Child with Deletion 9p Syndrome Presenting with Craniofacial Dysmorphism, Developmental Delay, and Multiple Congenital Malformations

A 4-month-old Sri Lankan male child case with a de novo terminal deletion in the p22 pter region of chromosome 9 is described. The child presented with craniofacial dysmorphism, developmental delay, and congenital malformations in agreement with the consensus phenotype. A distinctive feature observed in this child was complete collapse of the left lung due to malformation of lung tissue. Cytogenetic studies confirmed terminal deletion of the short arm of chromosome 9 distal to band p22 [46,XY,del(9)(p22 pter)]. This is the first reported case of a de novo deletion 9p syndrome associated with pulmonary hypoplasia. This finding contributes to the widening of the spectrum of phenotypic features associated with deletion 9p syndrome. 1. Introduction Deletion 9p syndrome is a rare structural chromosomal disorder characterized by craniofacial dysmorphism, various congenital malformations, and psychomotor delay. The consensus phenotype consists of trigonocephaly with prominent forehead, small palpebral fissures, flat nasal bridge, low-set dysplastic ears, anteverted nostrils, long philtrum, and disproportionately long phalanges [1]. Congenital malformations include cardiac defects, inguinal hernia, omphalocele, and abnormal external genitalia [2]. These features are known to be characteristically associated with deletion 9p syndrome, and knowledge of these associations aids in the early clinical recognition and cytogenetic diagnosis of this syndrome [3]. The breakpoints usually occur in bands from 9p22 to 24, and most patients have either pure terminal deletions involving 9p or unbalanced chromosomal rearrangements involving chromosome 9p and another chromosome. The deletion is de novo (sporadic) in two-thirds of cases arising during either paternal or maternal meiosis and familial in the remaining one-third arising from unbalanced chromosome rearrangements inherited from a parent with a balanced translocation [1, 4]. The first case was reported by Alfi et al. in 1973, and since then, more than 150 cases have so far been reported worldwide [1, 3]. This paper describes the first reported case of a de novo deletion 9p syndrome associated with pulmonary hypoplasia. 2. Case Presentation A 4-month-old Sri Lankan male child with dysmorphic features and congenital malformations was referred with a clinical suspicion of Down syndrome to our centre for chromosomal analysis and genetic counseling. He was the first child born to healthy, nonconsanguineous parents. Family history was unremarkable. The father was aged 35 years and the mother 30 years at the time of baby’s