The King Abdullah Specialist Children's Hospital (KASCH) classification of anatomical gastrointestinal tract (GI) anomalies in conjoined twins.

BACKGROUND

The aim of this study is to characterize the anatomical gastrointestinal (GI) tract anomalies observed in conjoined twins and to classify the various forms of those anomalies encountered throughout our experience into a well-formed classification system.

METHODS

This is a retrospective chart-review study to evaluate the anatomical gastrointestinal tract anomalies in conjoined twins that were evaluated or received medical care at our center using data obtained from patients' medical records.

RESULT: Between 1990 and 2025, we evaluated 149 sets of conjoined twins where 63 sets of conjoined twins were successfully separated. The reason for nonseparation in the other 86 was the presence of: a single heart, majorly communicating hearts, or major chromosomal anomalies. 25 sets of conjoined twins found to have anatomical gastrointestinal tract anomalies. Four distinct patterns were characterized. The most common type of anatomical gastrointestinal tract anomalies was found to be the third pattern which is shared distal ileum and colon, observed in 16 sets of conjoined twins in our series.

CONCLUSION

In our experience, the type of anatomical gastrointestinal tract anomaly has never been a reason for nonseparation in our case series. The classification system is based on the anatomical location of fusion and the extent of the fusion as well. Identifying the exact pattern of anatomical gastrointestinal tract anomaly is a crucial step to ensure proper surgical technique selection.