What Is Jeune Syndrome?

Jeune Syndrome also called Asphyxiating thoracic dystrophy, is caused by a genetic mutation in children before birth. It is a very rare recessive disorder affecting one in 100,000 children. Few classic symptoms are associated with a bone malformation in newborns. Children with this syndrome show classic skeletal deformation, such as small and bell-shaped rib cages, kidney abnormalities, and bone abnormalities related to the legs. When the fetus is in the embryonic developmental stage, the mutation in the genes is the primary cause of the disorder.

The syndrome is also known as thoracic-pelvic-phalangeal dystrophy, asphyxiating thoracic chondrodystrophy, infantile thoracic dystrophy, and Jeune thoracic dystrophy. Moreover, there are non-skeletal congenital involvements associated with the syndrome, such as cleft lip and anomalies related to the eyes, intestines, genitalia, liver, heart, and pancreas. The small thoracic skeleton can result in respiratory distress and recurrent infections related to the respiratory tract.

What Are the Etiological Factors Behind Jeune Syndrome?

The only cause behind this disorder is a genetic mutation in the infant in the prenatal phase. DNA (deoxyribo nucleic acid) is found at the center of any cell, and genes are a part of it. Each gene has a specific function and importance in the body. For instance, some have the function of instructing proteins to regulate cells, tissues, and organs; some control the on and off switch, and others are involved in creating RNA (ribonucleic acid) to aid in chemical reactions in the body.

The cells have microscopic and elongated protrusions called cilia at the surface, creating proteins at the surface. This structure plays an essential role in chemical signal regulation, one of which is called the sonic hedgehog pathway. These pathways have a major role in the proliferation and differentiation of cells that are involved in the development of cartilage and bones in the body.

When the mutation or abnormalities of the genes and proteins involved in intraflagellar transport (transportation of materials from and to the cilia) are impaired, it, in turn, affects the structure and function of cilia. The abnormalities found in cilia disrupt the sonic hedgehog pathways and that in the same manner, affect the bone structures and other organ development. It is an autosomal recessive pattern, which means both parents carry the same abnormal genes, and the affected infant either carry them with symptoms or just acts as a carrier.

What Are the Signs and Symptoms of Jeune Syndrome?

The Jeune syndrome carries a myriad of skeletal and other structural abnormalities, such as:

• Thoracic Dystrophy: It is a structural bone abnormality of the chest or rib cage.

• Short Height: The skeletal abnormality affects the overall structure of the person as well.

• Blue Colored Skin: Due to low oxygen levels, the skin appears blue.

• Short Arms, Legs, Fingers, and Toes.

• Low Appetite: Children with this syndrome face issues related to eating food due to abnormality of the bone structure.

• Night Sweat: Due to abnormal respiration, the blood flow is also compromised, causing a sudden wave of heat and night sweats.

• Toe Syndactyly: It is also known as the webbing of the toes, where two or more fingers and toes are fused.

• Hypoplasia of Lungs: It is an abnormal and insufficient development of the lungs.

• Brachydactyly: When the bone structure of the fingers and toes is out of proportion, it is called brachydactyly.

• Cone-shaped Epiphysis: When the terminal end of the bone is abnormally structured in a cone shape.

• Micromelia: It is a skeletal defect where proximal and distal bones are abnormally short.

• Nephropathy: Deterioration of the functions of both or one kidney.

• Renal Insufficiency: When the functions of the kidneys are compromised due to poor blood flow, urine output is also affected.

• Skeletal Dysplasia: The term is used for structural abnormality of the bones and the cartilage.

How to Diagnose Jeune Syndrome?

The diagnostic measures used for this syndrome are:

• Case History: It is the first step of the diagnosis. A detailed case history can reveal if the newborn is suffering from genetic disorders or if there are other factors to be considered. Also, if the child is facing any other complications related to the syndrome, this line of diagnosis can help to provide treatment.

• Genetic Testing: If the doctor looks for confirmed etiology and the syndrome, this can be very beneficial.

• X-Rays: It shows any deformities related to bones along with other complications.

• Oxygen and Carbon Dioxide Levels in the Blood: Usually, if the child is born with an abnormally small thoracic skeleton, the chances of affected blood flow and oxygen level are possible.

• Urine Test: If the syndrome has affected the kidneys, this test can reveal the severity and its effects.

• Ultrasound: This test reveals the affected organ and the potential damage this syndrome has caused.

How to Treat Jeune Syndrome?

The treatment plan for this disorder completely relies on the severity and involvement of the syndrome. The bone structures are an essential part of the body because as much as it protects the delicate organs, any deformities can be the reason for fatal health conditions.

Due to the involvement of thoracic bone structure, the child might need to be on breathing support, such as intubation, which can create air pathways for breathing. Respiratory distress is often seen in children who face difficulties in eating food. In such cases, a feeding tube is required for a child to gain proper nutrition.

For children with severe thoracic deformities, doctors usually recommend vertical expandable prosthetic titanium rib surgery (VEPTR). In this surgery, the titanium rods are surgically inserted into ribs in order to create space for the lungs to expand and fully function.

Lastly, the children should go for follow-up visits regularly every two to three weeks after the surgery and as per the doctor’s recommendation.

Conclusion:

Since the syndrome is completely caused by a genetic mutation, it is very important for parents to give detailed information about their genetics if they are aware of it. If not, at least they should take their child for regular doctor's visits as the skeletal deformities can be life-threatening for them. Sometimes the child may require long-term hospital care due to multi-organ involvement. Over there, if required, doctors may suggest the surgical procedure too.