Chilblain
Idiopathic chilblain or also called acro-ischemic lesions, presenting as
violaceous, infiltrated painful and sometimes even pruritic plaques on
erythematous skin with predilection on the back of the toes or feet has
been described to occur in a special group of SARS-CoV-2 positive,
suspected patients as well as asymptomatic or non-infected patients
(Fig. 4F) (66, 67 ). Histologic features of these lesions were
typical for a lymphocytic vasculitis, with a superficial and deeper
lymphocytic infiltration around vessels and close to eccrine glands, a
papillary edema, vacuolar degeneration of the basal layer as well as
lymphocytic exocytosis to the epidermis. Red cell extravasation as well
as focal thrombosis in papillary dermal capillaries as well as vessels
of the reticular dermis were described in some reports as well
(49, 68 ). The pathologic pathways behind these lesions are
still unknown and remain to be elucidated. If it is related to
SARS-Cov-2 infection remains to be demonstrated.