Hecht-Scott Syndrome - Symptoms and Management

Introduction.

Hecht-Scott syndrome is also known as fibular aplasia, tibial campomelia, and oligo syndactyly syndrome. It is a rare congenital disease that causes limb malformations with an incidence rate of less than 1 in one million. The other names for this syndrome include limb deficiency-heart malformation syndrome, FATCO syndrome, and terminal transverse defects of the limbs associated with congenital heart malformations. This syndrome's outcome can differ for each person depending on how bad the symptoms are and how well they respond to treatment.

What Is Hecht-Scott Syndrome?

Hetch-Scott syndrome is a rare genetic disorder mainly affecting the lower limbs. Hecht-Scott syndrome is characterized by limb malformations, including aplasia or hypoplasia of the fibula, campomelia of the tibia, and oligo syndactyly of the lower limbs. Additionally, affected individuals may have a cleft palate and other abnormalities of the skull, face, and limbs.

What Is the History of Hecht-Scott Syndrome?

Charles.I. Scott jr and Jacqueline.T. Hecht first described Hecht-Scott syndrome in 1981. They described the symptoms in male and female half-siblings. This allowed them to narrow it down to a genetic etiology with an autosomal dominant inheritance pattern.

Later, in 2005, Courtens et al. published findings on FATCO (Fibular Aplasia Tibial Campomelia and Oligosyndactyly) in the American Journal of Medical Genetics. The case identified by Courtens et al. was similar to that described by Hecht and Scott and to five other cases already published in the literature. Then, it was proposed to be called FATCO syndrome, and it was already called Hecht-Scott syndrome, named after those who first described it.

What Is the Cause of Hecht-Scott Syndrome?

• Hecht-Scott syndrome is thought to be caused due to genetic mutations, but the exact genes involved and the cause for gene mutations are unknown.

• This syndrome is believed to be of autosomal dominant inheritance pattern, which means one copy of the mutated gene is enough to cause the disease.

• Genetic mutations can also occur randomly during the development of an embryo, even in families with no prior history of the conditions. In such a case, the individual is said to have a ‘de Novo mutation, which means the mutation occurred spontaneously and was not inherited from either parent.

What Are the Symptoms of Hecht-Scott Syndrome?

Symptoms of Hecht-Scott syndrome start appearing during pregnancy and as a newborn. Symptoms of this syndrome can vary widely in severity and presentation among affected individuals. Some of the most commonly observed symptoms are listed below.

• Abnormality of the Fibula - The fibula is one of the two calf bones of the lower leg. A common feature of the Hecht-Scott syndrome is the absence or underdevelopment of the fibula bone. Deformity of the fibula may result in limb shortening and deformities in the feet and ankle joints.

• Abnormality of the Tibia - Tibia is the shin bone. Abnormal curvature or campomelia of the tibia is a main feature of this syndrome.

• Finger Syndactyly- Decreased fingers and toes with the digits sometimes fused. There is fusion or webbing of fingers on either the soft part or along with the bony portion.

• Short Stature - A decreased body height with a less-than-normal height according to age and gender.

• Premature birth.

• Abnormalities of the cardiovascular system.

• Absent hand with no bony element distal to radius and ulna.

• Respiratory insufficiency.

• Fused ankle bones or tarsal synostosis.

• Cleft palate.

• Abnormalities of the hip, knee, and elbow joints.

How Is Hecht-Scott Syndrome Diagnosed?

• Prenatal screening can help diagnose uterine Hecht-Scott syndrome by observing skeletal abnormalities.

• After the baby is born, a diagnosis can be made through clinical evaluation, imaging studies, and genetic testing.

• Physical examination of the patient reveals characteristic features such as limb shortening, limb deformities, and oligo syndactyly.

• Imaging studies such as X-rays or MRI scans can provide more detailed information about skeletal abnormalities and help guide treatment planning.

• Genetic tests can help confirm the diagnosis by identifying genetic mutations. Genetic tests can also help identify carriers of the mutated gene, which can be important for family planning and genetic counseling.

• Since it is a rare condition, the diagnosis can be challenging, and it may be helpful to consult with a medical geneticist or other specialists with experience in diagnosing and managing rare genetic disorders.

How Is Hecht-Scott Syndrome Managed?

There is no prevention or cure for Hecht-Scott syndrome, as the exact cause of the syndrome is unknown. Treatment involves a multidisciplinary approach to improve mobility and manage complications associated with the syndrome's skeletal abnormalities and other features. Some of the treatment procedures include:

• Orthopedic Interventions - Depending on the severity of the limb deformities, surgical interventions such as limb lengthening or corrective osteotomies can improve mobility and reduce pain. Epiphysiodesis, a pediatric orthopedic surgical procedure that alters or stops normal bone growth, may also be done in some cases.

• Prosthetic Devices - Prosthetic devices such as orthoses or artificial limbs compensate for limb deformities and improve mobility. Orthotics are externally applied devices for foot deformities. Prostheses are used to replace the missing part to restore normal function.

• Early amputations in a nonfunctional leg or more than 50% shorter than normal at birth are carried out. After amputations, the prosthesis is fitted in the early stages.

• Treatment of associated conditions like cleft palate and heart defects is done.

• Physiotherapy is done to improve the function, mobility, and strength of the affected area.

• Genetic counseling can provide information about the inheritance pattern of the syndrome and the risks of passing on the mutated gene to the offspring.

• The management of Hecht-Scott syndrome can be complex and may require ongoing care from a team of specialists, including orthopedic surgeons, geneticists, physiotherapists, and other healthcare professionals.

Conclusion.

The genetic cause of Hecht-Scott syndrome has not been identified yet. Therefore, diagnosis in the prenatal stages remains difficult. Genetic counseling and educating the parents about the condition are very important in managing the syndrome. Though the management of Hecht-Scott syndrome is challenging, early diagnosis and intervention can help improve mobility and quality of life for affected individuals. In the future, more research might help understand the syndrome’s origins and find better treatments. This can give hope for a better future for people with Hecht-Scott syndrome and their families.