Contact dermatitis is certainly one of the more common skin problems dermatologists encounter. The cause may be something the patient is allergic to or something that is a primary irritant.
Poison ivy is a common culprit. Findings on the skin characteristically are linear vesicular (blistering) streaks of a very pruritic (itchy) dermatitis anywhere on the body where exposed to the plant or its juice. Once started, it can crescendo rapidly covering extensive surface areas with considerable to the quality of life. The sooner therapy is instituted, the quicker the response. The problem is recurrent with re-exposure to the plant. Effective desensitization is not available at this time.
With other contact dermatitis, look for uncommon geometric shapes such as straight lines, right angles, tear drops and other lesion configurations seen as unnaturally occurring conditions. When your suspicion is arisen, take a good history.