Background/purpose: The aim of this study was to compare the incidences of various associated anomalies among subjects with high and low anorectal malformation (ARM), study the coexistence of these anomalies, and compare their frequency with those quoted in the existing literature.
Methods: Ten years of data (from January 1993 through December 2002) on the 416 subjects from our center with anorectal malformations (ARM) were evaluated. The subjects with supra or translevator rectal pouch (radiologic or operative findings) were classified as high ARM and the rest as low ARM. The associated anomalies studied were vertebral, skeletal, renal, cardiac, vesicoureteric reflux (VUR), gastrointestinal, tracheoesophageal fistula, spinal, genital, and miscellaneous. For a detailed comparison, 4 subgroups were made: boys with high ARM, boys with low ARM, girls with high ARM, and girls with low ARM. Statistical methods were used for intergroup comparison.
Results: There were 68% male and 32% female subjects. Overall, 58% of subjects had high ARM (supralevator and translevator). Our attempt to compare the incidences of anomalies in our study population with those in other populations was defeated because of nonuniformity of classification and investigation of these anomalies in different studies. We found a frequent clubbing of anomalies affecting distantly developing anatomic regions in patients with ARM in many studies. The highest incidence of associated anomalies was found among boys with high ARM. The male subjects also had significantly more genital anomalies in association with low ARM and gastrointestinal tract anomalies in association with high ARM. On the other hand, girls had more urologic anomalies with high ARM and VUR with low ARM.
Conclusions: Except for a low incidence of spinal anomalies (8%) and of VUR (1.7%), the incidences of most associated anomalies in our study were comparable with those of the earlier studies. Additionally, the girls with high ARM were observed to have significantly more urologic anomalies compared with the boys with high ARM in contrast to the results of the earlier reports. The existence of anomalies in distantly developing anatomic regions in patients with ARM supports the possibility of a "generalized" insult during embryogenesis rather than a ("localized") defect. It was observed that the boys with ARM are more likely to suffer morbidity because of frequent occurrence of multiple associated anomalies, and it may be worthwhile to evaluate of the role of sex chromosome in relation to ARM. The authors are also of the view that there is a need for more uniformity in classification of the anomalies and in their diagnostic approach because various reported studies have differed so widely on these aspects that any interstudy comparison is difficult or not feasible.