Hidradenitis suppurativa (HS): An unrecognized paradoxical effect of biologic agents (BA) used in chronic inflammatory diseases

BACKGROUND

Paradoxical hidradenitis suppurativa (HS) induced by biologic agents (BA) is scarcely reported.

OBJECTIVE

We sought to describe the clinical characteristics and outcome of patients developing paradoxical HS under BA.

METHODS

This was a multicenter nationwide retrospective study asking physicians to report all cases of HS, confirmed by a dermatologist, occurring during treatment of an inflammatory disease by a BA.

RESULTS

We included 25 patients (15 inflammatory rheumatism, 9 Crohn's disease, 1 psoriasis) treated by 5 BA (adalimumab = 12, infliximab = 6, etanercept = 4, rituximab = 2, tocilizumab = 1). Median duration of BA exposure before HS onset was 12 (range 1-120) months. Patients were mostly Hurley stage I (n = 13) or II (n = 11). Simultaneously to HS or within 1 year, 11 patients developed additional inflammatory diseases, including paradoxical reactions (psoriasis = 9, Crohn's disease = 3, alopecia areata = 1, erythema elevatum diutinum = 1). Complete improvement of HS was more frequently obtained after BA discontinuation or switch (n = 6/10, 60%) rather than maintenance (n = 1/14, 7%). Reintroducing the same BA resulted in HS relapse in 3 of 3 patients.

LIMITATIONS

Retrospective nature and lack of complete follow-up for some patients are limitations.

CONCLUSION

HS is a rare paradoxical adverse effect of BA, but fortuitous association cannot be excluded in some cases. We observed a trend toward better outcome when the BA was discontinued or switched.

Efficacy of switching between tumor necrosis factor-alfa inhibitors in psoriasis: results from the Italian Psocare registry

BACKGROUND

Some studies have shown that switching patients from one tumor necrosis factor (TNF)-alfa inhibitor to another may be beneficial when they have an inadequate response or an adverse event.

OBJECTIVE

We sought to assess the variables predicting the efficacy of the second TNF-alfa inhibitor in patients discontinuing the first TNF-alfa inhibitor.

METHODS

Data from all 5423 consecutive patients starting TNF-alfa inhibitor therapy for psoriasis between September 2005 and September 2010 who were included in the Italian Psocare registry were analyzed.

RESULTS

In 105 patients who switched to a second TNF-alfa inhibitor who had complete follow-up data, 75% improvement in the Psoriasis Area Severity Index score (PASI 75) was reached by 29% after 16 weeks and by 45.6% after 24 weeks. Patients who switched because of secondary loss of efficacy (loss of initial PASI 75 response) or adverse events/intolerance were more likely to reach PASI 75 than those who switched as a result of primary inefficacy (PASI 75 never achieved) (hazard ratio 2.7, 95% confidence interval 1.3-5.5 vs hazard ratio 2.0, 95% confidence interval 1.0-3.9 and 1, respectively).

LIMITATIONS

There was a small number of patients with complete follow-up data.

CONCLUSION

PASI 75 response in patients who switched from one anti-TNF-alfa agent to another was significantly reduced in patients who showed primary inefficacy of the first anti-TNF-alfa.