Congenital Anomaly is a physical abnormality present at birth. Congenital anomalies, also called BIRTH DEFECTS, can affect nearly any structure in the body and may be hereditary or random. GENETIC DISORDERS and exposure to teratogens (substances, such as drugs, that alter the development of the embryo or fetus) account for the majority of congenital anomalies. The symptom constellations that characterize CHROMOSOMAL DISORDERS typically contain multiple congenital anomalies.
Some congenital anomalies are almost always treatable, such as atrial septal defect (an abnormal opening in the septum, or wall, between the two atria in the HEART) or CLEFT PALATE/CLEFT PALATE AND LIP (failure of the oral structures to properly close). Other congenital anomalies are life-altering or life-threatening, such as severe forms of SPINA BIFIDA (in which the spine fails to form properly) or transposition of the great arteries (incorrect alignment of the major BLOOD vessels in the heart).
Many congenital anomalies are physically apparent at birth or manifest symptoms that reveal their presence. An infant born with congenital anomalies of the heart, for example, may have a bluish hue to the SKIN (CYANOSIS) that indicates insufficient oxygen to the tissues. The diagnostic path may include imaging procedures such as ULTRASOUND, COMPUTED TOMOGRAPHY (CT) SCAN, and MAGNETIC RESONANCE IMAGING (MRI) that allow the neonatologist to visualize and identify the anomaly. GENETIC TESTING may also be appropriate, depending on the nature of the anomaly. Treatment depends on the type, extensiveness, and complexity of the anomaly. Surgeons often can easily repair isolated anomalies, such as cleft lip or atrial septal defect, with minimal or no residual consequences. Extensive or multisystem anomalies may not be treatable.
See also CONGENITAL HEART DISEASE; HORSESHOE KIDNEY; REPLICATION ERROR.
Resource: Facts On File Encyclopedia Of Health And Medicine
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