Case of granuloma annulare after using tocilizumab

Granulomatous Cutaneous Drug Eruptions: A Systematic Review

BACKGROUND

Granulomatous drug eruptions are rare entities, where granuloma formation occurs as an attempt to contain an exogenous or endogenous inciting agent. Granulomatous drug eruptions may be localized to the skin or may include major systemic involvement, and their characteristics depend both on the properties of the causative irritant and host factors. Because of the overlapping features amongst noninfectious granulomatous diseases, granulomatous drug eruptions are challenging to diagnose and distinguish both histologically and clinically.

OBJECTIVE

The objective of this article is to provide a review and summary of the current literature on the five major types of cutaneous granulomatous drug eruptions: interstitial granulomatous drug reaction, drug-induced accelerated rheumatoid nodulosis, drug-induced granuloma annulare, drug-induced sarcoidosis, and miscellaneous presentations.

METHODS

A systematic review was conducted through PubMed using the search terms "granulomatous drug eruption" and "cutaneous" or "skin". English full-text studies that included human subjects experiencing a cutaneous reaction comprising granulomatous inflammation as the direct result of a drug were included. Of 205 studies identified, 48 articles were selected after a full-text review. Evidence was evaluated using the Tool for evaluating the methodological quality of case reports and case series.

RESULTS

Polypharmacy and a prolonged lag period from drug ingestion to rash onset may create diagnostic challenges. Ruling out tuberculosis is imperative in the endemic setting, particularly where anti-tumor necrosis factor therapy is the presumed cause. Interstitial granulomatous drug reactions and granuloma annulare are often localized to the skin whereas accelerated rheumatoid nodulosis and sarcoidosis may sometimes be associated with systemic features as well. Granulomatous drug eruptions typically resolve on discontinuing the offending medication; however, the decision for drug cessation is dependent on a risk-benefit assessment. In some situations, supplementation of an additional agent to suppress the reaction may resolve symptoms. In some cases, granulomatous drug eruptions may be pivotal in the successful outcome of the drug, as in cases of melanoma treatment. In all situations, the decision to continue or withdraw the drug should be carefully based on the severity of the eruption, necessity of continuing the drug, and availability of a suitable alternative.

CONCLUSIONS

Granulomatous drug eruptions should always be considered in the differential diagnosis of noninfectious granulomatous diseases of the skin. Further research examining dose-response relationships and the recurrence of granulomatous drug eruptions on the rechallenge of offending agents is required. Increased awareness of granulomatous drug eruption types is important, especially with continuous development of new anti-cancer agents that may induce these reactions.

CLINICAL TRIAL REGISTRATION

PROSPERO registration number CRD42020157009.

Tocilizumab and its usage for skin diseases

The monoclonal anti-IL6 receptor antibody called Tocilizumab is widely used by rheumatologists for joint diseases. Its application in dermatology has mainly concerned scleroderma and Systemic Sclerosis in the last years. The most varied skin diseases treated with tocilizumab, such as psoriasis, psoriatic arthritis, Behcet's Syndrome, Lupus, and the already mentioned scleroderma up to multi-organ syndromes with skin involvement will be discussed. At the same time, there have been several side reactions to the drug involving the skin forcing careful skin monitoring during treatment. Despite the evidence currently available in the appropriate literature, there is no formal recommendation for any of these diseases to use Tocilizumab for therapeutic purposes. The aim of this review was to collect all the main evidence on the use and involvement of the drug in dermatological practice in order to stimulate further research or hypothesize on possible therapeutic options.

Interstitial granulomatous dermatitis following tocilizumab, a paradoxical reaction?

Interstitial granulomatous dermatitis (IGD) is a rare dermatosis generally seen in the setting of rheumatic diseases, but also hematological disorders, internal malignances, infections, or drug induced. Herein, we report an exceptional case of an IGD with a clear chronological association with tocilizumab onset and cessation in a patient with adult-onset Still's disease. We review the granulomatous cutaneous reactions so far reported with this novel therapy: sarcoidosis, granuloma annulare, and IGD. Tocilizumab is a humanized anti-interleukin 6 receptor monoclonal antibody useful for the treatment of various systemic inflammatory disorders. Lately, it has found useful also for granulomatous diseases such as giant cell arteritis and even a promising response in IGD. Therefore, we believe our case adds the possibility of an IGD presenting as a paradoxical reaction.