In vitro release of interferon-gamma from peripheral blood lymphocytes in cutaneous adverse drug reactions.
BACKGROUND
Cutaneous drug reactions are common but diagnostically challenging due to phenotypic heterogeneity and simultaneous exposure to multiple drugs. These limitations prompted the development of diagnostic tests.


OBJECTIVE
To evaluate the performance of an in vitro assay measuring interferon-gamma release from patients' lymphocytes in the presence of causative drugs for the diagnosis of drug reactions.


METHODS
Mononuclear cells derived from patients were incubated with and without suspected drugs, and increment of interferon-gamma levels was measured by ELISA. We performed a telephonic survey to evaluate the effect of stopping the drugs incriminated by the assay on cutaneous manifestations.


RESULTS
We assessed 272 patients who used 1035 medications. When assessed against the questionnaire data collected at least 6 months after stopping the causative drug, sensitivity was found to be 83.61% and specificity 92.67%. Likelihood ratio for a positive test is 11.40 and for a negative test 0.18. Positive predictive value is 75.37% and negative predictive value is 95.47%. The test was found to perform significantly better in females and in older patients.


CONCLUSIONS
Interferon-gamma release test is a useful adjunct tool in the diagnosis of cutaneous drug reactions.
Department of Dermatology, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 64239, Israel. ilangoldberg1@gmail.com
Ilan
I
Goldberg
Meital
M
Hanson
Gabriel
G
Chodick
Idit
I
Shirazi
Sarah
S
Brenner
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D003875:Drug Eruptions / Q000175:diagnosis* / Q000276:immunology; D005076:Exanthema / Q000139:chemically induced / Q000276:immunology; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D059425:Interferon-gamma Release Tests; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D012737:Sex Factors; D055815:Young Adult
D007371:Interferon-gamma