Transfusion Reactions

This week in lab we combined elements of two of the classes we are taking this semester: Blood Bank and Infectious Disease.  I felt that the exercise also brought together several things we have learned since beginning the program.  We processed simulated samples from patients that were experiencing a transfusion reaction.  These reactions can occur for several reasons including factors with the recipient’s immune system and contamination of the blood product itself. 

The process of determining what could be responsible for a transfusion reaction began with reviewing the patient’s vital signs and symptoms, looking for clerical errors, processing several laboratory tests on the individual’s blood and urine, and finally setting up microbiological testing  from the donor material to see if a microbial organism was growing in the product itself.



The blood product that was being transfused in our case was a unit of platelets, which have the highest rate of contamination since they are incubated at room temperature up to five days.

The first step to analyzing the microbiological aspect of the laboratory was utilizing a Gram Stain to get an idea whether any organisms were present and a preliminary identification of those that were observed. The appropriate media for growth of the specimen included Sheep Blood Agar, MacConkey, Chocolate, and a time saving special plate that differentiates organisms by causing colonies of various species to appear specific colors thus saving time in the determination of the causative microbe.

When observing the Gram Stain of my specimen I noticed many Gram positive organisms with elongated protrusions growing out of their sides, which are known as germ tubes.  This led me to believe that the specimen had become contaminated by a Candida species yeast organism.  After 24 hours, I was able to observe the different media plates that were set up and determine that it was the Candida albicans species, based off its color on the specialty media that differentiated organisms of the Candida genus by the color of the colony growth.

As I stated before, I thought this laboratory exercise brought together several aspects of the program we have learned about so far, and was a good simulation of a real world circumstance.