Welcome to the Rare Classroom, a new series from Patient Worthy. Rare Classroom is designed for the curious reader who wants to get informed on some of the rarest, most mysterious diseases and conditions. There are thousands of rare diseases out there, but only a very small number of them have viable treatments and regularly make the news. This series is an opportunity to learn the basics about some of the diseases that almost no one hears much about or that we otherwise haven’t been able to report on very often.

Eyes front and ears open. Class is now in session.

The disease that we will be learning about today is:

VACTERL Association

Also known as VATER association or VACTERL syndrome.

What is VACTERL Association?

• VACTERL association is a group of birth defects known to occur together
• This pattern is considered an association instead of a syndrome because there is no known cause to explain why the recognized features occur together
• Most cases are unique; some are lethal
• VACTERL association specifically refers to recognized abnormalities impacting structures that are developed from the embryonic mesoderm.
  • The mesoderm is the middle layer of the three germ layers that appear during gastrulation, a process that takes place during the early embryonic development of most forms of animal life.
• Prevalence of the association is estimated to range from 1 in 10,000 to 1 in 40,000 births
• VACTERL association was first described in 1972 by David Smith and Linda Quan, an emergency room physician.

How Do You Get it?

• The cause of VACTERL association is unknown
  • A specific abnormality affecting the chromosomes or genes hasn’t been linked to the association
• Risk factors include diabetes in the mother
• VACTERL association is sometimes associated with the trisomy 18, a genetic disorder characterized by the presence of the third full or partial copy of chromosome 18
• The association is most likely the result of a number of converging factors
• Other conditions linked to VACTERL association include Goldenhar syndrome and Klippel-Feil syndrome
• The illness may occur sporadically, but instances of occurrence in families have been recorded, suggesting an inherited genetic factor is involved.

What Are The Symptoms?

• VACTERL association impacts a number of body structures
  • V= Vertebral anomalies
  • A= Anorectal anomalies
  • C= Cardiovascular anomalies
  • T= Tracheoesophageal fistula
  • E= Esophageal atresia
  • R= Renal/radial anomalies
  • L= Limb defects
• Spinal
  • Abnormalities consist of partially formed bones or underdeveloped vertebrae. These rarely cause problems at first, but patients are at a high risk of scoliosis later on.
• Anal
  • Imperforate anus or anal atresia takes place in around 55 percent of cases.
• Cardiac
  • Congenital heart disease affects 75 percent of patients. This can encompass a number of heart defects.
• Tracheal and Esophageal
  • Problems affecting the trachea and esophagus impact around 70 percent of cases.
• Renal
  • Kidney defects impact around half of VACTERL association patients. In some cases, the kidneys are not fully formed.
• Limbs
  • Limb problems appear in 70 percent of cases. Examples include forearm defects, extra digits, and thumb hypoplasia.
• Other signs and symptoms noted in VACTERL association include ambiguous genitalia, intestinal abnormalities, respiratory abnormalities, defects of the abdominal wall, and diaphragmatic hernia.

How Is It Treated?

• For urgent problems such as imperforate anus, surgery is often performed as soon as possible.
• There is universal standard treatment approach for VACTERL association since each case is unique. Instead, the treatment plan is based on addressing the signs and symptoms that are present.
• Due to the wide range of symptoms, a team of specialists is often required for effective treatment.
• Outcomes vary widely in VACTERL Association. Some patients are born with severe complications that are ultimately fatal. Others will continue to affected by their malformation throughout their lives. However, with optimal surgical outcomes, prognosis can be favorable.

Where Can I Learn More???

• Check out our cornerstone on this disease here.
• Learn more about this condition from the National Organization for Rare Disorders.