Histiocytosis Syndrome - Abnormal Histiocytes in Abnormal Places

Introduction

Histiocytosis, also known as Langerhans cell histiocytosis, is a group of the syndrome in which the white blood cells or immune cells (macrophages and monocytes) called histiocytes grow to abnormal sizes. It is further classified into different groups, which include:

• C Group - This group is derived from non-Langerhans cells that involve the skin.

• M Group - It includes malignant histiocytosis.

• R Group - It includes Rosai-Dorfman disease.

• H Group - It includes hemophagocytic lymphohistiocytosis.

What Is Histiocytosis Syndrome?

A histiocyte is an immune cell located in many body parts, such as the bone marrow, lungs, liver, skin, and the bloodstream. It is a rare disorder and is said to be caused due to genetic mutations. In histiocytosis syndrome, the histiocytes move around in the body parts where they are not usually present, leading to tissue damage. When it affects one part of the body, it is classified as a single system; when more than one part of the body is affected, it is classified as a multisystem. It primarily affects children, and the skull is affected frequently.

What Causes Histiocytosis Syndrome?

The histiocytosis syndrome is said to be caused by abnormal or immature Langerhans cells. The abnormal number or size of Langerhans cells occurs due to gene mutation. The mutation occurs when a defect in DNA replication leads to abnormal cell growth. As a result, these cells increase in different parts of the body, such as the lungs, skin, and bones.

What Are the Symptoms of Histiocytosis Syndrome?

The symptoms vary depending on the part of the body it has affected. Some of the common symptoms include:

• Nausea and vomiting.

• Poor appetite.

• Ear infection or fluid discharge from the ear.

• A lump or swelling around the bones.

• Jaundice (yellowing of the skin and whites of the eyes).

• Frequent rashes on the scalp.

• Weight loss.

• Frequent urge to urinate.

• Extreme thirst.

• Fever.

• Fatigue.

• Diarrhea.

• Swollen gums and loosening of teeth.

• Easy fracture or broken bone just because of a minor injury.

• Headache.

• Dizziness.

• Cough.

• Difficulty in breathing.

• Bulging eyes.

• Swollen lymph nodes.

• Seizures.

• Anemia.

• Mental deterioration.

• Limping.

• Delayed puberty.

How Is Histiocytosis Syndrome Diagnosed?

Some of the tests that help in the diagnosis of this condition in children and adults include:

• Skin Biopsy - Depending on the area of the skin that has to be tested, a healthcare professional will make a circle or outline it. Then, local anesthesia is given to the patient on the marked site to numb the area. The skin biopsy can be done in two methods. First, shave biopsy, in which a sharp scalpel is used, which cuts the skin tissue and may cause bleeding after collecting the sample. The second is a punch biopsy in which the top layer of fat is cut, and stitches are given to close the wound. Skin biopsies help detect the Langerhans cells in children and adults, any mass or tumor.

• Imaging Test - Different imaging tests are done to get a clearer picture of the tumors or mass caused due to Langerhans cells. CT (computed tomography) scan uses specialized machines and computers to see the images of the body. MRI (magnetic resonance imaging) uses high and powerful magnetic waves to get detailed body images.

• PET Scan - Positron emission tomography scan or PET scan is also an imaging test that helps detect tissues and organs' biochemical or metabolic functions. The machine of PET scan machines are similar to MRI or CT scans. First, the patient is asked to lie down on the platform, which slides into the machine. Next, the machine scans the body from different angles and completes in around half an hour.

• Genetic Testing - A genetic test is done to confirm the diagnosis by examining the DNA and changes in the genes that cause histiocytosis. Depending on the condition, genetic testing can be done by various methods. One of the most common methods includes a blood test. A healthcare professional will take the blood sample from the arm’s vein. A small amount of the blood is drawn out in a vial or a test tube and sent to the laboratory for further testing. If the genetic test result comes out positive, it denotes the presence of the syndrome in the body.

How Is Histiocytosis Syndrome Managed?

In many cases where the symptoms are mild, like skin lesions, there is no need for treatment as it goes away on its own. However, some of the methods through which it can be managed include:

• Chemotherapy - It is a drug-induced treatment that uses powerful chemicals to kill abnormal or fast-growing cells. If the chemotherapy is given intravenously, a healthcare professional will attach a catheter to a large vein (usually in the chest), and the drug is given.

• Radiation Therapy - Also known as radiotherapy, that uses high radiation energy to kill the cancer cells. A high-energy beam is targeted from a machine on the affected part of the body. The radiation damages the cells, which slows down abnormal cell growth.

• Medications - Etoposide, Methotrexate, and Cyclophosphamide are some of the drugs given to treat this condition.

• Additional Treatment - Some additional treatment options, such as physical therapy, special scalp shampoo for rashes, and breathing support therapy, can help improve the conditions.

Conclusion

Histiocytosis can be challenging if it involves bone marrow or other organs. It can lead to long-term side effects, such as hearing loss or neurological disorders. However, if the symptoms are mild and are diagnosed early, they may heal on their own without taking any treatment. Chemotherapy and radiation therapy help in destroying unhealthy cells. In most cases, histiocytosis patients respond well to the treatment and have significantly fewer chances of recurrence. Quitting smoking can help patients whose lungs are affected, and a healthy diet (as advised by the doctor) helps regain the lost weight.