Possible reflex sympathetic dystrophy secondary to 'COVID toes'

ABSTRACT

A 51-year-old woman presented acutely to dermatology with an 8-week history of painful, purple discolouration of her toes, which started on her left foot but progressed to involve all of her toes. She was noted to have a positive COVID-19 polymerase chain reaction test after her symptoms began. There was some superficial ulceration of two of her toes. The episode lasted for 5 weeks;however, after 6 weeks her toes had flared again. No triggers were indentified;in particular, her symptoms were not related to the cold. There were no other rashes. She has a past medical history of endometriosis and gout. She takes desogestrel and allopurinol, which she had been on for 2 years. Vasculitis screen was negative. She was treated initially with clobetasol propionate and nifedipine. On follow-up 6 weeks later, the patient reported hypersensitivity of her toes, with severe pain reported from socks rubbing against her toes. The toes had normal appearances and cool peripheries. We suspect that the increased sensitivity and pain is a reflex sympathetic response secondary to 'COVID toes' and have treated with it gabapentin. It is thought that reflex sympathetic dystrophy occurs because inflammation causes damage to the nerves;however, the exact mechanism behind reflex sympathetic dystrophy is yet to be elucidated.