Blood Transfusions Safe, Efficient for Treating Hospitalized AIHA Patients, Study Suggests
This conclusion held true even when using incompatible donors and even for the one-third of patients who developed severe anemia during hospitalization, according to the study.
The study “Autoimmune hemolytic anemia in hospitalized patients: 450 patients and their red blood cell transfusions” was published in journal Medicine.
AIHA includes two variants: cold agglutinin disease (CAD) and warm antibody autoimmune hemolytic anemia (warm AIHA). In CAD, autoantibodies bind more easily to red blood cells at lower temperatures, and in warm AIHA, at higher temperatures.
AIHA is classified as primary if there is no underlying condition and secondary if it occurs as a manifestation or complication of another disease.
In AIHA patients, low levels of red blood cells or anemia, can have a milder or more severe presentation, which often is gradually or completely replenished by the production of new red blood cells. In some cases, patients develop life-threatening anemia and need blood transfusions to rapidly restore their red blood cells and hemoglobin levels.
However, treating AIHA patients with blood transfusions can be challenging. Red blood cells from serologically compatible donors (those with the same blood type) are also recognized by the patients’ autoantibodies, further aggravating the destruction of red blood cells. Patients can also develop specific antibodies against the donor red blood cells, called alloantibodies, found in 20–40% of AIHA patients.
Researchers here assessed the clinical features of AIHA that required hospitalization, as well as the outcomes and effectiveness of treating patients with blood transfusions.
They collected data from 450 patients (315 women), median age 51 years, diagnosed with AIHA, admitted at the West China Hospital from January 2009 to December 2015. The median length of hospital stay was 17 days.
Secondary AIHA patients were generally younger than those with primary AIHA, had a higher rate for blood transfusions, and were treated more often with second-line therapy. Most (97.3%) had warm AIHA.
Anemia severity was determined by measuring the amount of hemoglobin. Patients whose levels of hemoglobin fall to 100 grams per liter (g/L) or less are considered anemic. At admission, 15 patients had hemoglobin levels below 30 g/L; 153 had 30 g/L–59.9 g/L; 206 had 60 g/L–89.9 g/L; and 76 had above 90 g/L.
Corticosteroids, a treatment that weakens the immune system, were provided to 408 (90.7%) patients. Prednisone and dexamethasone were the most commonly prescribed steroids.
Second-line treatments were given to 150 patients. These included steroid-sparing or steroid-substituting agents, splenectomy (surgical spleen removal), and Rituxan (rituximab) — a therapy used against B-cells that produce antibodies.
More than 40% of patients achieved remission; however, only 12 (2.7%) achieved a complete response, reaching a hemoglobin level above 120 g/L. During the study, 22 patients died, most from infections.
A total of 269 patients received blood transfusions in 1,112 episodes. Complete clinical data was available for 885 episodes, where only 14 were reported to lead to transfusion-related reactions. These adverse reactions included fevers (13 cases), allergies (one case), and headaches combined to elevated blood pressure (one case).
With blood transfusions, hemoglobin levels increased from an average of 52 g/L to 65.1 grams g/L. Researchers evaluated the transfusion efficiency, or the effectiveness of the transfusions, for 352 episodes, of which 58.5% were considered efficient.
In total, 157 transfusions tested positive for red blood cell antibodies, but when researchers analyzed adverse reactions from alloantibodies, they found that using less compatible donors still led to successful transfusions.
Hemoglobin levels between 40 and 50 g/L were associated with the best remission rates, according to the researchers.
These results in hospitalized AIHA patients show that “transfusions with the least incompatible blood did not adversely affect transfusion efficiency,” they said. “This is important for clinicians since there should be little delay in transfusions, should they be deemed necessary.”