WHAT IS A GOOD APPROACH TO THINKING ABOUT A CHILD WITH MULTIPLE DYSMORPHISMS?

A dysmorphism is difference in a body structure. If the dysmorphia is truly the only abnormality that you see in the child, further evaluation is often unnecessary. Isolated dysmorphisms are typically caused by malformation (abnormal tissue development), deformation (distortion caused by a mechanic force), disruption (destruction of a normal forming structure), or dysplasia (anomaly of growth and differentiation). A patient with multiple dysmorphisms, however, typically requires further workup to arrive at the cause, which could be chromosomal, genetic, or environmental such as in utero exposure to teratogen or infection. 1 Making the diagnosis relies on recognizing the pattern of dysmorphisms. The 4 major patterns to consider are the following 2: Association: Physical features that often occur together more often than would be seen by chance alone, but no single etiology is yet known to explain the pattern. Vertebral anomalies, anal atresia, cardiac defects, trachea esophageal fistula, renal anomalies, and limb anomalies (VACTERL) are examples of associations with no unifying etiology. Sequence: A group of defects that stem from a sequential set of events that began with one malformation. An example is Potter sequence with renal agenesis resulting in no fetal urine production, which leads to severe oligohydramnios with the consequences of lung hypoplasia and intrauterine constraint that cause limb deformities and compressed facial features. Syndrome: A cluster of anomalies that occur in a consistent pattern that has a unifying cause, known or unknown. Developmental field defect: A group of malformations caused by harm to a particular region of the embryo. An example is hemifacial microsomia, unilateral facial hypoplasia, and ear anomalies that come from anomalous development of the first and second brachial arch structures.