Best Tx for cellulitis of the lower leg
What’s the best strategy to treat cellulitis of the lower leg aggravated by venous stasis? MUNIR NATHOO, MD, Whitby, ON
Chronic venous insufficiency due to valvular incompetence leads to a chain reaction of physiologic changes in the skin and upper dermis. Congestion of the superficial lymphatic system and fibrin cuffing of the capillaries causes low oxygen tension and secondary erythema of the lower extremity. This kind of erythema can be confusing, as infectious cellulitis and contact dermatitis may present with a similar clinical picture.
The lymphedema and venous backflow are the primary cause for the dermatitis. Compression of the lower limb will milk out the lymphedema and minimize the backflow. As a result, the tissue will rapidly decongest, with improvement of the circulation and colour of the leg. Before applying compression, make sure to check the quality of the arterial circulation by doing an ankle-brachial index.
The pitting edema created by the lymphatic congestion can create an environment that supports bacterial growth, especially if there are breaks in the skin that may permit bacteria into the dermis. Bacterial infection would produce pro-inflammatory mediators and an immune response such as elevated white blood cell counts and neutrophilia. Pain or other features of toxemia, though, may not always be present. If you’re not sure whether the dermatitis may be infectious, it’s prudent to consider a broad-spectrum antibiotic. But if you don’t see significant improvement after 4-5 days, the antibiotic may be discontinued.