[Appearance of anti-red blood cell antibodies in 80 years old and over transfused patients: result of 3 years haemovigilance survey]

Acquired red blood cell alloantibodies in transfused patients of 80 years or over: a 2008-2013 national haemovigilance survey

BACKGROUND

As transfusion in the elderly patients has increased over the last decades, and with the aim of improving blood policy, post-transfusion red blood cell alloimmunisation, a delayed serological transfusion reaction, was investigated in patients 80 years old or over.

MATERIALS AND METHODS

For every adverse reaction to a transfusion, a report is sent to the French haemovigilance database. All cases of red blood cell alloimmunisation reported in the haemovigilance database were collected, and an analysis was performed on those cases in transfused patients 80 years old or over.

RESULTS

There were 11,625 reports of red blood cell alloimmunisation from 1 January, 2008 to 31 December, 2013, of which 3,617 (31.1%) occurred in patients 80 years old or over. Among this subgroup, red blood cell concentrates were the most frequently involved blood component (3,482 reports, 96.3%). Red blood cell alloimmunisation after transfusion of platelet concentrates was also notified (132 reports, 3.7%). Anti-KEL1 was the most frequent antibody (874 reports, 24.2%). The imputability of the blood component was certain in 2,340 cases (64.7%) and probable in 1,078 (29.8%). In 2013, the incidence of red blood cell alloimmunisation was 4.14 per 1,000 transfused patients aged 80 years old or over.

DISCUSSION

In a 6-year national survey in which 40,570 reports were made, there were 3,617 cases of red blood cell alloimmunisation in transfused recipients of 80 years old or over. This delayed serological transfusion reaction is not rare. Red blood cell concentrates were predominantly involved, but cases caused by platelet concentrates were also described. In order to prevent alloimmunisation in the elderly, several factors must be evaluated before transfusing matched red blood cell concentrates: the patient's age, pathology and its outcome, the type of transfusion support (chronic or not), life expectancy, and blood product availability.

[Adverse transfusion reactions in recipients with anti-vitamin K treatment]

PURPOSE OF THE STUDY

Vitamin K antagonist treated patients are exposed to a risk of haemorrhage in case of overdose leading to a need for transfusion. In order to determine the incidence of adverse transfusion reactions in these patients, the reports indicating a vitamin K antagonist treatment were analyzed.

PATIENTS AND METHODS

In the treated and transfused patient population, the diagnosis following the adverse transfusion reactions, the incidence, the degree of severity, the blood component involved and its imputability were evaluated.

RESULTS

From January 1st 2000 to December 31st 2014, 142 reports were notified in 141 patients. Haemorrhage was observed in 102 cases (71.8%). Overdose of anti-vitamin K was reported in 43 cases only (30.3%). The most frequent adverse transfusion reaction was the anti-erythrocyte alloimmunization (66 cases, 46.5%) followed by the febrile non-haemolytic reaction (37 cases, 26.1%). Most adverse reactions were non-severe (131 cases, 92.3%). The most involved blood component was the red blood cells concentrate (139 cases, 97.9%). The imputability of the blood product was certain in 39 cases only (27.5%).

CONCLUSION

In patients treated with vitamin K antagonists and transfused, the anti-erythrocyte alloimmunization was the most frequent adverse transfusion reaction. Overdose of the vitamin K antagonists was notified in approximately a third of cases.