more red blood cells in response to anemia. A rise in the retic count can mean that an infant may not need additional transfusions. Low retic is observed in infants treated with IUT and in those with HDN from anti-Kell. Neutrophils – as neutropenia is one of the complications of HDN, the neutrophil count should be checked. Thrombocytes - as thrombocytopenia is one of the complications of HDN, the thrombocyte count should be checked. Bilirubin should be tested from cord blood. Ferritin – because most infants affected by HDN have iron overload, a ferritin must be run before giving the infant any additional iron. Newborn Screening Tests – Transfusion with donor blood during pregnancy or shortly after birth can affect the results of the Newborn Screening Tests. It is recommended to wait and retest 10–12 months after last transfusion. In some cases, DNA testing from saliva can be used to rule out certain conditions. Treatment After birth, treatment depends on the severity of the condition, but could include temperature stabilization and monitoring, phototherapy, transfusion with compatible packed red blood, exchange transfusion, sodium bicarbonate for correction of acidosis and/or assisted ventilation. Phototherapy – Exposure to ultraviolet light (phototherapy) is recommended when the cord bilirubin is 3 or higher. Some doctors use it at lower levels while awaiting lab results. This converts unconjugated bilirubin to an conjugated form that is easier for the infant to clear. IVIG - IVIG has been used to successfully treat many cases of HDN. It has been used not only on anti-D, but on anti-E as well. IVIG can be used to reduce the need for exchange transfusion and to shorten the length of phototherapy. The AAP recommends "In isoimmune hemolytic disease, administration of intravenousγ-globulin (0.5-1 g/kg over 2 hours) is recommended if the TSB (total serum bilirubin) is rising despite intensive phototherapy or the TSB level is within 2 to 3 mg/dL (34–51 μmol/L) of the exchange level. If necessary, this dose can be repeated in 12 hours (evidence quality B: benefits exceed harms). Intravenous γ-globulin has been shown to reduce the need for exchange transfusions in Rh and ABO hemolytic disease." Exchange transfusion – Exchange transfusion is used when bilirubin reaches either the high or medium risk lines on the nonogram provided by the American Academy of Pediatrics (Figure 4). Cord bilirubin >4 is also indicative of the need for exchange transfusion. Transfusion reactions Once