients with RAF1 mutations than in patients with other genotypes. Patients with mutations in PTPN11 and SOS1 genes were more likely to have pulmonary valve stenosis, whereas hypertrophic cardiomyopathy was more common in patients with mutations in the gene RAF1...

Co-occurring PTPN11 and SOS1 gene mutations in Noonan syndrome: does this predict a more severe phenotype? / Coocorrência de mutações nos genes PTPN11 e SOS1 na síndrome de Noonan: este achado prediz um fenótipo mais grave?

Noonan syndrome (NS) is an autosomal dominant disorder, with variable phenotypic expression, characterized by short stature, facial dysmorphisms and heart disease. Different genes of the RAS/MAPK signaling pathway are responsible for the syndrome, the most common are: PTPN11, SOS1, RAF1, and KRAS. The objective of this study was to report a patient with Noonan syndrome presenting mutations in two genes of RAS/MAPK pathway in order to establish whether these mutations lead to a more severe expression of the phenotype. We used direct sequencing of the PTPN11, SOS1, RAF1, and KRAS genes. We have identified two described mutations in heterozygosity: p.N308D and p.R552G in the genes PTPN11 and SOS1, respectively. The patient has typical clinical features similar to the ones with NS and mutation in only one gene, even those with the same mutation identified in this patient. A more severe or atypical phenotype was not observed, suggesting that these mutations do not exhibit an additive effect.

A síndrome de Noonan (SN) é uma doença gênica autossômica dominante, com expressão clínica variável, caracterizada por baixa estatura, dismorfismos faciais e cardiopatia. Diferentes genes da via de sinalização RAS/MAPK são responsáveis pela síndrome, sendo as mais frequentes: PTPN11, SOS1, RAF1 e KRAS. O objetivo deste estudo foi relatar um paciente com SN que apresenta mutações em dois genes da via RAS/MAPK a fim de estabelecer se essas mutações levam a uma expressão mais grave do fenótipo. Utilizou-se sequenciamento direto dos genes PTPN11, SOS1, RAF1 e KRAS. Foram identificadas duas mutações em heterozigose previamente descritas: p.N308D e p.R552G nos genes PTPN11 e SOS1, respectivamente. A paciente apresenta quadro clínico típico semelhante ao dos pacientes com SN e mutação em um único gene, mesmo naqueles com a mesma mutação identificada na paciente. Não foi observado um fenótipo mais grave ou atípico na paciente, sugerindo que as mutações não apresentam um efeito aditivo.

Síndrome de Noonan: presentación de dos casos / Noonan's syndrome: presentation of two cases

Se presentan las características oftalmológicas y clínicas de dos pacientes hermanos (hembra y varón) con diagnóstico del síndrome de Noonan. Este es un trastorno genético que produce desarrollo anormal de múltiples partes del cuerpo. Se caracteriza por una serie de signos y particularidades físicas que pueden variar ampliamente en rango y severidad según los casos. Generalmente se transmite como un rasgo genético autosómico dominante. Los casos que presentamos se caracterizan por: estenosis valvular pulmonar, hipertelorismo, retardo mental moderado, aspecto típico de la cara con filtrum (surco vertical en el centro del labio superior), párpados gruesos, epicanto, exoftalmos y ptosis palpebral.

The ophthalmological and clinical characteristics of two sibling patients (male and female) diagnosed with Noonan´s syndrome were presented in this paper. This is a genetic disorder that causes abnormal development of many parts of the body. It is characterized by a series of signs and physical peculiarities that may widely vary in range and severity from one case to another. Generally, it is transmitted as a dominant autosomal genetic trait. The two cases had the following features: pulmonary valve stenosis, hypertelorism, moderate mental retardation, typical aspect of the individual's face with filtrum (vertical sulcus located in the center of the upper lip), thick eyelids, epicanthus, exophthalmos and palpebral ptosis.

