Patches of bumps on your skin are usually caused by something benign and treatable. If you're concerned, see your doctor, who can diagnose your condition or refer you to someone who can.
Causes of Bumps
Red bumps develop on your skin when your body has encountered something it considers foreign. As Kim Barrett and colleagues detail in "Ganong's Review of Medical Physiology," both the redness and the bumps result from your skin releasing molecules that promote leakiness of veins and capillaries in the region of the irritant. Several elements can cause red bumps to develop on your skin. Two common causes are related to allergies and infections.
About Contact Dermatitis
Contact dermatitis occurs when you come into contact with something you are allergic to. Examples include poison ivy, poison oak and latex. According to Timothy Berger in "Current Meidcal Diagnosis and Treatment," contact dermatitis appears as red, itchy, bumpy skin, sometimes with clear fluid leaking from the bumps. These findings occur in the pattern of the thing you touched that you were allergic to. For example, if you were allergic to a latex glove, they will appear in a glove distribution. Topical steroid creams are usually the first-line treatment for this condition, which usually clears up in a week or so.
Infection
A classic infectious cause of patches of bumps on the skin is viral infection, either with varicella zoster, the virus that causes chicken pox, or herpes zoster, the virus that causes cold sores. The herpes virus manifests as a group of bumps filled with clear fluid that are clustered on a patch of red, inflamed skin, says Lawrence Corey in "Harrison's Principles of Internal Medicine." Herpes lesions tend to recur in the same place, so if you've had one outbreak, and you develop the same symptoms in the same location at a later time, it's likely that you're having another outbreak. Several antiviral medications can be prescribed to treat herpes.
Worrisome Signs
According to "Current Medical Diagnosis," if you developed bumps in association with shortness of breath or swelling of your tongue and throat, you might be having a more serious kind of allergic reaction called anaphylaxis. Seek medical attention immediately. Alternatively, if your red bumps develop yellow crusts, begin to spread, or start to sprout red lines leading away from them, under your skin, you may have cellulitis, a kind of bacterial infection that requires an antibiotic to treat.
Treatment and Prognosis
While treatment and prognosis ultimately depend on the cause of the bumps on your skin, for all the causes listed in this article, the treatment is relatively straightforward -- for example, steroids for contact dermatitis and antivirals for herpes -- and the prognosis is quite good, provided you are treated adequately and early enough in the course of these conditions. Herpes infection tends to produce recurrent outbreaks, and if you are infected with herpes, you may be infectious even if you are not actively experiencing an outbreak. Therefore, although herpes is manageable, it is not a curable disease.
References
- "Harrison's Principles of Internal Medicine"; Anthony S. Fauci, Eugene Braunwald, Dennis L. Kasper, Stephen L. Hauser, Dan L. Longo, J. Larry Jameson, and Joseph Loscalzo (editors); 2008
- "Current Medical Diagnosis and Treatment"; Stephen J. McPhee and Maxine A. Papadakis (editors); 2009
- "Ganong's Review of Medical Physiology"; Kim E. Barrett, Susan M. Barman, Scott Boitano; 2010
