Heart and Blood Conditions

Langerhans Cell Histiocytosis

What is Langerhans cell histiocytosis?

In Langerhans cell histiocytosis (pronounced his-tio-cy-TO-sis), certain white blood cells, called Langerhans cells, grow out of control.

In a healthy person, these cells help defend against infection. But in histiocytosis, the cells multiply so quickly that they build up and can damage the body instead of protect it.

This disease is not cancer, but it has the similar characteristic of rapid cell growth. Except for their rapid growth, the cells are normal. Doctors who treat cancer and blood diseases also treat histiocytosis.

Some people with the disease have excess cells and damage in only 1 site or organ in their bodies. Others have excess cells in many places throughout their bodies.

The bones are the most common sites of damage — mainly the bones in the skull, but also in other places, such as the spine, arms and legs. This disease can affect many body systems.

About 80% to 90% of children recover from this disease with treatment. Sometimes it goes away slowly on its own. It can be serious, even fatal in severe cases. It can also come back later in life.

Langerhans cell histiocytosis has had other names, and there are subtypes of the disease. So you may hear or see one of these names:

  • Diffuse reticuloendotheliosis
  • Eosinophilic granuloma
  • Hand-Schüller-Christian disease
  • Hashimoto-Pritzker syndrome
  • Histiocytosis X
  • Langerhans cell granulomatosis
  • Letterer-Siwe disease
  • Non-lipid reticuloendotheliosis
  • Type II histiocytosis

Langerhans Cell Histiocytosis in Children

A person of any age can get histiocytosis, but it is more common in children. About three-quarters of people with the disease get it before age 10. It is most common in children 1 to 3 years old.

Doctors do not know what causes this disease, but they are actively researching the causes and treatments. The disease may develop because of a problem in the person’s immune system. It is not inherited and not passed from person to person.

Langerhans Cell Histiocytosis at Seattle Children’s

This is a rare disease, and not many doctors have experience treating it. Our doctors at Seattle Children’s do. They have worked with many children with histiocytosis and can offer the latest treatments for your child.

Pediatric cancer doctors (oncologists) coordinate the care for histiocytosis because it is so specialized and may vary greatly from patient to patient. Your child’s team will carefully check your child’s health to understand exactly how they are affected and then tailor treatment to their needs.

Nurse practitioners, surgeons and other specialists may take part in your child’s care based on how your child is affected. Seattle Children’s has experts from many areas of healthcare, so we can take care of all aspects of your child’s health.

The type of surgeon your child needs depends on where your child has the disease. For example, an orthopedic surgeon treats disease in the bone. Neurosurgeons or ear, nose and throat doctors (otorhinolaryngologists) most often treat disease in the skull.

If the disease affects your child’s growth, hearing, movement, speech or other functions, we will involve the Seattle Children’s experts who focus on these needs.

Read more about cancer programs and services at Seattle Children’s.