Janus Kinase Inhibitors' Effect on Patch Testing: A Systematic Review.

Area of Science:

• Dermatology
• Immunology
• Pharmacology

Background:

• Janus Kinase (JAK) inhibitors are increasingly approved for dermatologic conditions like atopic dermatitis and psoriasis.
• Patients with these conditions have higher rates of allergic contact dermatitis (ACD), traditionally diagnosed by patch testing.
• The impact of JAK inhibitors on patch testing accuracy is not well understood.

Purpose of the Study:

• To review the existing literature on the effect of Janus Kinase (JAK) inhibitors on cutaneous patch testing results.
• To assess how JAK inhibitor use influences the diagnosis of allergic contact dermatitis (ACD) in dermatologic patients.

Main Methods:

• A systematic literature search was conducted across major databases (MEDLINE, Embase, Cochrane, Web of Science).
• Eight relevant studies were included after screening and exclusion criteria were applied.
• Data on patient demographics, dermatologic conditions, JAK inhibitors used, and patch testing outcomes were extracted.

Main Results:

• The majority of patients (88.5%) had concurrent atopic dermatitis (AD) and were evaluated for ACD.
• Upadacitinib was the most studied JAK inhibitor (60.0%).
• A significant proportion of patients (71.9%) showed negative patch test results while on JAK inhibitors, and 28.1% had reduced positive reactions.

Conclusions:

• Concurrent use of Janus Kinase (JAK) inhibitors appears to diminish patch testing readings for allergic contact dermatitis (ACD).
• This potential reduction in reactivity necessitates careful interpretation of patch test results in patients using JAK inhibitors.
• Further research is needed to fully elucidate the clinical implications of JAK inhibitor use on diagnostic testing for allergic conditions.