Prenatal features of Noonan syndrome

Targeted ultrasound examination and DNA testing for Noonan syndrome, in fetuses with increased nuchal translucency and normal karyotype

“…In the presented cases we show that suspicion of Noonan syndrome should arise when, after an increased NT, ultrasound investigation in the second trimester shows a persistant NF or cystic hygroma in combination with at least one of the following features: hydrops fetalis, pleural effusion, cardiac anomalies, polyhydramnios or specific facial abnormalities (Table 1) (Witt et al, 1987;Benacerraf et al, 1989;Izquierdo et al, 1990;Sonesson et al, 1992;Nisbet et al, 1999;Achiron et al, 2000;Bradley et al, 2001;Menashe et al, 2002;Witters et al, 2002;Eccles et al, 2003;Gandhi et al, 2004;Ragavan et al, 2005;Schluter et al, 2005;Becker et al, 2007;Bekker et al, 2007;Kiyota et al, 2008;Gonzalez-Huerta et al, 2010;Houweling et al, 2010). Heart anomalies are found in 60-70% of the postnatal cases (mostly pulmonary stenosis, ASDS and hypertrophic obstructive cardiomyopathy) and will be one of the major causes requiring medical attention (Sharland et al, 1992;Allanson, 1993).…”

“…As above-mentioned findings are mild and not specific, being common to other syndromes and sometimes also present in normal fetuses it is necessary to define which sonographic findings should prompt targeted prenatal DNA diagnostics for Noonan syndrome (Nisbet et al, 1999;Schluter et al, 2005). Houweling et al (2010) advocate that given the high incidence of Noonan syndrome in fetuses with increased NT and normal karyotype, genetic counseling and Noonan syndrome mutation detection should always be offered, even in the absence of additional abnormalities.…”

“…NT, nuchal translucency; JLS, jugular lymphatic sacs. a Witt et al (1987), Benacerraf et al (1989), Izquierdo et al (1990), Sonesson et al (1992), Nisbet et al (1999), Achiron et al (2000), Bradley et al (2001), Menashe et al (2002), Witters et al (2002), Eccles et al (2003), Gandhi et al (2004) …”

Prenatal diagnostic testing of the Noonan syndrome genes in fetuses with abnormal ultrasound findings

“…[17][18][19] Prenatal features of NS are increased nuchal translucency (NT), distended jugular lymphatic sacs (JLS), cystic hygroma, hydrops fetalis, pleural effusion, polyhydramnios, CHD and renal abnormalities. [20][21][22][23][24] The first prenatal DNA diagnosis of NS in a fetus with massive cystic hygroma, pleural effusion and ascites showed a mutation in the PTPN11 gene. 25 Lee et al 26 performed a retrospective review of prenatal PTPN11 testing.…”

The cardiofaciocutaneous syndrome: prenatal findings in two patients

“…Prenatal pleural effusion and hydrops are severe manifestations of lymphatic vessel dysplasia, and polyhydramnios is present in two-thirds of prenatally diagnosed cases (Nisbet et al, 1999;The Fetal Medicine Foundation, 2007). A short femur and renal pelvic dilatation are other described prenatal features in Noonan syndrome (Nisbet et al, 1999).…”