A clinical case-report of cutaneous vasculitis associated with exposure to paraquat

Abstract

Paraquat is a toxic herbicide frequently used in Portugal against weeds. Voluntary ingestion
is almost always synonymous with death from pulmonary fibrosis. Nevertheless, farmers who
fail to follow safety precautions, may suffer accidental intoxication via the skin or respiratory
tract. Poisoning in these cases is associated with a better prognosis.
The A.A. describe the case of a 66-year old male
who sprayed his lower limbs with a paraquat
solution. Soon afterwards, he noticed erythematous macules, that over the period of a week,
evolved to papules and ulcers in the legs and
dorsum of the feet. Two months after paraquat exposure he developed macules, papules and
haemorrhagic bullae, some of which progressed to necrosis, in the digits of the hands and
feet, associated with fever and a general sense
of being unwell. Histology revealed a small vessel necrotising vasculitis. There was a marked
improvement with steroid therapy and the patient is asymptomatic at 24-months follow-up.
After exclusion of other causes of small vessel necrotizing vasculitis and even though it was
not possible to determine the presence of paraquat in the affected skin, the temporal relationship with the direct exposure to the product allows for the hypothesis that this is a case of
hypersensitivity vasculitis caused by paraquat.
A literature search failed to reveal a previous report of such an association.