Hiker's feet is a nonspecific term for a variety of conditions affecting the feet of hikers, typically associated with wearing a boot. Similar findings can be seen in other people exercising.
Risk factors:
(1) hot weather
(2) prolonged or strenuous hiking
(3) mild pedal edema
(4) chronic venous disease
(5) age over 50 years (? senile purpura)
Clinical features:
(1) purpura
(2) affect the skin of the feet and lower legs
(3) may spare areas under compression socks or stockings
(4) may be asymptomatic, pruritic, burning or painful
(5) absence of skin lesions elsewhere
(6) absence of systemic symptoms or arthritis
(7) absence of thrombocytopenia, coagulopathy or autoantibodies
(8) resolves spontaneously within 2 weeks
A skin biopsy may show leukocytoclastic vasculitis.
Differential diagnosis:
(1) heat eruption
(2) dermatophyte infection
(3) cellulitis
(4) contact dermatitis, including poison ivy or poison oak
(5) systemic vasculitis (anti-synthetase syndrome, other)
