825 Trisomy 13 with Anorectal Malformation:An Association or An Incidental Finding

Abstract

This report describes an infant with trisomy 13 associated with imperforate anus. Clinical features of patau syndrome described in standard texts do not include imperforate anus or anorectal malformations (ARM). In our search of the English literature only four cases of trisomy13 have being associated with imperforate anus: a de novo mosaicism 46, XX, t(13q13q)/46, XX,-13,+r(13), a partial trisomy of chromosome 13q and 20p and trisomy 13 with Robertsonian translocation of extra chromosome 13 to chromosome 14. The fourth case of trisomy 13 has been mentioned by Cho et al in 2001 in which the form of trisomy has not been described. This baby girl was born at term by emergency caesarian section for fetal tachycardia to non consanguineous parents. On initial examination the she was noted to have overlapping fingers, widely spacednipples, ulnar deviation of hands, microphthalmia with ectropion of the right eye. Systemic examination revealed imperforate anus and a systolic murmur. The baby was transferred to a surgical unit and had a colostomy on day one of life under general anaesthesia. She was discharged home on day 21 of life. Out of the four cases of trisomy 13 described so far with imperforate anus all have been either mosaics or translocations. Our baby is unique as she is possibly the only reported child with Patau syndrome 47 XX + 13 (pure non disjunction and not mosaic/ translocation) to have anorectal malformation. It is still questionable whether imperforate anus is a true association of trisomy 13 or just a co-incidental occurence.