Indirect Coombs Test (ICT)

The Indirect Coombs Test (also known as the Indirect Antiglobulin Test or IAT) is a crucial blood test used to detect unbound antibodies floating freely in the recipient serum. While the Direct Coombs test looks for antibodies already stuck to red blood cells, the Indirect version is proactive—it checks if your blood is primed to attack certain foreign red blood cells.