Hogweed dermatitis in Child
Preceding the skin lesions, the patient may experience a burning sensation of the skin. This is followed by erythema, edema, and vesicle formation within 24 hours of contact with the hogweed sap. If severe, in addition to the skin lesions, patients experience headaches and generalized fatigue. They may also complain of feeling hot.
Because phytophotodermatitis is a phototoxic reaction in which there is no immunological response, prior sensitization is not required. This type of photodermatitis is usually followed by hyperpigmentation.
Symptoms usually develop within 24-48 hours following contact with the sap and sunlight exposure.
Patients may continue to have symptoms such as pain, fatigue, and photosensitivity for up to a month after the initial plant contact.
Activities that predispose to sap exposure include gardening, hiking, bike riding, or when children use the large, hollow stem for play purposes. Pets, especially dogs, commonly acquire sap on their fur, which is subsequently transferred to the pet owner. Also, farmers and fieldworkers may inadvertently be exposed to the plant.
Of note, exposure to the plant sap of wild parsnip (Pastinaca sativa; "poison parsnip") can also cause severe phytophotodermatitis. It is frequently found in road ditches and fields, and exposure has occurred while hiking or biking along trails and gardening (pulling weeds). When in bloom it looks similar to Queen Anne's lace or dill plant and grows to around 4 feet tall. It is common throughout the United States.
L24.7 – Irritant contact dermatitis due to plants, except food
402579004 – Irritant contact dermatitis due to plant
Differential Diagnosis & Pitfalls