This patient has stasis dermatitis, and compression stockings should be used. Stasis dermatitis is characterized by red, inflamed, pitted skin on the lower legs. It occurs in patients with venous stasis disease or other causes of chronic lower extremity edema. Decreased venous drainage causes an increase in extravascular tissue fluid that results in stretching of the skin and a subsequent propensity for loss of barrier integrity. Also, because the shins are often one of the driest parts of the body and are easily excoriated, dermatitis in this area is common. Compression stockings help to increase the venous return, decrease the stretching of the skin, and reduce the risk of ulceration.

Stasis dermatitis is frequently confused with cellulitis. The four cardinal signs of cellulitis are erythema, pain, warmth, and swelling; associated lymphadenopathy can occur. Systemic symptoms, including fever, chills, and malaise, also may be present. This patient does not have fever, pain, or clinical findings consistent with cellulitis, and it is unlikely for cellulitis to present on both legs simultaneously. Compared with cellulitis, the redness on the anterior shins in patients with stasis dermatitis is often bilateral and warm to the touch but typically is not tender. Therefore oral cephalexin is not indicated.

This patient has edema related to the venous stasis but has no jugular venous distension, no crackles, and no S₃. Given the absence of volume overload, furosemide would not be indicated.

Topical mupirocin would be indicated for impetigo, but this patient has no bullae, crusts, or erosions that would be seen in impetigo.