Baboon Syndrome Due to Clotrimazole Topical Preparation with Unusual Route of Entry

Sir, In 1984, Anderson coined the term "baboon syndrome" (BS) while publishing three cases of mercury-induced contact dermatitis.[1] BS is a form of systemic contact dermatitis (SCD) induced by metals, medications, or plant products and characterized by typical exanthema in flexural areas without any accompanying systemic symptoms. Miyahara[2] classified BS based on allergen and history of previous exposure. A 26-year-old pregnant female reported with complaints of diffuse red rash over the groin, inner thigh, buttocks, upper eyelids, neck, chest, inframammary folds, and abdomen with itching and burning sensation. The rash was localized to the groin region subsequently spreading to involve other flexures. She applied 1% clotrimazole cream in the groin region a few hours before the onset of the rash. The patient gives a history of insertion of clotrimazole pessary for vaginal discharge 2 days prior. Examination revealed a diffuse symmetrical erythematous rash with vesiculation and pustules involving the areas mentioned above along with a few perifollicular erythematous papules over the abdomen [Figure 1]. She was diagnosed clinically as a case of BS and managed with oral and topical corticosteroids. Patch test using soft paraffin as control and 1% clotrimazole cream as test revealed a strong positive international contact dermatitis research group (ICDRG) grade 2 reaction for 1% clotrimazole [Figure 2] which confirmed the diagnosis. The patient refused skin biopsy at the time of the acute episode and rechallenge was not advised in view of antenatal case (ANC) status.Figure 1: (a and b) Diffuse bilaterally symmetrical erythematous rash with vesiculation and pustules involving perineum, inner side of thighs, buttocks, inframammary folds, (c and d) Perifollicular erythematous papules over chest and abdomenFigure 2: (a) Patch test showing strong positive reaction of international contact dermatitis research group (ICDRG) grade II to 1% clotrimazole cream, (b) Dermoscopy of patch test showing vesicles on erythematous baseBS is benign dermatitis characterized by a symmetric erythematous rash involving the buttocks, groin, and anogenital region. The rash can be maculopapular, vesicular, pustular, or rarely bullous.[3] BS is a type IV hypersensitivity reaction with the role of sensitized T lymphocytes as evidenced by a positive patch test. BS is a form of allergic contact dermatitis syndrome (ACDS). Lachapelle[4] subclassified ACDS: localized ACDS (stage 1), regional dissemination of ACDS through lymphatic vessels (stage 2), hematogenous dissemination of ACDS to distance sites (stage 3A) or systemic reactivation of ACDS (stage 3B). Stage 3A requires sensitization by topical application as in our case whereas stage 3B can be elicited by the systemic route of allergen entry. Özkaya reported that the pathomechanism of BS involves type IVa (reaction with Th1 cells and macrophages) and IVc (reaction with cytotoxic CD8 T cells) reactions.[5] The novel "p-i" concept indicates that there is no previous sensitization required to have SCD and this concept forms the basis of the pathogenesis of symmetric drug-related intertriginous and flexural exanthem (SDRIFE).[4] In our case, the initial sensitization occurred due to clotrimazole absorbed systemically by transmucosal route followed by the elicitation phase by topical cream resulting in an eruption of rash. This case is unique in the sense that the initial sensitization phase was initiated by transmucosal absorption of medicament followed by elicitation by topical cream. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.