Syndrome amniotic bands (Streeter dysplasia)

Streeter dysplasia is a term used to describe a complex disorder characterized by constrictor rings, and frequently acrosindactilie extremity amputation in newborns.Amniotic band syndrome is similar to that has been recognized since 300 AD Hippocrates suggested that amniotic membranes ruptured external presiunele lead to the formation of skin strips or amputations of limbs.
Streeter dysplasia term was adopted in 1930 when George Streeter suspected a defect in the placenta as a matrix of plausible theories. At that time his theory was accepted because of associated anomalies that occur away from the constriction bands. In 1960 Patterson used histology to show how constriction bands are similar to skin folds caused. A ipotetizat that same lack of development in the mesoderm is transforming a band meet increased skin fold abnormally. His theory was rejected by another researcher who examined the placenta and many sick children. He reintroduced the idea of ​​Hippocrates. He proposed that maternal trauma leads to rupture of amniotic membranes which then turns into strips. These bands and amputeaza strangle.
Constriction amniotic bands extremities can lead to constriction band around the fingers, arms and legs, swollen extremities, lymphedema congenital distal constriction and amputation of fingers, arms and legs, congenital amputation. There is a close relationship between amniotic band syndrome and crooked leg. 30% of these abnormalities are associated with the syndrome, and 20% are bilateral. Other abnormalities observed in patients are crooked hands, cleft lip, palate, and hemangioma.
Amniotic band syndrome is often difficult to diagnose before birth because the bands are small and hard to see the ultrasound. Often bands are detected indirectly due to constriction and edema caused. The diagnosis is often wrong, so if there is suspicion of syndrome serial echography is performed to detect the severity. 3D ultrasound and MRI can be used for a more detailed and precise diagnosis of the bands and the severity of the fetus.
The treatment is performed after delivery and when the plastic and reconstructive surgery is indicated for deformities results. Plastic surgery ranges from simple to complex depending on the extension deformation. Physical and occupational therapy are indicated in the long run. In rare cases, if diagnosed in utero, fetal surgery may be considered to save a member who is in danger of amputation. This operation was performed successfully in only 22 weeks of gestation.
The prognosis depends on the location and severity of constriction bands. Each case is different and multiple bands can be wrapped around the fetus. Bands that wrap fingers cause sindactilie or amputations. In other cases bands can wrap around limbs causing limitation of movement with crooked legs. In more severe cases can cause blood loss and amputation intake. Amniotic bands may be attached to the face and neck causing deformities such as cleft lip or palate. If bands are wrapped around the head or umbilical cord can be life threatening for the fetus.Amnhiotice band syndrome is considered an accidental event and not genetic or hereditary seems, so its appearance in another task is invalid. The cause is unknown amniosului break.
CausesTwo main diseases are treated according to the etiology of amniotic band syndrome.Streeter proposed the existence of an event that occurs during blastogenezei leading to a defect in placental intrinsic matrix. It allows soft tissue to crustifice. Healing scabs external constrictor rings and defects lead to the development side.African Ainhum is a syndrome in which progressive circumferential ulcers leading to amputation fingers. It is an inherited disease that supports the existence of an intrinsic developmental defect as the cause of finger amputation. Streeter defended this theory for more than 35 years, so many doctors describe as a disease Streeter dysplasia.
PathophysiologyEmbryo development is in two cavities: amnios and chorionic. As development takes place in space extracelomic obliterans amnion pressed it. phenomenon occurs at 12 weeks gestation. Incomplete obliteration of space left extracelomic amiosul fragile and subject to spontaneous and traumatic fractures. After rupture occurs oligohydramnios by extravasation of fluid. Chorion is permeable until developing fetus has little space to move. This contributes to disease severity of deformities observed in amniotic bands.
Reduce space allows bands to catch floating amnios easy parts of the body.Circumferential bands early in pregnancy can cause miscarriage. If the constriction occurs after development is almost complete, only cracks, acrosindactilia and intrauterine amputation in the extremities are seen as typical manifestations. If you are swallowed amniotic bands while partial placenta is attached and facial cleft palate appear bizarre.
Signs and symptomsChildren born with amniotic band syndrome are usually at or within a few weeks premature. in most cases are uncomplicated tasks. Although the condition is variable as the variable clinical presentation element occurs in the extremities and include amputation followed by constriction and then acrosindactilia band. Other related items include encephalocele, cleft lip or palate, renal anomalies, heart defects, hemihipertrofia, bulging of the anterolateral tibia, tibial and the gap length pseudoartroza legs.
The distal extremities are involved most often, especially long central hand fingers.Tomorrow is affected in 90% of cases. In rare cases the thumb or little affected because of their short length. The same rule is observed and the legs, which constrict most commonly affects halucele. Affects only light pressure bands indentations at the base of phalanges, distal to the metacarpophalangeal joints. Progressive constriction is the result of maceration indentations and healing by scar formation. If the band is severe compression, and lymphatic vascular compromise can occur and your child has swollen fingers or limbs at birth requiring immediate release angorjate.
Most often the finger is amputated in utero. Acrosindactilia appears after digital separation is complete, but fingers are twisted by the band and eventually merge.Fingers are pushed above peripheral and residual sinus tracts are present in the remaining ring space.
Amniotic band syndrome extremities deformation is divided into four types:Type I involves a single-constriction-Type II contains a constriction accompanied by fusion of distal bony parts, with or without lymphedema-Type III involves the building accompanied by merging parts of soft tissue-Type IV demonstrates intrauterine amputation.
Crooked foot is seen in 25% of cases. It is a mixture of paralytic and idiopathic deformities. 50% of cases are found close to a band around the fibula nerve that causes muscle imbalance and crooked leg. The other 50% of cases are not visible bands on foot. Deformation is considered to arise from lack of space by oligohidraminos. Crooked foot is typically rigid. Clinically significant leg length discrepancy may also be present and patients require sequential monitoring, even after correction and leg bands. Other items include rare craniofacial anomalies occurring in 5% of the syndrome, and bulging pseudoartroza anterolateral tibia.Evolution Streeter dysplasia:Depending on the severity of the defect may be minimal constriction band in a single existence. If there are more lanes can lead to lymphatic obstruction with edema and vascular compromise requiring immediate release. Pressure can cause abnormalities distal bands of constriction as hemihipertrofia, bulging anterolateral, pseudoartroza, discrepannta length between States and teratology flat foot. These conditions can lead to limited function and difficulty ambulatie.
Constriction bands crossing the head and face can lead to facial clefts. If the cleft extends into the skull resulting encephalocele. Bands crossing the body affect the chest: toracoschizis or extratoracic heart, abdomen, gastroschisis.