He Tried So Hard to Avoid It …
DISCUSSION
It has been said that humor is tragedy plus time; certain skin diseases, such as shingles or poison ivy, certainly provide fodder. In the midst of an attack, however, these conditions can produce not only miserable symptoms of itching, pain, and sleeplessness, but also considerable mental anguish regarding contagion.
Repeated polls of the general public reveal an almost universal belief that poison ivy is contagious and that scratching spreads it around the body. Research, and a thorough knowledge of the pathophysiology involved, have long since disproven both concepts. So while the inclination to distance oneself from an affected person is understandable, there is actually no need to do so. For the patient, facing six weeks or more of isolation is no laughing matter (at least, until long after the fact).
This particular case highlights one other pertinent issue with poison ivy: As the photos established, the patient had carefully avoided the wrong plant. The five dart-shaped serrated leaves suggest Virginia creeper—certainly not poison ivy. This may sound like a minor issue, but it is quite possible that while the patient was steering clear of a harmless plant, he was in fact coming in contact with the one he should have been concerned about.
True poison ivy, Toxicodendron radicans, can develop as a bush, a vine that stays low to the ground, a small tree, or even a climbing vine that can reach 30 feet or higher into mature trees, especially along waterways or in low, boggy land. The vines can attain a thickness of more than 3 in and have a surface covered by tiny “rootlets,” giving them a shaggy look.
Regardless of the plant’s form, its leaves are always found in threes, protruding from the same stem. The leaves are diamond shaped, can reach a length of 10 in, and often have a single notch on the margin that is said to resemble the outline of a thumb. The plant produces white berries in late summer or early fall.
It has been estimated that the number of poison ivy plants has doubled since 1960, for at least two reasons. First, an increase in population has led to more land being cleared for housing; many properties now border woodlands, which are an ideal environment for this plant.
Second, and more surprising, poison ivy thrives in a CO2-rich environment. Carbon dioxide in the atmosphere has increased significantly in the past 50 years and will continue to do so. Experts predict that the density of poison ivy will double again in the next 20 years as a result. The potency of the urushiol, the offending substance in the stems and leaves, is expected to increase as well.
The patient (height, 6’3” and weight, > 300 lb) was treated with a 60-mg IM injection of triamcinolone, a two-week, 40-mg taper of prednisone, and twice-daily application of betamethasone cream. This, of course, followed a discussion of the risks versus benefits of such a course of action.
TAKE-HOME LEARNING POINTS
• Climbing vines with five serrated leaves coming off the same stem are probably Virginia creeper and not poison ivy.
• Poison ivy is not contagious, cannot be spread by scratching, and is not poisonous in any way.
• The rash produced by poison ivy exposure can be severe and can last six weeks or more without treatment.
• The number of poison ivy plants has doubled in the past 50 years and is expected to double again within 20 years. The potency of the plant’s allergen is also expected to increase.
