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Okamoto syndrome in a girl of Caucasian origin
Margharita Markouri1, Themistokles Karpathios, Argirios Dinopoulos
1Department of Paediatrics, Athens Medical Centre, Athens, Greece. markour@hol.gr
Abstract:
We report the clinical and genetic evaluation of a 2-year-old Greek female with striking phenotypic similarities to the three previously published cases of Okamoto syndrome. The main features were characteristic facies, cleft palate, generalized hypotonia, severe developmental delay, congenital hydronephrosis, and congenital heart defects. Routine chromosome testing and whole-genome high-resolution comparative genetic hybridization analysis were negative for any gross numerical or structural chromosome aberrations and for microdeletions/duplications of more than 3 million base pairs respectively. Fluorescence in situ hybridization analysis for 22q11.2 deletion and DNA analysis of the protein tyrosine phosphatase, non-receptor type II gene were normal, thus excluding DiGeorge and Noonan syndromes. Our patient did not show most of the cardinal features of Schinzel-Giedion, otopalatodigital, and C-trigonocephaly syndromes. Moreover, in our patient some new malformations were identified: unilateral kidney hypoplasia and severe anal stenosis. The latter was considered as pertinent and is described here to establish a wider clinical spectrum of Okamoto syndrome. At the age of 3 years 6 months the child continues to show severe growth failure and significant global developmental delay. For the practising paediatrician it is prudent to bear Okamoto syndrome in mind, especially in children with learning disability and a pattern of dysmorphic features.
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