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Start with the first panel cell where you have negatives in all the phases tested. Use the cells where patient reactions are negative in all phases tested for rule outs. Look at the screen cell antigram to see which cells the patient reacted with. You may use a screen cell as a rule out cell if there were no reactions in any of the phases tested and if it is homozygous for the antibodies you are trying to rule out; antigens should be in their homozygous state in order to rule out. Refer to the screen cell antigram example below to see homozygous screen cell that can be used for rule outs. Write down what you could not completely rule out with 3 homozygous cell reactions. If Jkb is the suspected antibody, then reactions with screen cell I should be negative. This screen cell may be used as a rule out cell.

Antibody panel resultsResults of the antibody panel show reactions at immediate spin and AHG with varying strengths. The pattern at IS matches P1. Remember that varied strengths can mean multiple antibodies, dosage or both.There are not enough rule-out cells to rule anything out with 3 negative reactions. You can use panel cells that reacted at IS and are negative at AHG for rule-out. Use cells 4 and 10 for rule-outs. Antibodies that have no rule-outs from this panel are: C, E, Cw, Kpa, Jsa, Fya, Lea, M,s, P1, and Lua. Cw, Kpa, Jsa, and Lua are usually not present on panels and fall under the "unable to rule out" catagory. C,E, Fya and s are clinically siginificant and should have further testing done to rule-out or rule-in these antibodies. Lea , P1 and M tend to react at IS, so if the pattern of reactivity is compared to the reaction pattern at IS, there is a match for P1.A selected cell panel was then performed.

For electrophoretic separation of solutes, the sample of solutes is placed on a gel or membrane in contact with buffer for separation. Common gels are cellulose acetate, agarose, and polyacrylamide gels. These gels are formed into sheets, slabs, or inserted into columns or tubes. The gel can be positioned horizontally or vertically.Cellulose is chemically reacted with acetic anyhdride to form a cellulose acetate gel. Because cellulose requires soaking before sample application and a clearing step for detection of separated solutes or bands, agarose gel is more often used than cellulose acetate gel for clinical electrophoresis.

Serum iron (SI) is a measure of circulating iron bound to transferrin and is reflective of total body iron. SI is elevated in hereditary hemochromatosis (HH) and acute hepatitis. SI is decreased in iron deficiency anemia and chronic inflammation. SI concentrations exhibit diurnal variation, with the lowest values occurring around midnight. In addition, specimens collected from the same individual at the same time of the day may exhibit day to day variations as high as 40%. SI determinations are also affected by diet, menstrual cycle, pregnancy, ingestion of iron supplements, and oral contraceptive use. SI levels alone are considered insensitive indicators of HH. SI is typically measured on automated analyzers using spectrophotometric methods. Iron in the sample is released from transferrin with an acid reagent, reduced to the ferrous state, and reacted with a chromogen such as bathophenanthroline or ferrozine. The intensity of the color change is proportional to the iron concentration. Interference can arise from the use of a hemolyzed sample and contamination of reagents and water with iron. A typical reference interval for SI is 60 - 150 micrograms/dL. SI is usually ordered along with its companion test, the total iron binding capacity (TIBC), or with transferrin (Tf).(2)

3. Do the results of the initial antibody screen support the presence of the identified antibody?No: All 3 screen cells reacted in the initial screen. Upon review, however, only Screen Cells 1 and 3 were Jk(a+); Screen Cell 2 reacted but was Jk(a-).This anomalous result was investigated by a reference laboratory. It was discovered that the patient had anti-Rd, an antibody to the low frequency antigen Radin (Rd). By chance, Screen Cell 2 was Rd-positive. Radin has a frequency of less than 0.5% in several populations tested. The screen cell manufacturer was notified. They would likely confirm that the cell was Rd-positive, make their clients aware of it, and document it in future antigrams.

This CaseWith the panel done 2 weeks post-transfusion, 5 panel cells that were Jk(a+) reacted and 5 that were Jk(a-) did not. This yields a p value of 0.004, which is less than the standard of 0.05, and therefore is more than acceptable statistically. In other words, an antibody other than anti-Jka would be expected to produce these panel results only 4 times in 1000 (which is pretty unlikely).Th true p value is much lower because many more cells were tested than in the panel alone.Concluding that the antibody is anti-Jka is further strengthened because the patient's red cells type as Jk(a-).Learning points: The most important things to know about statistical tools such as p values are that they Relate to the probability of getting the observed results if the null hypothesis were true (the panel results were due to another antibody) Do not substitute for technical and clinical judgment.

The antibody in the pretransfusion specimen (prior to the patient being transfused with two units of unmatched group O Rh-negative RBC) reacted 2+ and 3+ with antibody screen and donor cells.If Jk(a+), the transfused donor RBC would have stimulated increased antibody production and the patient's plasma would be expected to react even more strongly with Jk(a+) red cells than in the pretransfusion specimen.However, the expected increase in antibody strength did not happen. Because Jk(a+) donor cells "mop up" (adsorb) the patient's anti-Jka, initially the anti-Jka decreased in strength. Later, once donor red blood cells are no longer present to adsorb the antibody, the anti-Jka would be expected to become stronger.Currently, (2-weeks post-transfusion) the patient's plasma is only reacting 1+ with Jk(a+b-) RBC and w+ with Jk(a+b+) RBC.This effect is called dosage. Learning points When a secondary immune response occurs, antibody first decreases before it increases. The expected increase in antibody strength will vary depending on the amount of excess antibody available in the patient's plasma at the time of testing versus the amount that had adsorbed to donor rbc and been removed by EVH.~