I have a number of patients suffering from eczema, and came across this handy list in Acupuncture Today of the possible triggers. In Chinese Medicine, eczema can present with many different patterns and one treats accordingly.
dust mite allergies
infections (staph, strep, or herpes simplexa0
Dry, cold weather (decreased humidity)
wool clothing or blankets
emotional stress (a trigger, not a cause)
Info on my practice here.