ASH Updates Severe Aplastic Anemia Guidelines With 33 Evidence-Based Recommendations

In early April, the American Society of Hematology released a comprehensive set of clinical guidelines for diagnosing and treating severe acquired aplastic anemia, a rare disorder in which the bone marrow fails to produce adequate blood cells. The guidelines, published in Blood Advances, represent the work of a multidisciplinary panel that included a patient with direct experience of the disease. They contain 33 distinct recommendations and four statements on best practices, designed to standardize care across the field and improve outcomes for both children and adults living with this life-threatening condition.

Aplastic anemia strikes when bone marrow stops generating sufficient quantities of blood cells—a failure that leaves patients exposed to profound fatigue, severe infections that can turn septic without warning, and uncontrolled bleeding from even minor injuries. The disorder is not common, but it is not rare enough to ignore. Between one and two million people develop it each year in Western countries; in Asia, the annual incidence climbs to between five and seven million. Most cases arise either from an overactive immune system attacking the marrow itself or from no identifiable trigger at all. But acquired aplastic anemia—the focus of these new guidelines—develops after exposure to infections, certain medications, toxic chemicals, or other environmental hazards. The severe form is defined by extremely low counts: fewer than 500 neutrophils (infection-fighting white blood cells) per microliter of blood, fewer than 60,000 reticulocytes (immature red blood cells) per microliter, and fewer than 20,000 platelets (the cells that enable clotting) per microliter.

The new recommendations reshape how clinicians approach the disease from first suspicion through treatment. They call for expanded use of advanced diagnostic testing—specialized blood work and genetic analysis—to confirm the diagnosis with certainty and guide which treatment path makes sense for each patient. They emphasize personalized initial treatment decisions based on the patient's age and whether a fully matched bone marrow donor is available. They recommend adding eltrombopag, a drug that stimulates platelet production, to the standard immunosuppressive therapy that attempts to quiet the immune system's attack on the marrow. And they provide guidance for patients whose disease does not respond to initial treatment or returns after seeming improvement, including when to move to second-line therapies earlier than previous practice might have suggested.

Phil Scheinberg, chair of the guideline committee and head of hematology at Hospital Beneficência Portuguesa in São Paulo, emphasized that accurate diagnosis is the foundation of everything that follows. Without it, patients cannot reach the right treatment at the right time. He noted that the guidelines aim not only to improve outcomes for individual patients but also to expand access to the diagnostic testing and therapies that many parts of the world still lack. Robert Negrin, president of the American Society of Hematology, called the guidelines a robust resource for clinicians and a tool to raise awareness of a serious disorder that remains overlooked despite its severity.

The guidelines also underscore the importance of shared decision-making between patients and their doctors—a recognition that treatment choices carry real weight and that patients deserve a voice in determining their own path. At the same time, the panel acknowledged that significant gaps remain in the evidence base. They identified areas where additional research is needed to develop recommendations with higher certainty, pointing toward the ongoing work required to refine treatment strategies and expand access to proven therapies across the globe.