Síndrome de Noonan: do fenótipo à terapêutica com hormônio de crescimento / Noonan syndrome: from phenotype to growth hormone therapy

A síndrome de Noonan (SN) é uma síndrome genética comum que constitui importante diagnóstico diferencial em pacientes com baixa estatura, atraso puberal ou criptorquidia. A SN apresenta grande variabilidade fenotípica e é caracterizada principalmente por dismorfismo facial, cardiopatia congênita e baixa estatura. A herança é autossômica dominante com penetrância completa. O diagnóstico é clínico, com base em critérios propostos por van der Burgt, em 1994. Recentemente, diversos genes envolvidos na via de sinalização RAS-MAPK foram identificados como causadores da SN: PTPN11, KRAS, SOS1, RAF1 e MEK1. O tratamento com hormônio de crescimento (hrGH) é proposto para corrigir a baixa estatura observada nestes pacientes. Estudos recentes apontam que pacientes com SN por mutações no gene PTPN11 apresentam pior resposta ao tratamento com hrGH quando comparado com pacientes sem mutações no PTPN11. Este artigo revisará os aspectos clínicos, moleculares e do tratamento da baixa estatura de crianças com SN com hrGH.

Noonan Syndrome (NS) is one of the most common genetic syndromes and it is an important differential diagnosis in children with short stature, delayed puberty and cryptorchidism. NS is characterized by dysmorphic facial features, congenital heart defects and short stature, but there is a great variability in phenotype. NS may occur in a pattern consistent with autosomal dominant inheritance with almost complete penetrance. The diagnosis is based on a clinical score system proposed by van der Burgt e cols. in 1994. In recent years, germline mutations in the components of RAS-MAPK (mitogen activated protein kinase) pathway have been shown to be involved in the pathogenesis of NS. Mutations in PTPN11, KRAS, SOS1, RAF1 e MEK1 can explain 60-70 percent of NS molecular cause. Growth hormone therapy is proposed to correct the short stature observed in these patients. Recent studies suggest that the presence of PTPN11 mutations in patients with NS indicates a reduced growth response to short-term hrGH treatment. In this article, it is reviewed clinical and molecular aspects of NS and hrGH treatment for short stature.

Variabilidade do fenótipo de pacientes com síndrome de Noonan com e sem mutações no gene PTPN11 / Phenotype variability in Noonan syndrome patients with and without PTPN11 mutation

INTRODUÇÃO: Aproximadamente 50 por cento dos pacientes com síndrome de Noonan (SN) apresentam mutações em heterozigose no gene PTPN11. OBJETIVO: Avaliar a freqüência de mutações no PTPN11 em pacientes com SN e analisar a correlação fenótipo-genótipo. PACIENTES: 33 pacientes com SN. MÉTODO: Extração de DNA de leucócitos periféricos e seqüenciamento dos 15 exons do PTPN11. RESULTADOS: Nove diferentes mutações missense no PTPN11, incluindo a mutação P491H, ainda não descrita, foram encontradas em 16 dos 33 pacientes. As características clínicas mais freqüentes dos pacientes com SN foram: pavilhão auricular com rotação incompleta e espessamento da helix (85 por cento), baixa estatura (79 por cento), prega cervical (77 por cento) e criptorquidismo nos meninos (60 por cento). O Z da altura foi de -2,7 ± 1,2 e o do IMC foi de -1 ± 1,4. Os pacientes com mutação no PTPN11 apresentaram maior freqüência de estenose pulmonar do que os pacientes sem mutação (38 por cento vs. 6 por cento, p< 0,05). Pacientes com ou sem mutação no PTPN11 não diferiram em relação à média do Z da altura, Z do IMC, freqüência de alterações torácicas, características faciais, criptorquidia, retardo mental, dificuldade de aprendizado, pico de GH ao teste de estímulo e Z de IGF-1 ou IGFBP-3. CONCLUSÃO: Identificamos mutações no PTPN11 em 48,5 por cento dos pacientes com SN, os quais apresentaram maior freqüência de estenose pulmonar.

