DISCUSSION
Leg skin is unique in many respects. For one thing, it’s down there, where gravity takes and often holds blood and other fluids that might not accumulate elsewhere. It’s also a long trip for blood to get out to the extremities and often a longer return trip.
Leg skin is also remarkable because it has far fewer sebaceous glands than the scalp, face, and chest, which means it tends to be quite dry. This is especially true in older patients already prone to dry skin and in those who seldom moisturize to counteract this problem (in other words, men!).
This is why most patients with asteatotic eczema (AE) are men. Also known as eczema craquele and xerotic eczema, AE is especially common in the dry winter months, when long, hot showers are so appealing, as are wearing warmer clothes and sleeping under heavy covers.
Patients with AE, including this one, often make matters worse by applying a multiplicity of contactants. The edema noted in the exam, although due to the AE, also served to worsen the condition by making the skin tighter and drier still.
At this point, the problem often starts to take on aspects of lichen simplex chronicus, in which more scratching leads to more itching (and then more scratching, and so on). Clearly, what this patient needed (and got) was a definitive diagnosis and a treatment plan dictated by that diagnosis.
AE can be a challenge to treat, but the first step is to help the patient understand the nature of the problem and his role in the solution. The patient also needs to stop applying nonprescribed/recommended contactants, which don’t help and may exacerbate the problem.
To achieve relief, the patient can soak the leg with wet compresses for 10 minutes, remove excess water, and then apply a medium-strength steroid ointment (eg, triamcinolone 0.5%) in a thin but thorough coat. The area can then be covered with an occlusive covering, such as saran wrap, taped in place. This should be left on all night. During the day, the patient should apply only petroleum jelly to the affected area.
This approach will take 90% of patients out of the crisis stage. After a week or two, attention must shift to preventing recurrence, with generous use of emollients such as petroleum jelly. The patient should also be instructed to avoid using harsh (colored, scented, high pH) soaps, switch to shorter, relatively cool showers, and stop using anything but his hand to wash with (ie, no washcloths or loofahs).
For nondiabetic patients with severe AE that persists despite these measures, an intramuscular injection of a glucocorticoid (eg, triamcinolone 40 - 60 mg) can work wonders.
TAKE-HOME LEARNING POINTS
• Asteatotic eczema (AE), also called xerotic eczema or eczema craquele, is quite common, especially on the lower legs of older men.
• The particular rash of AE is said to resemble the cracked surface of a porcelain vessel.
• AE is often accompanied by edema distal to the rash.
• A topical steroid ointment applied to water-soaked skin, held in place overnight with an occlusive dressing, usually takes the patient out of the crisis phase.
• Prevention is then directed at avoiding drying of the affected areas.