What Is Fryns Syndrome?

Have you ever been told that you have Fryns Syndrome or that your baby was born with it, and you have no idea what this means and how it could have happened as you are completely healthy? No need to worry as everything has been explained in this article, starting with what Fryns Syndrome is, its signs and symptoms, and diagnosis, all the way to treatment options and frequently asked questions.

Fryns Syndrome is a rare inherited disorder that is mainly classified as anatomic abnormalities at birth, such as defects in the diaphragm, specific facial features, and incomplete development of certain organs and parts of the body.

This genetic disease is linked to high mortality due to the anatomical anomalies present. There is no cure. However, treatment related to symptom management is available. 

Overview

Fryns Syndrome is an extremely rare genetic condition that is most closely associated with congenital diaphragmatic hernia (CDH), as it has been estimated that more than 90% of patients diagnosed with Fryns Syndrome are also suffering from Congenital Diaphragmatic Hernia.¹ CDH is described as a whole located at your diaphragm, which is a sheet-like-looking muscle that separates the abdomen from the chest cavity.² This could be life-threatening as organs found in the abdominal cavity, such as the liver, intestines, and stomach, can move into your chest cavity, where your heart and lungs are located. However, it is important to note that not everyone with CDH is actually suffering from Fryns disease. This genetic disorder is inherited in an autosomal recessive fashion, and therefore, two copies of the faulty gene have to be passed down, one from each parent. This would mean that both parents have to be carriers in order for some of their offspring to develop Fryns Syndrome.

What is fryns syndrome?

Fryns Syndrome is an extremely rare autosomal recessive genetic condition that is characterized by abnormal anatomical development of the patient. It is present at birth and has a very high mortality rate as most patients do not survive past the neonatal stage ( first 4 weeks after birth). Carriers of Fryns Syndrome are asymptomatic, and therefore, if not tested, they would not know they are carrying a faulty copy of one or more disease-related genes. Both parents need to be carriers, also called heterozygous carriers, for a chance of 25% or 1 in 4 chance that one of their babies would be born with Fryns Syndrome. If both parents are carriers, there is also a 50% chance that their offspring will be asymptomatic carriers, and 25% of their children will be completely healthy.

Diagnosis 

Family history would be a very good indicator of fryns syndrome. Other methods include criteria fulfilment upon clinical examination and genetic testing for one of the faulty related genes.³

• Clinical diagnosis- Clinical diagnosis is made through observation of any related signs and symptoms upon clinical examination by a professional. 
• Molecular Diagnosis- testing for disease-related genes. A faulty PIGN gene has been associated with Fryns Syndrome. Other genes are also thought to be related to Fryns Syndrome.

Diagnosis can be made with the help of different imaging methods, such as:

• Magnetic Resonance Imaging scan (MRI)
• Computerized Tomography scan (CT)
• Ultrasound- Sometimes anatomical malformation can be seen in the fetus while still in the womb

Both MRI and CT scans can help provide an internal image of the human body, giving information if there is anything abnormal.

Signs and symptoms

The degree of severity of signs and symptoms greatly varies between individuals. There are suggested diagnostic criteria that would result in Fryns Syndrome diagnosis upon clinical exam:

• Diaphragmatic defect- e.g. Congenital Diaphragmatic Hernia
• Specific facial appearance- e.g. coarse face, eyes wider apart, a wide and depressed nasal bridge.
• Abnormal/ underdeveloped phalanges/bones of the fingers and toes/ (distal digital hypoplasia)- underdevelopment of the fingers and toes. Found in around 60% of patients.
• Lung underdevelopment (pulmonary hypoplasia)
• Characteristic anomalies- e.g. Gastrointestinal tract and Genitourinary tract anomaly (~10%), Cardiovascular anomaly, cloudy appearance of the corneas (clear, outer area of the eyes), Brain anomaly (e,g, seizures).

Consanguineous families (closely related parents- e.g. first cousins) are more likely to have offspring that will develop Fryns Syndrome as they share similar genetic information.

Treatment

There is no cure for Fryns Syndrome as of present. However, clinical trials are ongoing, looking at different ways to treat a congenital diaphragmatic hernia. In the meantime, management of symptoms is the best treatment for Fryns Syndrome. For patients with CDH, surgery could be performed. Children with CDH would most likely be intubated to prevent any further complications. Frequent consultations and visits with different health professionals, such as a nephrologist, a cardiologist, a gastroenterologist, etc., are strongly advised.

Disorders with similar symptoms

Sometimes, symptoms can overlap in different diseases, making it more difficult to provide an accurate diagnosis. Some of the health conditions have symptoms similar to Fryns Syndrome.¹

• Pallister- Killian Syndrome- an inherited disorder associated with unique facial appearance, intellectual disability, and seizures. Babies may also have diaphragmatic hernia.
• Cornelia de Lange Syndrome (CdLS)- genetic disease. Symptoms include- delayed growth, malformations of the upper limb (hands and arms), distinctive facial appearance, and ranging degrees of intellectual disability.
• Donnai- Barrow Syndrome-genetic disorder. Symptoms- CDH, intellectual disability, unique facial features, hearing loss.
• Matthew- Wood Syndrome- autosomal recessive disorder. Symptoms- CDH, lung underdevelopment, eye problems.

Summary

Fryns Syndrome is considered an autosomal recessive disorder that has a high mortality chance due to the serious symptoms associated with it. The most common symptom is CDH, which could result in the movement of organs located in the abdominal cavity, such as the liver, inside the thoracic cavity where the heart and lungs are located. Other signs of Fryns Syndrome include wide-set apart eyes, GI and GUI tract anomalies, cardiovascular anomalies, underdevelopment of the fingers and toes, etc. Most babies do not survive past neonatal age ( the first 4 weeks) due to the seriousness of the symptoms. There is no cure. However, management of symptoms is applied as a treatment plan. Diagnosis is made mainly upon clinical examination, looking for specific criteria accounting for Fryns Syndrome, as well as using different imaging techniques to look for internal anomalies. Genetic tests and family history should also be considered when setting a diagnosis.

FAQs

What is fryns syndrome?

Fryns Syndrome is an autosomal recessive inherited disorder that is passed down from both parents who are asymptomatic carriers and may not know they have a faulty gene for the disease. Fryns Syndrome is associated with multiple internal anatomical malformations such as brain, cardiovascular, gastrointestinal, and genitourinary tract anomalies.

What causes fryns syndrome?

A set specific cause has not been determined, but Fryns Syndrome is thought to be most likely caused by a genetic mutation. One of the genes thought to be associated with Fryns Syndrome is the PIGN gene.

What are the most common signs and symptoms of fryns syndrome?

Congenital Diaphragmatic Hernia (CDH), wide-apart set eyes, underdeveloped fingers and toes, malformations in the brain, cardiovascular system, GI- and GUI-tract.

Is there a cure for fryns syndrome?

There is no cure for Fryns Syndrome. However, there are treatment options, target management of signs and symptoms, and preventing further complications.

How is fryns syndrome diagnosed?

Fryns Syndrome is usually diagnosed via clinical examination by a professional, genetic testing, imaging methods such as ultrasounds, MRI- and CT-scans, and family history.