INTRODUCTION: Around 50 percent of Noonan syndrome (NS) patients present heterozygous mutations in the PTPN11 gene. AIM: To evaluate the frequency of mutations in the PTPN11 in patients with NS, and perform phenotype-genotype correlation. PATIENTS: 33 NS patients (23 males). METHODS: DNA was extracted from peripheral blood leukocytes, and all 15 PTPN11 exons were directly sequenced. RESULTS: Nine different missense mutations, including the novel P491H, were found in 16 of 33 NS patients. The most frequently observed features in NS patients were posteriorly rotated ears with thick helix (85 percent), short stature (79 percent), webbed neck (77 percent) and cryptorchidism (60 percent) in boys. The mean height SDS was -2.7 ± 1.2 and BMI SDS was -1 ± 1.4. Patients with PTPN11 mutations presented a higher incidence of pulmonary stenosis than patients without mutations (38 percent vs. 6 percent, p< 0.05). Patients with and without mutations did not present differences regarding height SDS, BMI SDS, frequency of thorax deformity, facial characteristics, cryptorchidism, mental retardation, learning disabilities, GH peak at stimulation test and IGF-1 or IGFBP-3 SDS. CONCLUSION: We identified missense mutations in 48.5 percent of the NS patients. There was a positive correlation between the presence of PTPN11 mutations and pulmonary stenosis frequency in NS patients.

Estudo do gene PTPN11 nos pacientes afetados pela síndrome de Noonan / The PTPN11 gene analysis in Noonan syndrome patients

A análise do gene PTPN11 foi realizada em 50 probandos com síndrome de Noonan e 8 com síndrome de Noonan-like. Na síndrome de Noonan foram identificadas mutações missense em 42 por cento dos afetados, corroborando a heterogeneidade genética desta doença. A mutação T73I parece predispor a uma doença mieloproliferativa na síndrome de Noonan, embora uma correlação genótipo-fenótipo ainda não tenha sido estabelecida. O gene PTPN11 é o principal responsável pela síndrome de LEOPARD (3/3 pacientes com mutação) e, em parte, pelas síndromes da neurofibromatose-Noonan (1 com mutação) e Noonan-like/lesões múlitplas de células gigantes (1/3 com mutação) / A PTPN11 gene analysis was performed in 50 Noonan and 8 Noonan-like syndrome probands. Missense mutations were identified in 42 per cent of the Noonan syndrome cohort, corroborating the idea of its genetic heterogeneity. A definitive genotype-phenotype correlation was not established, but the T73I mutation seems to predispose to a myeloproliferative disorder in Noonan syndrome. The PTPN11 gene is the main one in LEOPARD syndrome (3/3 patients with the same mutation) and it plays a role in neurofibromatosis-Noonan (one patient had a PTPN11 gene mutation) and Noonan-like/multiple giant cell lesion syndromes (1/3 with a PTPN11 gene mutation)...

Estudo do gene PTPN11 em pacientes com a síndrome de Noonan e crianças com baixa estatura idiopática / Study of PTPpN11 gene in patients with Noonan syndrome and child with idiopathic short stature

A síndrome de Noonan (SN), caracterizada por baixa estatura, aspectos dismórficos e cardiopatia congênita, foi associada ao gene PTPN11. Estudamos o PTPN11 em pacientes com SN, pais de portadores de mutação e crianças com baixa estatura idiopática (BEI) que apresentam estigmas sugestivos da SN, sem critérios suficientes para o diagnóstico. Encontramos mutações missense em heterozigoze no PTPN11 em 42,3 per cent dos pacientes com SN. Não identificamos alterações nos pais de portadores de mutação no PTPN11 com fenótipo normal tampouco em crianças com BEI. A única diferença estatisticamente significante entre os grupos com e sem mutação foi a resposta em longo prazo ao hGH, melhor no grupo sem mutação / Noonan syndrome (NS), characterized by short stature, dysmorphic facial and thoracic features and congenital heart disease, was associated to PTPN11 gene. We studied the PTPN11 in patients with NS, parents of mutation-positive NS patients and idiopathic short stature children with signs related to NS without fulfilling the diagnostic criteria. We found missense mutations in 42.3 per cent of the NS group. Parents of NS mutation-positive patients did not present mutations, nor did children with short stature. The only statistically significant difference between groups with and without mutations was response to long term use of hGH, better on the mutation-negative group...

