PARTIAL TRISOMY 3p24.3 AND PARTIAL MONOSOMY 5p15.33: CASE REPORT AND A LITERATURE REVIEW

Summary: Partial trisomy 3p 24.3 and partial monosomy 5p15.33: case report and a literature review: We report on a preterm neonate with a deletion of the distal short arm of chromosome 5pl 5.33 and partial trisomy of the distal short arm of chromosome 3p24.3. The patient was the first-born monozygotic twin. There were no pertinent facial or physical features except a small lower lip hemangioma.The neonate presented with cardiac defects, which included a patent ductus arteriosus, an atrial septal defect and ventricular septal defects. After 94 days of age, however, the patient died from superior vena cava syndrome, recurrent chylothoraces and generalized anasarca. Array comparative genomic hybridization (aCGH) using a custom oligonucleotide microarray (Agilent 180,000 probe platform revealed a terminal duplication of 1,128 oligonucleotide probes from 3pter to 3p24.3, spanning approximately 20.4 megabases (Mb), and a terminal deletion of 271 oligonucleotide probes from 5pter to 5pl5.33, spanning approximately 4.3 Mb. This is the first report of a patient with partial trisomy 3p24.3 and partial monosomy 5p 15.33 without major dysmorphic features.Key-words: Partial trisomy 3p - Partial monosomy 5p - Deletion of chromosome - CGH microarray.INTRODUCTIONPartial trisomy 3p or trisomy 3p syndrome is rare. It is characterized by non-specific craniofacial features. Congenital heart disease is the presenting feature of trisomy 3p syndrome, and the other more common clinical features are psychomotor and mental retardation (1, 12, 15). However, there have been two case reports on trisomy 3 ? syndrome that lacked major dysmorphic signs (14). The clinical feature of the monosomy 5p (cri-du-chat syndrome) are well known. The phenotypes of the syndrome in young children include microcephaly, hypertelorism, micrognathia, low set ears, epicanthal folds, hypotonia and severe psychomotor and mental retardation (2, 7). The most characteristic feature in newborns is a high pitched cat-like cry (2) which often makes it difficult to diagnose in the newborns period when it is not present. We report a case of partial trisomy 3p with monosomy 5p and review the literature.To our knowledge, our case is the first to describe a neonate with partial deletion of the short arm of chromosome 5 and a partial trisomy of the short arm of chromosome 3 with absence of major dysmorphic features.CLINICAL REPORTA 1,165-g female monozygotic twin A infant was delivered at 28 weeks' gestation to a 31 -year-old G4P1123 Hispanic mother by cesarean section due to preterm labor, twin pregnancy and breech presentation. Apgar scores were 5 and 8 at 1 and 5 minutes respectively. The pregnancy was uncomplicated. The mother had 2 miscarriages prior to this pregnancy. No genetic studies were performed during these past pregnancies. Her first child from a previous marriage, a 12 years old girl, appeared normal.Physical examination revealed a weight of 1,165-g (25th centile) length 35 cm (10th centile), head circumference 27 cm (50th centile). The physical exam was unremarkable for dysmorphic features except lower lip hemangioma. She received surfactant for respiratory distress syndrome and was on a mechanical ventilator since birth.Echocardiogram on the 14th day of life showed a large patent ductus arteriosus (PDA), a small atrial (secundum) septal defect (ASD) and two small muscular ventricular septal defects (VSDs). She subsequently underwent PDA ligation on the 22nd day of life because of congestive heart failure. A Broviac catheter was placed into the right external jugular vein on the 15th day of life for intravenous hyperalimentation. She developed staphylococcal sepsis and chylothoraces secondary to superior vena cava obstruction on the 39th and 41s' day of life respectively.She required placement of multiple chest tubes to drain the chylothoraces. However, she did not improve despite vigorous intervention and gradually developed generalized anasarca and multiple organ failure. …