Fanconi anemia

Overview

Fanconi anemia is a rare genetic disorder of the bone marrow. Bone marrow makes red blood cells (which carry oxygen), white blood cells (which fight infection) and platelets (which allow the blood to clot). All three are key to good health. Children with Fanconi anemia often have abnormally low numbers of white blood cells, red blood cells and platelets. Too few white blood cells can open the door for infections. Too few red blood cells can cause fatigue. And a reduced number of platelets means the blood won't clot as it should and excessive bleeding and bruising may ensue. Eventually, Fanconi anemia leads to bone marrow failure. There is an increased risk of developing leukemia in patients with Fanconi anemia which increases with age.

Signs & symptoms

Many children with Fanconi anemia are born with birth defects, especially to the hands and arms. But up to 40 percent have no obvious clues. For those children, the first sign is often fatigue. Because red blood cells deliver oxygen to every part of the body, when there aren't enough red blood cells to go around, tiredness sets in. Other signs of too few red blood cells can include shortness of breath, dizziness and headaches.

Likewise, too few white blood cells are also a health concern. Without enough infection fighters on board, the body can't fend off illness as easily. Infections may linger and be more serious in those with Fanconi anemia.

A child with Fanconi anemia may also have abnormalities of the heart, lungs, kidneys and gastrointestinal tract. Bone problems are also common, such as curvature of the spine (scoliosis). Other signs associated with this condition include:

• Cafe au lait spots (light-brown birth marks)
• Short stature
• Small head
• Small eyes

Diagnosis

Fanconi anemia is an inherited disease meaning it is present at birth but symptoms may not appear until much later. The condition is usually diagnosed when a child is between the ages of 2 and 15. Currently, the best diagnostic tool is a chromosome breakage test. For this test, blood cells are mixed with a chemical that damages DNA. Normal cells curtail the damage. But cells from a child.

Other tests a doctor may order include:

• A complete blood count (or CBC) to measure the number, size, and health of red blood cells, white blood cells and platelets.
• A reticulocyte count to see if the bone marrow is making red blood cells at a healthy rate.
• A bone marrow biopsy during which a small amount of bone marrow is drawn and tested.

Treatment

Like many conditions, the treatment varies depending on severity. Some children with mild forms of Fanconi anemia simply require routine check-ups and blood work. For children with more severe conditions, drug therapy can boost blood counts in the short-term.

Long-term treatment options include:

• Hematopoietic stem cell transplantation (HSCT). Currently, the standard of care, a blood and marrow stem cell transplant replaces malfunctioning cells with healthy donor cells from bone marrow, peripheral blood or cord blood.
• Androgen therapy. This approach uses synthetic hormones to goad the body into making more red blood cells and platelets.
• Synthetic growth factors. These are man-made substances that mimic the body's own growth factors to aid in the production of red and white blood cells. Roughly 60 percent of children with Fanconi anemia lack adequate growth hormones.