Reverse Blood Typing Agglutination Reaction Calculator

The Reverse Blood Typing Calculator helps determine an individual’s ABO blood group by analyzing agglutination reactions with known type A and type B red cells. This is commonly used in transfusion medicine alongside forward typing.

Historical Background

Reverse blood typing became widely used in the 20th century to confirm ABO blood group determinations. It utilizes the naturally occurring antibodies present in plasma to detect antigens on known red cells, adding a layer of verification in blood banks and clinical labs.

Calculation Principle

• If a patient's plasma agglutinates A cells → anti-A antibodies present → blood type B.
• If a patient's plasma agglutinates B cells → anti-B antibodies present → blood type A.
• If both react → has both anti-A and anti-B → blood type O.
• If neither reacts → no antibodies → blood type AB.

Example Determination

• Reaction with A cells: Agglutination
• Reaction with B cells: No Agglutination
  → The plasma contains anti-A antibodies → Blood Type B

Importance and Usage Scenarios

• Transfusion Safety: Confirms blood group compatibility to avoid fatal reactions.
• Crosschecking: Reverse typing is a backup to forward typing using red cell antigens.
• Blood Donation: Ensures correct labeling of donor and recipient units.

Common FAQs

1. What if results are mixed or unclear?

   • Retest or consult additional serological methods. Mixed-field reactions may occur in transfused patients.

2. Is Rh factor tested in reverse typing?

   • No, reverse typing is for ABO only. Rh status is checked separately via forward typing.

3. Can infants be reverse typed?

   • Not reliably. Infants under 6 months may not produce enough antibodies for accurate reverse typing.

4. What if both reactions are agglutination?

   • Indicates blood type O (has both anti-A and anti-B antibodies).

This calculator assists medical professionals and students in interpreting reverse typing results quickly and accurately.