Achados cardíacos em 31 pacientes com síndrome de Noonan / Cardiac findings in 31 patients with Noonan's syndrome

OBJECTIVE: To evaluate cardiac findings in 31 Noonan syndrome patients. METHODS: Thirty-one (18 males and 13 females)patients from 26 families affected with Noonan's syndrome were evaluated from the cardiac point of view with electrocardiography and echodopplercardiography. RESULTS: Twenty patients had some type of cardiac abnormality. The most frequent was pulmonary valve stenosis followed by hypertrophic myocardiopathy, commonly associated with valve defects. Upper deviation of the QRS axis was observed in 80 percent of these patients. CONCLUSION: In view of the high frequency and diversity of cardiac abnormalities present in Noonan syndrome, cardiac evaluation with electrocardiography and echocardiography should be performed in all patients diagnostically suspected of having this disease

Noonan syndrome: a clinical and genetic study of 31 patients

Noonan syndrome is a multiple congenital anomaly syndrome, inherited in an autosomal dominant pattern. We studied 31 patients (18 males and 13 females) affected by this disorder regarding their clinical and genetic characteristics. The most frequent clinical findings were short stature (71 percent); craniofacial dysmorphisms, especially hypertelorism, ptosis, downslanting of the palpebral fissures; short or webbed neck (87 percent); cardiac anomalies (65 percent), and fetal pads in fingers and toes (70 percent). After studying the probands' first-degree relatives, we made the diagnosis of Noonan syndrome in more than one family member in three families. Therefore, the majority of our cases were sporadic

Síndrome de Noonan: Estudo clínico-genético de 30 pacientes / Noonan syndrome: clinical-genetic study of 30 patients

A síndrome de Noonan (SN), entidade genética de herança autossômica dominante, subdiagnosticada em funçäo da expressividade extremamente variável do quadro clínico, é possivelmente uma das síndromes mendelianas mais freqüentes. Em um estudo prospectivo foram avaliados 30 pacientes a partir de um protocolo de investigaçäo clínico-laboratorial. Entre os critérios clínicos descritos na SN os mais importantes para o diagnóstico foram: ptose palpebral, micrognatia, fendas anti-down, raiz nasal deprimida, base nasal larga, hipertelorismo mamilar, criptorquidia e ptergium colli. Retardo mental era presente ou questionável em 14 pacientes. Os achados laboratoriais mais freqüentes foram: cardiopatia (predominando estenose pulmonar e comunicaçäo inter-atrial), anomalias renais, atraso de idade óssea, anomalias de coluna cervical, alteraçöes oftalmológicas, alteraçöes de audiçäo e coagulograma alterado. Apenas três pacientes (10 porcento) apresentaram displasia linfática, sugerindo possivelmente uma mortalidade aumentada neste grupo. Dois pacientes têm a reconhecida associaçäo da SN com neurofibromatose. Dois casos familiais foram confirmados e há nove casos familiais suspeitos. A idade paterna avançada nos casos näo familiais seria compatível com a mutaçäo nova para gen autossômico dominante. Os dados apresentados ressaltam a importância da sistematizaçäo do protocolo de investigaçäo e acompanhamento, visando a antecipaçäo e prevençäo de complicaçöes, bem como subsídios para o aconselhamento genético