Cutaneous Granulomas Associated With Interferon Therapy

Mycobacterium welchii Vaccine Granuloma - A Cautionary Tale

BACKGROUND

Mycobacterium welchii (Mycobacterium w) vaccine was one of the many strategies used to both treat and prevent coronavirus disease 2019 (COVID-19) infection. We report the results of a retrospective analysis of 15 cases with vaccine-site granulomas after administration of prophylactic Mycobacterium w vaccine as part of a trial for COVID-19 and our experience in managing those cases.

METHODS

This was a retrospective analysis of 15 patients with vaccine-site granulomas who were given the vaccine as a prophylactic measure as part of a trial with informed consent.

RESULTS

The mean average age of cases was 37 and the male-to-female ratio was 1:0.87. All of the patients developed erythematous tender nodules over the injection sites within a month of receiving the inoculations. Mycobacterial cultures and cartridge-based nucleic acid amplification tests yielded negative results. Skin biopsy revealed granulomatous dermatitis with acid-fast bacilli positivity. A diagnosis of noninfective granulomatous dermatitis was made. Treatment started with analgesics and anti-inflammatory agents. Systemic antibiotics were required in 9/15 patients. Patients are being followed up with no reported recurrence till date.

CONCLUSION

The possibility of injection-site granuloma should be taken into the risk-benefit analysis for the administration of Mycobacterium w vaccine and the patients should be counseled as such. Patients with persistent ulceration respond to combinations of doxycycline, ofloxacin, and clarithromycin.

Cutaneous granulomas associated with rubella virus: A clinical review

Since the initial identification of vaccine-derived rubella virus (RuV) in the cutaneous granulomas of pediatric patients with inborn errors of immunity in 2014, more than 80 cases of RuV granulomas have been reported implicating both vaccine-derived and wild type RuV. Previously thought to arise exclusively in patients with significant immunocompromise, the identification of RuV granulomas in clinically immunocompetent patients adds nuance to our understanding of the interplay between host environment, immune dysregulation, and RuV granuloma formation. This review summarizes the literature on RuV granulomas including clinical and histopathologic features, proposed pathomechanisms supporting granuloma development, and potential therapeutic options. There is no standardized algorithm to guide the workup and diagnosis of suspected RuV granulomas. We highlight the importance of contributing RuV granuloma cases to ongoing Centers for Disease Control and Prevention surveillance efforts to monitor wild type and vaccine-derived RuV transmission. Studies advancing our understanding of RuV granulomas may provide insights into the role of viral infectious agents in granulomatous disease pathogenesis and guide the development of improved therapeutic options.

Current concepts in granulomatous immune responses

Persistent irritants that are resistant to innate and cognate immunity induce granulomas. These macrophage-dominated lesions that partially isolate the healthy tissue from the irritant and the irritant induced inflammation. Particles, toxins, autoantigens and infectious agents can induce granulomas. The corresponding lesions can be protective for the host but they can also cause damage and such damage has been associated with the pathology of more than a hundred human diseases. Recently, multiple molecular mechanisms underlying how normal macrophages transform into granuloma-inducing macrophages have been discovered and new information has been gathered, indicating how these lesions are initiated, spread and regulated. In this review, differences between the innate and cognate granuloma pathways are discussed by summarizing how the dendritic cell - T cell axis changes granulomatous immunity. Granuloma lesions are highly dynamic and depend on continuous cell replacement. This feature provides new therapeutic approaches to treat granulomatous diseases.

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.