Histiocytosis
Diagnosis

Your child's doctor may order one or more of the following tests to aid in the diagnosis of histiocytosis.

• Bone X-ray — A diagnostic test that uses invisible electromagnetic energy beams to produce images of internal tissues, bones and organs onto film.



• Skeletal Survey X-ray — X-rays of the entire skeleton to determine the degree of bone involvement.



• Complete Blood Count (CBC) — A CBC is a blood-screening test used to diagnose and manage numerous diseases. It can reflect problems with fluid volume, such as loss of blood. It can show abnormalities in the production, life span, and destruction of blood cells, which is an indication of an infection and problems with clotting.



• Biopsy — A biopsy of skin performed to check for the presence of Langerhan's cells.



• Bone Marrow Aspiration — Bone marrow obtained to check for the presence of Langerhan's cells. In bone marrow aspiration, cells are removed from the bone marrow, a spongy network of tissues inside the bones, to check for evidence of histiocytosis. Depending upon the diagnosis, this procedure may be done periodically throughout your child's treatment.



• Bone Marrow Biopsy — Immediately after a bone marrow aspiration, your child also may undergo a bone marrow biopsy to remove a small core of bone marrow. This procedure is necessary to confirm the presence of histiocytosis because the liquid part of bone marrow may not contain enough cells.

A bone marrow aspiration and biopsy usually takes 15 to 20 minutes to complete. Understandably, bone marrow aspirations may be frightening to you and your child. A local anesthetic is injected deep under the skin to numb the puncture site and takes effect quickly, helping to control the pain. Whenever possible, we give you the choice of having the procedure performed under general anesthesia.

A bone marrow biopsy is usually performed at the same site as the aspirate. Although the biopsy needle may look frightening, only a very small sample of the spongy bone marrow is removed, using a procedure similar to bone marrow aspiration. The difference is that a side-to-side motion of the needle is used to take out a small sample of the spongy bone marrow, which is the most painful part of the procedure.

Reviewed by health care specialists at UCSF Benioff Children's Hospital.