Fetal Tissue Used to Prevent Blindness in Patients
Stevens-Johnson syndrome (SJS) is a debilitating threat to health that in its most serious form can lead to blindness. It is life-threatening skin condition that is believed to be caused by the development of an immune system disorder. This disease is typically triggered by an over-reaction to a medicine or via an infection such as with the herpes simplex virus, Epstein-Barr virus, mumps, influenza, cat-scratch fever or mycoplasma pneumoniae.
In milder cases of SJS the skin erupts into rashes, but can then progress into blisters that eventually lead to a sloughing off of skin—not unlike that following a serious burn. When more than 30 % of the body surface is affected by blistering it is then referred to as “toxic epidermal necrolysis (TEN), which requires comprehensive medical attention.
With proper treatment, a patient suffering from SJS/TEN can survive; however, between 50-80% of patients become blind due to the skin eruptions developing on the eyes leaving scarring behind.
To help prevent blindness in such patients, medical researchers from the Loyola University Medical Center have turned to analyzing the use of fetal tissues derived from the amniotic sac that protects a fetus while in its mother’s body. The amnion develops from a subset of cells from the earliest stages of fetal development. Its use in medical research is typically obtained from donations by a mother after her baby is born.
In previous studies, amniotic tissue applied directly to the eyes has shown some success toward treating the eyes of patients with late stage SJS/TEN. The amniotic tissue was discovered to help aid healing and decrease inflammation and minimize scarring caused by the disease.
In a more recent study published online in the journal Cornea, researchers wanted to determine whether applying the amniotic sac fetal tissue on the eyes of patients during the early stages of SJDS/TEN would benefit patients even more than when applied during later stages of the disease.
To answer this question, the Loyola researchers dug through the medical records of 128 SJS/TEN patients who had been treated at the Loyola University Medical Center Burn Intensive Care Unit from 1998 to 2010 and made a comparative study between patients who had received amniotic membrane tissue transplants on their eyes and those who did not—but received convention medical treatment for their eyes.
What the researchers found was that of the patients who received convention medical treatment for their eyes without the fetal tissue, approximately 35% of them developed sufficient eye damage to qualify as being legally blind. However, of the patients who did receive the fetal tissue transplant, only slightly over 4% became legally blind.
The researchers reached the conclusion that early application of fetal amniotic membrane to the eyes is beneficial to patients and wrote: "Our results support the use of early amniotic membrane transplantation, within the first three to five days, over the entire ocular surface . . . If the amniotic membrane is placed more than one week after the onset of the disease, the beneficial effects may be reduced."
Future studies are planned toward examining the levels of a range of inflammatory biomolecules in the skin, blood, eye and mouth of patients with SJS/TEN to increase the understanding of the disease and to develop other future treatments and therapies for this debilitating disease.
Reference: “Indications and Outcomes of Amniotic Membrane Transplantation in the Management of Acute Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: A Case-Control Study” Cornea: published online ahead of print April 2012; Hsu, Maylon MD; Jayaram, Anupam MD; Verner, Ruth BS; Lin, Amy MD; and Bouchard, Charles MD.