Congenital anomalies encompass a range of abnormalities affecting the structure and or function of different organs. These abnormalities can be caused by genetic changes, environmental factors, and or teratogenic exposures. Anomalies can be classified as malformations, deformations, disruptions, or dysplasias.
Malformations are defects where a structure is either abnormally formed, partially formed, or is not formed at all. They can be major. meaning they often have medical consequences and require surgical repair, or minor, in which case the consequence is mostly cosmetic.
Deformation is the abnormal modification of a normally forming structure, usually due to intrauterine factors, such as decreased amniotic fluid. Disruptions are defects that occur due to vascular or mechanical processes, causing tissue compromise and otherwise normally developing structure. Dysplasias are tissue malformations due to intrinsic abnormalities at the level of cellular organization. Congenital anomalies can often occur together in patterns.
Patterns of anomalies that create a recognizable phenotype are known as syndromes. This is often due to a single causative event, such as a chromosome abnormality. When a single major anomaly alters the subsequent development of other structures, this pattern of defects is called a sequence. Anomalies that occur together more frequently than expected by chance alone are called associations.
However, these usually don't have a well-defined, unifying etiology. In many cases, a careful review of the medical and family history and a detailed physical exam can suggest an underlying etiology. If a genetic cause is suspected, cytogenetic, biochemical, and or molecular studies may be warranted. While management is specific to the diagnosis, Always remember to include parental counseling and support.