The following statement describing Isabelle's illness in straightforward terms was provided Dr. Craig Mullen, M.D., Ph.D., Professor of Pediatrics and Chief of Pediatric Hematology/Oncology at the Golisano Children's Hospital in Rochester, New York.

Isabelle suffers from a condition known as Hemophagocytic Lymphohistiocytosis (HLH). It is a rare condition that can have quite a variety of manifestations or symptoms. It is a very serious disease, and in most cases, if left untreated, proves fatal in a few months. In HLH portions of the body’s immune system become activated inappropriately and no longer respond to the normal controls our body places on the immune system. As a consequence of this unchecked activation these cells attack other healthy cells and tissues in the patient’s body. The particular symptoms relate to what tissues are attacked. Various organs in the body can be attacked including the bone marrow, the liver, the brain, the lungs, the intestines, and nearly every other organ. Even though the immune system is highly activated, the body cannot properly fight infections. These infections can also threaten the patient’s life.

No one knows the exact cause of HLH. In some cases it is due to a mutation in genes that are related to the immune system. The patient may inherit the genes from the parents, and consequently other brothers or sisters may develop the same condition. In other cases some infection may trigger uncontrolled activation of the immune system.

Treatment can save the patient’s life. It consists of medicines that help suppress the immune system’s inappropriate activity and medicines that prevent immune cells from proliferating. Medicines used most commonly are dexamethasone, cyclosporine and etoposide (VP-16). The treatment is very intensive and is administered from three to 12 months. In some cases these medicines can cure the disease. In other cases they can only induce a temporary remission. For patients in this latter condition, bone marrow transplant can produce cure. The best donors are a matched brother or sister, but techniques exist for finding a good bone marrow match from an unrelated person. Like the chemotherapy, bone marrow transplant is an intensive and dangerous procedure. However, for some patients it provides the only hope for cure.

I hope this information is helpful to you.