Diamond-Blackfan anemia (DBA)

DBA is usually found in a baby's first year. About half of babies have signs by 3 months of age. A blood count shows anemia, with red cells that are larger than normal and very few young red cells (reticulocytes). A hematologist, a doctor who treats blood diseases, then checks a bone marrow sample. In babies, this is often done later, before steroid treatment starts. In DBA, the marrow makes too few early red cells, without the abnormal-looking cells seen in some other marrow diseases.

Two more blood tests help, and they work best before the first transfusion or at least 6 weeks after the last one. One measures an enzyme called eADA, and the other measures fetal hemoglobin (HbF). A clearly high eADA strongly suggests DBA, but a normal result does not rule it out. Genetic testing, using a gene panel or exome or genome sequencing, looks for a change in a known DBA gene. RPS19 is the most common, found in about 1 in 4 people. Genetic results can take a few days to weeks.

About 20 to 30 in 100 people with DBA have no gene change found. They can still be diagnosed from their blood and marrow results. Experts also advise HLA typing of the child and family as part of the first tests. It is not part of the diagnosis, but it matters for long-term planning.

Transfusions provide functioning red cells. Iron chelation removes excess iron, with blood tests and imaging used to assess the burden. Chelation is an essential part of care when iron accumulates.

A corticosteroid trial is commonly considered after infancy. Continued use depends on response and a tolerable dose, because prolonged steroids can affect growth, bones, eyes, metabolism and infection risk. Some people need transfusions instead.

Allogeneic transplantation may be considered for significant transfusion dependence, unacceptable treatment toxicity or other serious marrow complications. Its timing depends on age, iron burden, health and available donors. It can correct the blood-cell defect but does not remove all non-blood manifestations or cancer susceptibility.

When a transplant from a donor is planned, the team usually tests brothers and sisters first. Each full sibling has about a one in four chance of being a full match.

Most patients do not have a matched relative. In the words of NMDP, the U.S. registry, “75% of patients don’t have a fully matched donor in their own family.” The team then searches registries of volunteer donors around the world and banks of donated cord blood. In some transplants, a half-matched parent, child or sibling can also be the donor.

Matching depends on inherited tissue markers called HLA, so a patient is most likely to match someone who shares their ancestry. Every person who joins makes the search a little more likely to succeed, especially for patients from groups that are underrepresented on registries.

DBA is lifelong, and its course varies a lot from person to person. An international expert consensus names the two leading causes of death in people who have not had a transplant: iron overload from transfusions, and cancer. That is why removing extra iron and regular cancer checkups matter so much.

Most people respond to steroid medicine at first. Over time, some lose the response or must stop because of side effects. About 1 in 5 people once treated with steroids or transfusions can stop all treatment for anemia (treatment independence). The genetic condition is still there, though, and anemia can return. For people who depend on transfusions, a donor transplant can cure the blood problem. In a German and French study, results were similar with a matched sibling or an unrelated donor, and survival was higher for transplants done after 1999. A transplant does not remove the higher cancer risk, so screening continues.

There is no single life-expectancy figure that fits everyone with DBA. The numbers below describe groups and cannot predict one person's future.