lichenoid rash
Introduction
Introduction to frictional mossy rash Frictionallichnoideruptions (also known as juvenile paul dermatitis), recurrent summertimepityxiasisoftheelbowsandknees, sand dermatitis. The age of onset of papular dermatitis in children is often 2 to 9 years old. Boys are more common and occur in summer and autumn. Children often have a history of playing with sand or touching rough surfaces. The lesion is a polygonal or round papule with a needle-to-miliary size, a flat top or a dome, and a normal skin color, grayish white or reddish color. basic knowledge The proportion of illness: 0.005% Susceptible people: children aged 3 to 12 Mode of infection: non-infectious Complications: contact dermatitis
Cause
Rubbing mossy rash
Causes:
The cause is unknown and may be a non-specific skin reaction of children to external stimuli. The pathogenesis is not very clear; it is generally considered to be related to certain items or mechanical friction, such as playing sand, toys, etc. Because children are active and have poor self-control ability, they do not pay attention to contact methods and postures, causing exposed skin to rub with sand, toys, etc. Frequent exposure to substances causes disease, and some people think that it is caused by viral infection, but it has yet to be proved by experiments.
Prevention
Frictional moss-like rash prevention
Frictional moss-like rash, also known as juvenile papular dermatitis, is a chronic skin disease and a common skin disease in preschool children in spring, summer and autumn. In fact, this skin disease is a non-specific skin reaction to external stimuli. At present, the cause of the disease is still not very clear, but it has been found that there is often a history of contact or rubbing with certain items before the disease, such as more than playing with soil, soap foam or being stimulated by a blanket. Some experts believe that the disease may be related to viral infection, but it has not been confirmed so far. This disease is most likely to occur in children between the ages of 2 and 9, with more boys than girls, and more common with children who enjoy playing outdoors. Therefore, the best way to prevent this disease is to educate children to play less sand, reduce friction and control behavior.
Complication
Frictional moss-like rash Complications contact dermatitis bite dermatitis
Because the disease can directly cause the integrity of the skin to be destroyed, and the child is often accompanied by obvious skin itching, it can cause skin bacterial infection or fungal infection due to scratching, usually secondary to low body constitution, or long-term use of immunosuppressants And patients with fungal infections such as onychomycosis, such as concurrent bacterial infections may have fever, skin swelling, ulceration and purulent secretion and other performance. Severe cases can lead to sepsis, which should be brought to the attention of clinicians.
Symptom
Rubbing mossy rash symptoms Common symptoms Itching papules scaly edema
All are seen in children aged 3 to 12 years old, more common in boys, more than in spring and summer and early autumn. Children often have a history of playing sand or touching rough objects. Skin lesions are often symmetrically distributed, mostly limited to the back of the hand, the forearm is extended, sometimes Can be seen in the knuckles, elbows, knees and other exposed parts that are susceptible to irritating friction, occasionally extensively involving the wrist, foot and torso, the lesion is a miliary-sized flat or hemispherical papule, often densely integrated, but not fused, covered There are fine scaly scales, mild lichen-like changes, mild inflammation, generally normal skin color, heavier people may be light red, generally no symptoms, sometimes mild itching, the disease is self-limiting, but If it is easy to relapse after exposure to the original stimulus, the skin lesions remain dry throughout the course of the disease, no blistering, erosion and exudation.
Examine
Rubbing mossy rash
Clinical skin examination: more than spring and summer and early autumn, children often have a history of playing sand or touching rough items. Lesions are often symmetrically distributed, mostly confined to the back of the hand and the forearm. Sometimes they can be found on exposed parts such as knuckles, elbows, and knees that are susceptible to irritating friction. Occasionally, the wrist, foot, and torso are extensively involved.
Histopathology: changes for non-specific inflammation, including hyperkeratosis, acanthal hypertrophy, and mild lymphocytic infiltration of the dermis.
Diagnosis
Diagnosis and identification of frictional mossy rash
diagnosis
According to the clinical features of this disease, it is generally not difficult to diagnose.
Differential diagnosis
However, it is still necessary to distinguish it from the common insect bite dermatitis and caterpillar dermatitis in childhood. The two types of papules can be large, edema and inflammation are often obvious, and the pruritus is intense, sometimes with Giomotti-Crosti syndrome (children with papular acromegaly). It is not easy to distinguish, but the latter rash is more common, the papules are larger than the mung bean size, flatter, redder, and may have large liver and serum HBsAg positive, which is caused by natural infection of hepatitis B virus.
