Discussion
The extent and severity of trisomy 13, a common aneuploidy, depend on
the specific location of the trisomy in chromosome 13, as well as the
percentage of abnormal cells. Affected infants usually present with the
profound mental retardation, microcephaly, microphthalmia, cleft lip,
cleft palate, hypertelorism, malformed ears, abnormalities of the
central nervous system, renal malformations, congenital cardiac defects,
capillary hemangiomas (most frequently on the center of the forehead),
and limb malformation. Males may also be affected by cryptorchidism. In
addition, limb malformations, including polydactyly, flexion and
possible overlapping of fingers, and prominent heels of the feet, are
common in infants with trisomy 13 syndrome. However, Ectrodactyly, a
deformity affecting the central rays of the hands and/or feet, and
occurs as an isolated entity or as part of a syndrome, is a rare
presentation in infants with trisomy 13. Indeed, there have been only a
few reported cases.
Our patient also possessed congenital diaphragmatic hernia, another rare
finding in patients with trisomy 13. CDH is life- threatening pathology
in infants and can be a major cause of death. It can be either an
isolated anomaly or associated with other abnormalities, such as major
structural malformations, chromosomal abnormalities, and/or single gene
disorders. Severe anomalies associated with CDH may influence diagnosis,
treatment, and survival. In our patient, an antenatal scan detected left
CDH as an anomaly. Although a prenatal genetic diagnosis of trisomy
would have aided decision-making and allowed for the creation of a
treatment plan, it was not performed. Upon birth, the presence of
multiple congenital anomalies combined with CDH suggested a complex
chromosomal diagnosis, which was confirmed by postnatal karyotyping as
trisomy 13. This result deferred the decision of surgical management as
the prognosis for CDH is poor in an abnormal chromosomal microarray
case.