Interstitial Granulomatous Dermatitis Induced by Simvastatin

Introduction: Reactive granulomatous dermatitis represent cutaneous reactions pattern that occur in the setting of a systemic trigger, including connective tissue diseases, arthritis, malignancy and drugs. We report a case in which an IGDR triggered by simvastatin Case report: A 68-year-old woman, with dyslipidaemia, presented with a 6 months history of skin lesions that developed after starting treatment with simvastatin. Physical examination revealed the presence of bilateral and symmetrically distributed erythematous plaques over her thighs. Histopathological findings from skin biopsy showed an interstitial predominantly lymphocytic infiltrate with mall granulomas including rare giant cells surrounding foci of collagen fragmentation. These findings were characteristic for an interstitial granulomatous drug reaction. Skin lesions resolved after discontinuation of simvastatin Discussion: Drug-induced interstitial granulomatous dermatitis was first described in 1998. In this initial description, calcium channel blockers, β-blockers, lipid-lowering agents and angiotensin –converting enzyme inhibitors were the most common offending agents. The list of culprit drugs has increased with time and include also antihistamines, diuretics, antidepressants, allopurinol, thalidomide, anti-TNF αagents, febuxostat, gabapentine, ganciclovir, Chinese herb extract, sorafenib, adalimumab, anakinra, darifenacinand soy. IGDR is probably underdiagnosed because of the variability of its cutaneous expression and a definitive diagnosis requires histological examination. The etiopathogenesis of reactive granulomatous dermatitis is unclear. Conclusions: Patients with interstitial granulomatous dermatitis should be evaluated for underlying autoimmune disease, malignancy or drug reaction and should be closely followed up. INTRODUCTION Statins, or 3-hydroxy-3-methyl-glutaryl coenzyme-A (HMG-CoA) reductase inhibitors, are among the most prescribed drugs internationally. These drugs have proved clinical benefits in hypercholesterolemia and in the primary and secondary prevention of cardiovascular and cerebrovascular events [1-3]. Statins in general have a favourable safety profile, however, several and serious systemic and dermatological side effects have been registered, such as myopathy, diabetes mellitus, hepatotoxicity, autoimmune reactions and eosinophilic fasciitis. Diverse dermatological reactions include urticaria, eczema, dermatitis, lichenoid eruptions, pemphigus erythematosus, subacute cutaneous lupus erythematosus dermatomyositis, porphyria cutanea tarda, phototoxicity, cheilitis, generalized exanthematous pustulosis, chronic actinic dermatitis, occupational contact dermatitis, bullous dermatosis and toxic epidermal necrolysis [4]. Reactive granulomatous dermatitis represent cutaneous reactions pattern that occur in the setting of a systemic trigger, including connective tissue diseases, arthritides, malignancy and drugs [5]. Interstitial granulomatous drug eruption (IGDR), is a drug induced skin disease [5-7]. We report a case triggered by simvastatin CASE REPORT: A 68-year-old woman, with personal history of allergy to nonsteroidal antiinflammatory drugs and dyslipidaemia, presented with a 6 months history of skin lesions that developed after starting treatment with simvastatin and increase of transaminases. Physical examination revealed the presence of bilateral and symmetrically distributed erythematous plaques over her thighs (Fig 1). Histopathological findings from skin biopsy showed an interstitial predominantly lymphocytic infiltrate with small granulomas including rare giant cells surrounding Rosa Gimenez-Garcia & Eva Martinez Martin ARC Journal of Dermatology Page | 15 foci of collagen fragmentation. (Fig 2) These findings were characteristic for an interstitial granulomatous drug reaction. Skin lesions resolved after discontinuation of simvastatin.