Table 2.

Pros and cons of in vitro tests available for idiosyncratic drug reactions

	Detection of drug-specific
	IgEs	LTT	LTA	BAT	iPTA
Pros	The test has high positive predictive value. Positive results are highly suggestive of type I immune-mediated reaction.	The test has been used for a long time and has accumulated a reasonable amount of clinical experience. Positive result demonstrates the involvement of the immune system in the reaction pathophysiology.	A reasonable experience with clinical use is available. In principle the test can be used to predict potential risk to develop a reaction prior to exposure as it detects phenotypic predisposition.	Recent adaptations of flow cytometric methods have increased its sensitivity. New techniques allow the use of whole blood samples.	The test procedure is simplified and more reproducible. Smaller volume of blood samples is needed. Has been shown to have a higher sensitivity compared with the LTA.
Cones	Low sensitivity and negative predictive value. Traditionally the technique involves the use of radioactive reagents.	Expensive and requires highly skilled personnel and sophisticated equipment. Predictive value is not well defined.	Procedure is time consuming and demands special skills, resources and reagents. Has very limited use in few centres.	Can detect limited types of reactions, which involve basophil activation. Has low sensitivity. Available only for a limited number of drugs.	The test has not been validated by independent group.

BAT, basophil activation test; iPTA, in vitro platelet toxicity assay; LTA, lymphocyte toxicity assay; LTT, lymphocyte transformation test.