Spring is shining!
After the epidemic ushered in a sunny day.
However, there are also significantly more patients with "red faces" and itchy hands and necks in the outpatient clinic.
In addition to airborne allergies such as seasonal pollen, various types of photodermatosis are also important players.
Xitang in life
There are dozens of common photodermatosis, such as simple and rough solar dermatitis (sun spots), chronic photosynthetic dermatitis (CAD) common in elderly men, photoprurigo that likes to bully children, or adolescent spring rash...
Edematous erythema, papules, scales, pigments
Today we will talk about one of the very classic, "lustful" -
<h1 class="pgc-h-arrow-right" > polymorphic solar rash</h1>
As early as 1900, Rasch named this photosensitive skin disease associated with daylight exposure.
Why do you say "lustful"?
In addition to its red lesions, it is more important to occur in young women, especially those with whiter skin.
Papule type, densely distributed small papules
<h1 class="pgc-h-arrow-right" > disease as its name suggests</h1>
Since it is called "sun rash", it often occurs 2 hours to a few days after sun exposure, and is manifested by lesions in the lower V area of the neck (neckline), the extensor side of the back of the hand and upper limbs, the face, the back of the neck, the calf, etc., but often focus on a certain part rather than all exposed parts.
Other photodermatos are, of course, mainly based on these sun-prone areas (some of which can also occur in other places for a long time), characterized by the "polymorphism" of the rash.
Such as edematous erythema, maculopapular rash, papules, blisters, plaques, licheniform changes and so on.
Unlike eczema, although the lesions can vary greatly from patient to patient, the same patient tends to have one type of lesion. Therefore, clinically, according to the main lesion characteristics, it is divided into papules type, papule type, pruritus type, erythematous erythematous type, polyform erythematous type and mixed type.
There is a pronounced seasonality (spring, early summer), recurrent, conscious itching and burning sensation.
Blisters, papules, scabs
<h1 class="pgc-h-arrow-right" > culprit</h1>
The culprits of polymorphic solar eruptions are mainly UVA (long-wave ultraviolet rays), and a few are caused by UVB (medium-wave ultraviolet) and visible light.
Some people have a family history of photosensitivity.
In women, pregnancy may affect the course of the disease, suggesting the presence of endocrine factors.
Immunological changes (such as late-onset hypersensitivity reactions) and photooxidation reactions are also one of the pathogenesis.
Eczema type, also known as papule type
<h1 class= "pgc-h-arrow-right" > see flowers in the fog</h1>
Of the more than 2,000 skin diseases, many of which present as itchy erythema, papules, blisters, erosions, exudation, scabs, desquamation, and if also confined to these exposed areas, how can they be distinguished from polymorphic solar rashes?
The first is, of course, a complete medical history.
These include age of onset, sex, occupation, time between rash and sun exposure, duration of rash, conscious symptoms, drugs, foods, cosmetics, and suspicious chemical exposures, previous reactions to light, and family history.
If you just throw a photo online, the probability of "guessing" is definitely low.
The above accurate information is provided, some of which can support the judgment of polymorphic solar rash, and some of which can exclude other diseases similar to it, and finally form a complete "chain of evidence" to provide key details for a correct diagnosis.
The second is the characteristics of skin lesions
For example, distribution, although some airborne contact dermatitis is also more likely to occur in exposed areas, such as pollen, air fresheners, etc., but often the lesions are more diffuse, the contact site occurs in pieces, and the polymorphic solar rash is dominated by prominent parts, and there is often normal skin between the rashes, which is also the neck, the neck side, the back of the neck, the V-shaped area, and the front of the neck is not easy to occur, because the chin blocks the light. If it is contact dermatitis caused by cosmetics, it is consistent with the contact site of cosmetics, and the lesion form is single (often manifested as erythematous edema), which is not related to sun exposure.
The type of lesion in each patient with polymorphic solar eruption is often fixed, and different sites can have different lesions.
Finally, some checks can be combined
For example, in ultraviolet tests, the erythema reaction is often stronger than normal people, and the peak appears late and lasts longer.
Others include photostimulation tests and patch tests, the latter of which help in the diagnosis of phototact dermatitis.
Other photodermatos also have their own characteristics, here are examples!
