AHG must be added to the cells immediately following washing. Antibodies may elute from the cells if the cells are allowed to sit in saline without the addition of AHG.

Which one of the following may cause a FALSE-NEGATIVE result with antiglobulin techniques?

Following an accidental needlestick, the person should be tested for all of the following except:

1+ reaction has numerous small clumps and cloudy red supernatant

2+ has many medium-sized clumps and clear supernatant.

3+ has several large clumps and clear supernatant

4+ has one solid clump, no free cells, and clear supernatant

BB

Tube-based agglutination reactions in blood bank are graded from negative (0) to 4+. A reaction that has numerous small clumps in a cloudy, red background is:

In Rouleaux, red blood cells appear as stacked coins - formation occurs as the result of elevated globulins or fibrinogen.

The RBCs indicated by the arrows in this illustration are the result of:

No HLA matching is performed for corneal tissue transplants as the cornea occupies a privileged site not usually seen by the immune system. This term has been coined " immune privileged " .

Corneal tissue may be transplanted successfully from one patient to another because:

The presence of a clot is acceptable in:

Infection early in the pregnancy is the most dangerous time period for the manifestation of anomalies due to rubella. In fact, defects are rare when infection occurs after 20 weeks gestation.

Immunology

The greatest risk for the manifestation of anomalies in maternal rubella infection during gestation is the:

The difference between glass and plastic red stopper tubes is that the:

Question options:

These are tyrosine crystals

Urinalysis & Other Body Fluids

True or false? Cystine crystals are present on this slide.

HbA1C is the recommended test for monitoring diabetic carbohydrate management. Microalbuminuria, low concentrations of urinary albumin, is measured to detect early renal impairment, at a stage where it is reversible with treatment.

What is the role of microalbuminuria testing?

Amniotic fluid bilirubin is increased in association with the severity of hemolytic diseases of the newborn. As red blood cells lyse during these conditions, bilirubin builds up as a byproduct of the red cell destruction. The more red blood cells that are being destroyed in the baby, the more increased the bilirubin level will become.

Which one of the following tests BEST correlates with the severity of hemolytic disease of the newborn (HDN).

Gram positive organisms resist decolorization by ethyl alcohol. The large crystal violet-iodine complex is not able to penetrate the peptidoglycan layer, and is trapped within the cell in gram-positive organisms. Conversely, the outer membrane of gram-negative organisms is degraded and the thinner peptidoglycan layer of gram-negative cells is unable to retain the crystal violet-iodine complex and the color is lost.

What is the purpose of using ethyl alcohol or acetone in the gram stain procedure:

Phase of reactivity is primarily at immediate spin (4+) and reactions get weaker at AHG (w+). There is no specific pattern of reactivity and the auto control is negative which rules out an autoantibody. This is a strong cold antibody which is still slightly present after incubation and washing.

Activation and binding of the antibody takes place at room temperature or colder. Eliminating this phase will prevent the antibody from binding. Cold antibodies usually are more of a nuisance to blood bankers and are not clinically significant.

When performing an antibody screen, both the screen cells are 4+ at immediate spin and W+ at AHG. The antibody panel shows 4+ reactions at immediate spin and W+ reactions at AHG and there is no specific match to the reaction pattern. The auto control is negative. What would be a logical next step?

Donor and recipient blood samples (samples utilized for pre-transfusion compatibility testing) must be kept for at least 7 days after transfusion. Blood samples must be available to investigate a transfusion reaction, if necessary.

Donor and recipient blood samples must be kept for at least how long after transfusion?

Match each of the following definitions associated with heart disease and heart failure to the term that it defines.

1. Congestive heart failure

2. Infarction

3. Ischemia

4. Angina