Abstract：
18p deletion (18p-) syndrome is a rare chromosome abnormality that has a wide range of phenotypes, with short stature, intellectual disability, and facial dysmorphism being the main clinical features. Here, we report the first case in Korea of a 16-year-old male adolescent with 18p- syndrome resulting from de novo unbalanced whole-arm translocation between chromosomes 13 and 18 (45, XY, der(13;18)(q10:q10)). Three rare clinical findings were discovered that had not been reported in the previous literature; morbid obesity without other hormonal disturbances, rib cage deformity leading to the direct compression of the liver, and lumbar spondylolisthesis at the L5-S1 level. This case expands the phenotypic spectrum of 18p- syndrome and highlights the importance of considering chromosomal analysis, since this syndrome can be easily overlooked in a clinical setting, especially without distinctive symptoms of other organs, due to its nonspecific but typical features of short stature and mild intellectual disability with a mildly dysmorphic face. Moreover, since not all cases of 18p- syndrome with unbalanced translocation (13;18) show the same phenotype, multidisciplinary examinations and follow-up seem to be important to monitor evolving and developing clinical manifestations and to predict prognosis in advance associated with the specific genes of 18p breakpoint regions.
摘要：
18p缺失（18p-）综合征是一种罕见的染色体异常，具有广泛的表型，身材矮小，智力残疾,面部畸形是主要的临床特征。这里,我们报告了韩国首例16岁的男性青少年18p综合征，该综合征是由染色体13和18之间的从头不平衡的全臂易位引起的（45，XY，der（13；18）（q10：q10））。发现了三个罕见的临床发现，在以前的文献中没有报道过；病态肥胖没有其他激素紊乱，肋骨畸形导致肝脏直接压迫，L5-S1水平的腰椎滑脱。此病例扩展了18p综合征的表型谱，突出了考虑染色体分析的重要性，因为这种综合征在临床上很容易被忽视，尤其是没有其他器官的明显症状，由于其非特异性但典型的身材矮小和轻度智力残疾，面部轻度畸形。此外，因为不是所有的18p-综合征与不平衡易位（13;18）显示相同的表型，多学科检查和随访对于监测发展和发展中的临床表现以及提前预测与18p断点区域的特定基因相关的预后似乎很重要。
