Symptoms of this disease
Children with HLH are often very ill, have a high fever that does not respond to antibiotics, large lymph nodes and a low blood cell count. With HLH, the problem usually lies in the (defective) functioning of certain types of immune cells in the blood. Those immune cells cannot fully implement their defense mechanisms. Because the immune system still tries to optimize the defense, there is an uncontrolled division of immune cells which leads to an enormous excretion of inflammatory proteins. Ultimately, this inflammatory reaction leads to the breakdown of blood cells (hemophagocytosis), organ damage and symptoms of high fever, skin rash, enlarged liver and spleen, lymph node enlargement and sometimes also neurological symptoms.
How do we make the diagnosis?
The diagnosis is made by a combination of symptoms in the child, blood tests to determine the blood cell count and inflammatory values and additional research into a hereditary cause of HLH. There are both hereditary (primary) forms of HLH and forms of the disease that occur as a side effect of infection, rheumatological diseases or forms of cancer (secondary HLH). So far, only a small number of genes have been discovered that can directly lead to the hereditary form of HLH on contact with, for example, a virus. More HLH genes will undoubtedly be discovered in the future.
Treatment of HLH
The first step in the treatment of HLH is getting the infection under control. This only works with a combination of drugs that suppress infection (immune suppression) and chemotherapy.
For the hereditary forms of HLH it is then necessary, as soon as the disease is calm, to carry out a stem cell transplantation with donor cells. For the non-hereditary forms of HLH, the disease may remain under control and not return after treatment and the phasing out of medication. If the disease does return, a stem cell transplant will still be carried out.
Children and teenagers with HLH are treated in the Hematology-oncology department.