Cutaneous Adverse Drug Reactions with Antimalarials and Allergological Skin Tests

Abstract

Background: Currently used antimalarial drugs (AM) are hydroxychloroquine and chloroquine, which are prescribed for many autoimmune disorders. The value of skin tests on cutaneous adverse drug reactions (CADR) with AM remains unknown. Objective: The main objective of this retrospective study is to know whether skin tests for AM are useful and how to manage the recovery of AM therapy in these patients. Methods: All patients referred for suspected CADR secondary to AM between 2001 and 2014 in eight French dermatology centers were retrospectively reviewed. Results: We report herein a retrospective series of 20 patients with CADR and AM involvement. Skin tests, performed in 14/20 patients, were negative in all cases. Six patients had an oral provocation test with recurrence of CADR in 1 case. Conclusion: We encourage dermatologists to perform oral provocation tests in nonsevere CADR in order to allow AM rechallenge at progressive doses.

Early cutaneous eruptions after oral hydroxychloroquine in a lupus erythematosus patient: A case report and review of the published work

“…If the patient has only mild skin eruptions, as in the present case, the HCQ treatment may be continued. Even though HCQ has a very long half‐life at approximately 50 days and complete elimination requires more than 8 months after withdrawal of the drug, some patients, such as the present case, may continue the HCQ treatment under careful monitoring with improvements in symptoms and no complications . One possible explanation for this phenomenon is immune tolerance leading to a decrease in drug eruptions despite long‐lasting circulation …”

“…Few treatment options were provided in the previous reports in which some patients were treated with topical steroids or oral corticosteroids . The successful desensitization protocols to HCQ were also reported and may be helpful in clinical practise . Based on these observations, as shown in Figure , we suggest that dermatologists need to evaluate the condition of cutaneous eruptions and other systemic organs for decision‐making regarding the cessation of HCQ.…”

“…HCQ exerts its effects relatively slowly; it typically takes 2 or 3 months for its effectiveness to be detected and sometimes several months for maximal efficacy to be achieved . Therefore, it is sometimes difficult to establish whether early cutaneous eruptions that appear after the initiation of oral HCQ are due to HCQ or a flare of disease . Dermatologists need to distinguish these conditions and provide an appropriate solution.…”

“…The mechanisms responsible for the early occurrence of cutaneous eruptions by HCQ currently remain unknown. It may be a reactive allergic phenomenon associated with an imbalance in the immune system in an early stage after the initiation of HCQ . We summarize the characteristics of 21 reported cases of LE with cutaneous reactions due to HCQ, including our case, in Table .…”

“…Otherwise, if there is more evidence to support cutaneous reactions due to HCQ, a patient's systemic symptom needs to be carefully evaluated in order to decide whether to continue, stop then restart or stop this drug completely. Based on our review of the published work, HCQ needs to be stopped completely and another systemic therapy initiated in patients with widespread severe reactions, such as widespread skin rash and/or severe irritation, widespread acute generalize exanthema pustulosis, drug rash with eosinophilia and systemic symptoms or Stevens–Johnson syndrome/toxic epidermal necrolysis . If cutaneous eruptions are accompanied by other common reactions such as headaches, nausea, vomiting, diarrhea or stomach pain, HCQ needs to be stopped for a period of time and then restarted.…”