CD24 Irritant contact dermatitis from <i>Dieffenbachia schott</i>: a case report of a florid reaction to a common household plant

Abstract Dieffenbachia Schott, commonly known as dumb cane, is a popular ornamental house plant renowned for its striking foliage. The plant’s sap contains calcium oxalate crystals, which can cause irritant or allergic contact dermatitis upon direct exposure. While allergic reactions to Dieffenbachia are rare (eye symptoms and severe irritant skin allergies), the plant’s widespread domestic presence poses a significant risk, which we discuss in our case below. A 68-year-old woman who was an avid gardener was rearranging her long-standing indoor plant. During a routine tidying session, she removed two leaves barehanded, noting sap exposure on her fingers. They began to tingle. She remembers wiping the skin but not washing it. The following morning there were multiple painful blisters on the fingers between the web spaces of her right hand. Her medical history included an irritant contact allergy to hyacinth bulbs. She was given antihistamines and mild topical corticosteroids. However, symptoms worsened with larger blisters developing. Examination revealed blistering and erosions between the web spaces with an annular erythematous edge. She felt mildly unwell and a fever brewing. The C-reactive protein was mildly elevated at 12 mg L−1. The clinical impression was of an irritant contact dermatitis due to Dieffenbachia sap. Management involved oral flucloxacillin for 1 week, topical betamethasone dipropionate with clotrimazole applied twice daily for 2 weeks, potassium permanganate soaks, Dermol 500 as a soap substitute, and white soft paraffin as a moisturizer. At follow-up, the patient showed complete resolution of symptoms and significant recovery of the affected skin. Indoor plants are thought to be safe. However, this case underscores the rare presentation of a likely progressing irritant contact dermatitis from Dieffenbachia sap. We know this can affect eyesight if the sap comes in contact with the mucosa. We felt an irritant contact dermatitis was most pertinent given the severity and acute nature of the eruption and thus did not patch test her. The history of hyacinth bulb allergy may have predisposed her to a lower threshold for a reaction. We present this case for wider acknowledgement of plant eruptions and suggest that gardening gloves are a useful adjunct for handling outdoor as well as indoor plants.