5.5 Coding Multiple Congenital Anomalies
Approximately 75% of babies with a major congenital anomaly present as isolated anomalies, and the remaining 25% have more than one major anomaly (35, 36). More details about the types of congenital anomalies according to clinical presentation are presented in Appendix C.
When more than one congenital anomaly is present, a detailed description of each major anomaly is recorded. Congenital anomalies surveillance programmes vary regarding the number of codes they record for a fetus or neonate, but allowing coding for at least 10 anomalies should be sufficient. Major anomalies are given priority over any minor anomalies for being captured within the available 10 (or more) diagnoses recorded.
Certain syndromes can also be coded according to the ICD-10 classification (12). When the ICD-10 code is not specific enough (e.g. codes listed in the group Q87 – “Other specified congenital malformation syndromes affecting multiple systems”), then using the classification developed by the RCPCH could be beneficial (34). Regardless of which classification(s) is used, a thorough description of any observed anomaly is very important for accurate coding of congenital anomalies.