4.1 Lists of selected external and internal congenital anomalies to consider for monitoring
For surveillance programmes just starting out, the following are suggested as an initial list of external congenital anomalies to consider for monitoring. They were chosen because they are relatively easy to identify at birth, have significant public health impact, and, for some congenital anomalies, there is the potential for primary prevention.
- Spina bifida
- Cleft palate alone
- Cleft lip alone
- Cleft palate with cleft lip
- Talipes equinovarus
- Reduction defects of upper and lower limbs (longitudinal, transverse, and intercalary)
- Exomphalos (omphalocele)
Some countries have more diagnostic resources or more developed programmes than others. For these countries, including selected internal congenital anomalies might be of interest. The following is a list of internal congenital anomalies that are commonly collected by most major congenital anomaly surveillance programmes. Considerations for selection of these anomalies included the public health significance and opportunities for prevention and intervention.
- Common truncus (truncus arteriosus)
- Hypoplastic left heart syndrome
- Interrupted aortic arch
- Pulmonary valve atresia
- Tetralogy of Fallot
- Transposition of the great arteries
- Tricuspid valve atresia and stenosis
- Trisomy 21 (Down syndrome)
- Renal agenesis/hypoplasia
- Esophageal agenesis/hypoplasia
- Large intestinal atresia/stenosis
- Rectal atresia/stenosis
As participating facilities or hospitals and surveillance programme personnel gain experience during the development process, additional congenital anomalies such as the internal anomalies listed above (or others) can be added in a stepwise fashion, starting with those that are of special interest or concern to the country or region, and eventually could include all of the major congenital anomalies listed in Chapter XVII of the ICD-10: “Congenital malformations, deformations and chromosomal anomalies (Q00–Q99)”. However, high-quality data on a smaller number of congenital anomalies will be more useful for public health than poor-quality data on all congenital anomalies.
The list of congenital anomalies included in this manual is not exhaustive. Programmes interested in more detailed information on the inclusion of additional defects or in prenatal diagnosis in congenital anomalies surveillance programmes can find some useful and practical suggestions and tips in the guidelines developed by the NBDPN in the USA.
The decision on selecting which defects to include in a surveillance programme should be evaluated based on available resources. If the fetus or neonate has at least one eligible congenital anomaly, this and any other observable major and minor congenital anomalies are described in detail and included on the abstraction form (see Appendix G pdf icon[233 KB, 2 Pages]).
When coding the congenital anomalies, it is important to be as specific as possible and to avoid using codes that are nonspecific or too general. Please refer to Chapter 6 for more information about coding.