Molecular and phenotypic characterization of ring chromosome 22 in two unrelated patients.

We report on the cytogenetic and molecular characterization of a constitutional de novo ring chromosome 22 (r(22)) in 2 unrelated patients with emphasis on different hypotheses proposed to explain the phenotypic variability characterizing this genomic disorder. In both patients, molecular investigations using FISH and array-CGH techniques revealed a 22q terminal deletion involving the 22q13.33 critical region. The size of the deletion was estimated to at least 1.35 Mb in the first proband and to only 300 kb in the second. They both exhibited the major features of r(22) syndrome, but the first patient was more profoundly affected. He had a more severe phenotype, further complicated by behavioral anomalies, autistic-like features with abnormal EEG pattern and brain MRI profile. Haploinsufficiency of the SHANK3 gene, lying in the minimal critical region, is nowadays considered as responsible for most neurobehavioral anomalies. Nevertheless, phenotypic severity and occurrence of additional features in the first patient suggest a potential involvement of one or more specific gene(s) located proximally to SHANK3 (as PLXNB2, PANX2, ALG12 or MLC1), acting either independently of it or by regulating or promoting its expression and thus disrupting its function when deleted.

[Pseudohypoparathyroidism revealed by Fahr syndrome]. / Un syndrome de Fahr révélateur d'une pseudohypoparathyroïdie.

Fahr syndrome is defined by the presence of striopallidal notched bilateral and symmetric calcifications at the base of the skull. We report an observation of a 12-year-old girl who presented gait impairment, seizures, somnolence and aphasia. Brain computed tomodensitometry identified intracranial calcifications. The tests demonstrated pseudohypoparathyroidism.

[Fetus in fetu: a case report]. / Foetus in foetu : à propos d'un cas.

Fetus in fetu is an abnormality secondary to abnormal embryogenesis in a diamniotic, monochorionic pregnancy. It is a rare pathological condition and fewer than 100 cases have been reported in the literature. We report a neonatal case which occurred in a girl who had been hospitalized since birth because of an abdominal mass. A conventional radiograph of the abdomen revealed a right mass containing calcifications, which displaced intestinal structures to the left. Abdominal ultrasonography and CT scan revealed a vascular and heterogeneous mass that contained numerous calcifications. The diagnosis of teratoma was suspected. After surgical excision, macroscopic and pathologic examination confirmed the diagnosis of FIF.

[Esophageal cervical duplication revealed by stridor: a case report]. / Stridor révélateur d'une duplication oesophagienne cervicale : à propos d'un cas.

Esophageal duplications are rare malformations. They account for 15 to 20% of esophageal malformations. Duplications are cystic or, rarely, tubular. The location is thoracic in 95% of the cases. The clinical manifestations are mostly related to compression of the neighboring organs. Treatment is surgical. We report a case of esophageal duplication in a 22-month-old child; the major symptom was congenital stridor. The diagnosis of esophageal duplication was suspected at the chest computed tomography imaging study and confirmed after excision and pathologic examination.