Erythema is redness of the skin. It is caused by problems with the capillaries in the affected area. It can be associated with a wide range of medical issues, including chronic and acute conditions, trauma, inflammation, infection, and some genetic conditions. Commonly it is a symptom of an underlying medical issue and it can be an easily spotted warning sign because most people notice the change in skin color.
Many cases of erythema take the form of erythema multiforme, which is caused by allergies and some types of viral infections. Another example is erythema nodosum, in which fat cells under the skin become inflamed and red nodules develop. Erythema toxicum is a version seen in some newborn babies, characterized by a distinctive rash which resolves on its own in most cases. Radiation exposure, exposure to the sun, and exposure to infrared radiation can all cause erythema as well.
When a patient presents with erythema, the first step is to determine what is causing the redness. If the patient is experiencing immediate discomfort, medications may be provided to address symptoms like itching and soreness. Diagnostic procedures can include blood work, a physical examination, an interview with the patient, and a review of the patient's history. Once the cause is determined, the doctor can start to provide treatments for the cause, which should resolve the reddened skin as well.
For example, if a patient has erythema because of a viral infection, antiviral drugs can be provided to treat the infection. Conversely, if inflammation is the cause, steroids may be applied to mitigate the immune response which is causing the inflammation. There may be cases in which erythema is recurrent, a common problem with allergies and some autoimmune disorders, in which case the skin may become permanently discolored as a result of damage to the underlying capillaries.
Red skin in and of itself is not necessarily harmful, but it can be a sign of a serious underlying medical problem. If someone notices a rapid change in skin color, it is advisable to discuss with it with a doctor. The doctor can evaluate the situation to determine whether or not additional action should be taken. It is especially important to be alert to changes in skin color or texture for people who work in environments where high levels of radiation are present. This includes people exposed to infrared radiation, such as the heat from a laptop, which can cause erythema if the laptop is routinely used on someone's lap.