DHTR: Diagnosis

How to Subscribe
MLS & MLT Comprehensive CE Package
Includes 139 CE courses, most popular
$95Add to cart
Pick Your Courses
Up to 8 CE hours
$50Add to cart
Individual course$20Add to cart
The page below is a sample from the LabCE course Transfusion Reactions. Access the complete course and earn ASCLS P.A.C.E.-approved continuing education credits by subscribing online.

Learn more about Transfusion Reactions (online CE course)
DHTR: Diagnosis

The symptom most commonly associated with a DHTR is unexplained decrease in hemoglobin. Patients may also present with fever and jaundice. Hemolysis occurs slowly and is primarily extravascular. Unlike an acute hemolytic transfusion reaction (AHTR), hemoglobinuria, acute renal failure, and disseminated intravascular coagulation (DIC) are not generally seen. Many delayed reactions may go unnoticed as patients may not report the symptoms to their physicians unless the symptoms are severe.   

Serologic findings include a positive direct antiglobulin test (DAT) and/or a positive antibody screen in post-transfusion testing. In many cases, the physician will send a request for an additional transfusion because of the decreased hemoglobin levels, and not suspect a DHTR. The positive antibody screen will trigger an investigation including antibody identification. The DAT may have a mixed field appearance because of the antibody-sensitized transfused red cells and the non-sensitized patient red cells. Segments from the donor unit can be tested for the offending antigen once the antibody has been identified.

Antibodies that are most often reported as the cause of DHTR are anti-Jka and anti- Jkb. Other antibodies that are also commonly implicated in a DHTR include Kell, Rh, and Duffy system antibodies. The patient's physician should be notified so that additional clinical and laboratory evidence can be evaluated.