What Is Mowat-Wilson Syndrome?

Mowat-Wilson syndrome is a rare congenital abnormality caused by a defective gene. Children born with this syndrome exhibit a mixture of similar symptoms. Many have Hirschsprung disease, an intestinal malady that can cause intestinal blockage, chronic constipation, and bloating, and which can lead to anemia. This is so common that Mowat-Wilson syndrome is sometimes known as Hirschsprung disease — mental retardation syndrome. Some other symptoms are mental retardation, delayed development, heart defects, epileptic seizures, and microcephaly, which is an abnormally small head.

This syndrome affects both genders and has been seen in various ethnic groups. The signs of this genetic anomaly are very apparent in the facial features of some people. In addition to the microcephaly, many are born with pointed chins, oversized eyebrows, wide noses, and microphthalmia, or unusually small eyes. These features commonly become more noticeable as the individual matures, which is why Mowat-Wilson syndrome often isn’t diagnosed until later in life. For example, the small head characteristic of Mowat-Wilson syndrome may not be present at birth and may only show up after several years of delayed development.

The disease is usually diagnosed based on the various symptoms a child displays rather than on genetic testing. Since there is often a delay in the appearance of the obvious facial features characteristic of this syndrome, misdiagnosis is common. The wide variation of symptoms experienced by children with this syndrome also makes early diagnosis problematic.

Problems with the urinary and genital tracts are very common with Mowat-Wilson syndrome. Males often have hypospadias, a condition where the opening to the urethra is located underneath the penis, instead of at the tip. Less common are dental abnormalities and malformation of the hands and feet. Skin color may also be affected.

Children with Mowat-Wilson syndrome often experience delays in learning to sit, stand, speak, and walk. Many have speech impediments, and some never develop the ability to speak. Those who cannot speak can often understand what others say, however, and some develop a unique sign language to communicate their desires.

It is believed that the syndrome is caused by a sudden gene mutation since there is no history of any predisposition in families. There is no cure. The symptoms can be treated, and surgery is sometimes indicated for the heart defects and abnormalities of the urinary and genital tract. In spite of the multitude of health problems that accompany it, people with Mowat-Wilson syndrome generally are happy and friendly.