Waardenburg syndrome Health Article

Definition

Waardenburg syndrome (WS) encompasses several different hereditary disorders, the main features of which variably include abnormal pigmentation, hearing loss, and a subtle difference in facial features. Certain other physical anomalies occur less frequently in WS.

Description

In 1951, Dr. Petrus Waardenburg reported a syndrome of dystopia canthorum, heterochromia of the irides, and hearing loss. Dystopia canthorum (also called telecanthus) describes a subtle but unusual facial feature in which the inner corners of the eyes (canthi) are spaced farther apart than normal, yet the eyes (pupils) themselves are normally spaced. The result is that the eyes appear to be widely spaced, even though they are not. Heterochromia means different-colored, and irides is the plural form of iris—the colored portion of the eye. Thus, someone with heterochromia of the irides has differentcolored eyes, often one brown and one blue. Another feature not originally noted by Dr. Waardenburg, but now considered a major sign of WS is a white forelock (white patch of hair extending back from the front of the scalp). In fact, disturbances in pigmentation (coloring) of various parts of the body are consistent features of WS. Uncommon but serious physical anomalies associated with WS include Hirschprung disease (intestinal malformation), spina bifida, cleft lip/palate, and musculoskeletal abnormalities of the arms.

Five types of WS have been defined based on clinical symptoms or genetic linkage. As of 2000, six different genes were associated with WS. Most families show autosomal dominant inheritance, but autosomal recessive inheritance and sporadic (single) cases are also seen. People with WS are not at increased risk for mental retardation, and vision loss is not more common. For the majority of those with WS, hearing loss is the only major medical problem they will have.

WS1 is the "classic" form of WS, and if someone uses just the name Waardenburg syndrome (with no modifying number), they are most likely referring to the group of disorders as a whole or just WS1. WS2 may occasionally be referred to as WS without dystopia canthorum. WS3 is also known as Klein-Waardenburg syndrome, as well as WS with upper limb anomalies. Alternate names for WS4 include Waardenburg-Hirschprung disease, Waardenburg-Shah syndrome, Shah-Waardenburg syndrome, and Hirschprung disease with pigmentary anomaly.