Spectrum of anorectal anomalies in pygopagus twins.
OBJECTIVE
The literature lacks a concise description of the anorectal anomalies encountered in pygopagus twins.


METHODS
This is a retrospective literature review of 34 pygopagus twins highlighting their anorectal malformations.


RESULTS
Overall pygopagus twins represent 17% of all conjoined twins. Live-birth pygopagus twins are more commonly female (86%), whereas stillborns are commonly male (80%). Half of the twins had nonfused rectums, and half had fused rectums. The nonfused had 2 rectums (80%) or one rectum and one rectovaginal fistula (20%). The fused had high (46%) or low (54%) rectal junctions. All reported living male pygopagus twins have had nonfused rectums. All can be managed applying the principles of posterior sagittal anorectoplasty.


CONCLUSIONS
In general, live-born male pygopagus twins are likely to survive with a nonfused rectum and good bowel function, whereas live-born female pygopagus twins have a good chance of surviving with a fused rectum (high or low), which requires appropriate operative reconstruction.
Janik
Joseph S
JS
Department of Pediatric Surgery, The Children's Hospital/University of Colorado Health Sciences Center, Denver, CO 80218, USA.
Hendrickson
Richard J
RJ
Janik
Joseph P
JP
Bensard
Denis D
DD
Partrick
David A
DA
Karrer
Frederick M
FM
D000015:Abnormalities, Multiple / Q000453:epidemiology* / Q000401:mortality / Q000601:surgery; D001003:Anal Canal / Q000002:abnormalities* / Q000601:surgery; D004200:Diseases in Twins / Q000453:epidemiology*; D005260:Female; D005313:Fetal Death / Q000453:epidemiology; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D012006:Rectovaginal Fistula / Q000209:etiology; D012007:Rectum / Q000002:abnormalities* / Q000601:surgery; D012189:Retrospective Studies; D012737:Sex Factors; D013131:Spine / Q000002:abnormalities; D016019:Survival Analysis; D014428:Twins, Conjoined / Q000473:pathology*; D014621:Vagina / Q000002:abnormalities / Q000601:surgery