PhotoQuiz 71

Please submit your response to this link: https://forms.gle/RsDw5jYGLYzC8u7v9 A 9-year-old male child, born to second-degree consanguineous parents, presented with recurrent fractures from infancy, short stature (−6.8 standard deviation [SD]), microcephaly (−4.8 SD), joint hyperextensibility, and bilateral eye abnormality with visual deficit. Radiographs of the long bones are given below. Identify the condition.Answer to PhotoQuiz 70 Pallister–Killian syndrome: mos47,XY,i(12)(p10)[29]/46,XY[21] (OMIM: # 601803) Pallister–Killian syndrome (PKS) is a rare, typically sporadic, multisystem developmental disorder caused by mosaic tetrasomy of the short arm of chromosome 12 (isochromosome 12p, i (12p)). PKS most commonly presents in the neonatal or early infantile period. Affected individuals usually have severe hypotonia (umbilical hernia), global developmental delay, and intellectual disability. Characteristic facial dysmorphism includes a high forehead, sparse frontotemporal hair, hypertelorism, flat nasal bridge, and a long philtrum. Additional features include hearing loss, visual impairment, seizures, cardiac malformations, diaphragmatic hernia, supernumerary nipples, and skin pigmentation anomalies (mottling or hypo-/hyperpigmented streaks). Standard karyotyping from peripheral blood may be normal; thus, skin fibroblast analysis and buccal smears are more sensitive for detecting the isochromosome 12p.