<h1 class = "pgc-h-arrow-right" > solar dermatitis</h1>
The realm is clear, and the form is single sunburn
Also known as sunburn or sunburn.
It is an acute phototoxic reaction caused by UVB, and has nothing to do with allergies (allergic reactions), and should not be confused with "photosensitive dermatitis".
As long as it is exposed to a certain level, it can happen to anyone. In theory, women and children's skin is more delicate, in practice, it is not uncommon for men to be young and mature in clinical practice, in order to reflect the style of Hanzi, often pay less attention to sun protection, and like to show naked and unprotected for a long time on the beach.
Clinical manifestations are often similar to those of a first-degree burn, after intense sun exposure (plateau, snow, water surface), diffuse edematous bright red spots with clear boundaries at the exposed area, with a burning sensation or tingling, tenderness, darkening over time, desquamation, pigmentation. Particularly severe cases can produce systemic symptoms such as chills, fever, headache, and nausea.
<h1 class= "pgc-h-arrow-right" > chronic actinic dermatitis (CAD</h1>).
Although the lesions are extensive, the skin at the sunken area is relatively normal
Elderly men predominate.
Early manifestations are photosensitive dermatitis (PD) with eczema-like appearance at the site of exposure, and late stages, called rayoid reticuloblastic hyperplasia (AR), are infiltrated with a hypertrophic lion's face and pathologically pseudo-lymphoma-like.
The rash occurs after a few days of sun exposure, which lasts for a long time, unlike the multiform solar rash, which changes quickly and seasonally.
Others such as actinic eruptions should have a history of taking photosensitivizing drugs, such as hydrochlorothiazide (diuretics, antihypertensives), and quinolone antibacterials. Plant-solar dermatitis first eat amaranth, mustard greens, lettuce, maran head, gray cabbage, astragalus and other photosensitive plants, and then occur after the sun, the experience of swelling like a pig's head will be unforgettable.
Actinic drug eruptions caused by Chrysanthemum antihypertensive tablets
It's too long, stop!
Finally, let's talk
<h1 class = "pgc-h-arrow-right" > the prevention and treatment of polymorphic solar rash</h1>
During the onset of the disease, do a good job of sun protection, such as umbrellas, wide-brimmed hats, long sleeves and other hard sunscreen, reduce going out on sunny days, and use sunscreen correctly.
Usually, through outdoor exercise, gradually improve the tolerance to light exposure, but do not be too violent at once.
Polymorphic solar rashes have a very interesting "sclerosis phenomenon": that is, the sun is continuously exposed for a season, and finally the skin no longer reacts to ultraviolet rays. Just like some children who are originally allergic to eggs and milk, they slowly tolerate desensitization at a certain age, and many times it is not necessarily a good thing to be too delicate.
Clinically, it can be effectively treated by photochemotherapy such as PUVA, or narrow-wave UVB, when the skin gradually darkens and the stratum corneum thickens, the multiform solar rash will disappear. Of course, it can't be too fierce at once, it needs to be gradual.
If you are intolerant to PUVA, you can choose chloroquine or hydroxychloroquine, is it familiar? It is the net red drug used to treat the new crown virus infection during this time, and the latter has less side effects.
It has been mentioned before that the internet celebrity in skin care products, niacinamide, can also reduce photosensitivity, is oral rather than topical, and requires a larger dose.
Another old drug with a story, reaction stop (Shadulian), although in the last century stabbed a large basket, causing "seal-like baby" deformity, but as long as the indications are selected, it has a good effect on many stubborn skin diseases and rheumatism, such as some photosensitive skin diseases. Recently, there have also been reports of use in the treatment of new crown pneumonia.
The efficacy of carotene is also controversial.
For particularly severe, killer tools such as glucocorticoids and immunosuppressants (azathioprine)
Forearm extension (radial side)
Fortunately, although the polymorphic solar rash is easy to repeat, it can often recede after avoiding the sun, and it can disappear naturally after a few years, or how to say that it is good to have white skin and beautiful young women!
Those that have not regressed belong to the category of persistent light reactions, or are classified as chronic actinic dermatitis.
in a word
Do a good job of daily skin care, maintain a healthy life,
The final victory must belong to us!