Contents
Definition
Loeys-Dietz syndrome is a rare, hereditary (autosomal dominant) disease that can cause aneurysms, most often in the main artery. The disease was described in 2005 (reference: Loeys BL, 2005). Later, several forms/subgroups of the disease were detected. Along with vascular form of Ehlers-Danlos syndrome (which also attacks blood vessels) and hereditary thoracic aortic aneurysm (HTAD) the disease is included among the hereditary "Marfan's-like" the diseases. The disease is often investigated by specialists in physical medicine and/or clinical genetics. In Loeys-Dietz syndrome, the connective tissue is incorrectly composed for genetic reasons and not weakened due to rheumatic inflammation. The disease is therefore not one autoimmune" connective tissue disease. Many have had family members who died suddenly at a young age. Correct follow-up and, if necessary, surgery can prevent serious complications and early death.
Occurrence
Loeys-Dietz syndrome is defined as a rare disease, but good data describing the occurrence in more detail is not available. Among subgroups of the disease, Type 1 and Type 2 are most common (please see below)
Disease Cause
Mutations in various genes cause the disease and its subgroups: Type 1 (GFBR1), type 2 (TGFBR2), type 3 (SMAD3), type 4 (TGFB2,) and type 5 (TGFB3). Nevertheless, the disease is most often detected among people without a family history.
Symptoms and investigations
Medical history may include growth disturbances observed already in infancy. These first include a premature closure/fusion of the skull bones and the development of a face shape with a relatively large distance between the eyes.
Clinical examination can also show uvula bifida (cleft in uvula) which is seen in the pharynx and cleft palate. In the back, distortion is seen in the form of scoliosis or kyphosis. The chest can also be affected. Some have a "Marfan's-like /Marfanoid habitus” with long arms, legs, fingers and toes in relation to the body. Most serious is the development of aneurysms i main artery (aorta) and other large arteries or aortic dissection (damage to the blood vessel wall). These rarely cause symptoms before complications arise. The occurrence and severity of aneurysms (with rupture and risk of bleeding) varies from person to person, but can occur already in childhood (Hyung-Tae S, 2015).
Blood tests. Normal inflammation tests such as lowering reaction (SR) and CRP are expected (except in the case of aneurysmal bleeding). Also normal other disease markers. Genetic tests: see genetickportalen.no.
Imaging: MR examination of blood vessels (MR angiography) shows the most important pulses from and including the head, neck, chest, abdominal area and pelvis. A CT examination also provides a good overview, but the examination entails the use of X-rays, which is unfavorable, particularly in the case of repeated examinations in children and young people. Ultrasound Doppler / echocardiography can be used to measure the diameter of the main artery at the heart and the aortic arch.
Diagnosis
Loeys-Dietz syndrome is detected on the basis of suspicion based on symptoms, cases in the immediate family, growth disorders and detection of aneurysms at a young age. Genetic tests are also crucial (genetickportalen.no).
Similar conditions, differential diagnoses
Differential diagnoses are other "Marfan-like" diseases such as Marfan Syndrome, Ehlers-Danlos syndrome and other forms of hereditary connective tissue diseases (HTAD) which can also cause swelling in the main artery (aortic dilatation, most often in the chest area, near the heart).
Treatment
No curative treatment is available. If expansion of the arteries (aneurysms) is detected and increases in size, surgery to prevent the artery from rupturing (aortaruptur) become necessary. Vascular surgeons / thoracic surgeons have guidelines for when operations should be done. Blood pressure measurements are important to detect any high blood pressure that can increase the risk of aortic aneurysms.
In general, regular physical activity is recommended, while intensive, hard physical exercise increases the pressure on the blood vessels and should be avoided.
Cortisone and other immunosuppressive treatment have no place in the treatment of hereditary connective tissue diseases, unlike autoimmune connective tissue disease
Follow-up
Regular control of the blood vessels with imaging (see above) is important. If the pulse vein expands, measurements are made at least every six months, otherwise annually for a longer period in accordance with current guidelines (reference: MacCarric G, 2014 (Dagose and Management).
Literature
- MacCarric G, 2014 (Dagose and Management)
- Yarate YA, 2015 (Aortadilatasjon, extension of the main pulmonary artery) among children and adolescents
- Competence Center: Sunnås Hospital
- Loeys BL, 2005 (original description of the syndrome)
