Pigmented urticaria

Introduction

Introduction to pigmented urticaria Urticapigmentosa is a mast cell disease with round or oval pigmentation spots or pigmented nodules. It becomes red and bloated after rubbing, often starting in early childhood. Nettieship first described this in 1969. The skin manifestations of the disease, called chronic urticaria with brown spots, Unna pointed out the relationship between the disease and mast cells, Ellis first reported that the disease except the skin, other organs such as liver, spleen, bone marrow, lymph nodes, etc. Both can be infiltrated with mast cells. Usually a benign process, the rash in children can resolve on their own. basic knowledge The proportion of illness: 0.001% Susceptible people: no special people Mode of infection: non-infectious Complications: urticaria

Cause

Cause of pigmented urticaria

Congenital factors (30%):

Excessive concentration of mast cells in the skin can be related to congenital, vaccination, injection of tetanus anti-drug, occurrence of chickenpox or measles, and even mental stimulation, can promote this congenital abnormal disease.

Genetic factors (30%):

Pigmentation of the skin is due to melanin hyperplasia, and plaques and nodules are caused by a large accumulation of mast cells. The Lewis triple reaction shows that the site of frictional lesions can cause mast cells to release histamine and other substances, thereby affecting capillaries. The diastolic and permeability of the wall, so there is a local wheal rash.

Because this disease is more common in some races, it can be seen that the family is affected, and one of the parents and one or two children are suffering from this disease, so it is considered to be recessive.

Prevention

Pigmented urticaria prevention

The disease generally has no symptoms, but under the influence of trauma, scratching, temperature changes, or the intake of certain foods or drugs, erythema and itching may occur, and a few may have skin flushing, nausea, vomiting, Systemic symptoms such as abdominal pain and tachycardia. Therefore, it is necessary to avoid irritating factors, disable aspirin, morphine and other drugs to promote histamine release, avoid eating sea fish, salted products, etc. to promote histamine release food, wear soft cotton clothing to avoid mechanical stimulation; avoid overheating, strenuous exercise, emotions excitement. Patients with severe symptoms may consider medication.

Avoid foods with high levels of histamine or promote histamine release, such as seafood, shellfish, mushrooms, pickles, alcohol, spicy foods or not fresh foods. Avoid drugs that promote histamine release, such as morphine, aspirin, codeine, quinine, hydralazine, pilocarpine, papaverine, polymyxin B, and the like.

Complication

Pigmented urticaria complications Complications urticaria

In adult rashes rarely disappear, a small number of patients with systematic invasion, can be a chronic progressive disease, and a very small number of cases to malignant, but most of them are benign.

Symptom

Pigmented urticaria symptoms Common symptoms Cheeks and upper chest congestion, hemorrhagic pigmentation, itching, splenomegaly, papules, wind, papules, swollen lymph nodes, spotted nodules

Common in children, more than 3 to 9 months after birth, but there are also birth, there is no effect on the growth and development of the child, but children have hepatosplenomegaly, ascites and other visceral damage, the initial damage often It is a temporary rash, which often recurs and disappears in the future. It finally becomes a persistent melasma or a pigmented nodule with uneven surface. A small number of patients may also have blisters on the skin lesions. This is the characteristics of this disease, damage often appears in batches, the size is uncertain, generally peas to broad beans, the number is not fixed, only a few, more can be scattered throughout the body, and some slightly itchy, swollen lymph nodes A few people's rashes appear in adulthood and can persist for a long time, so some scholars divide them into the following types:

Benign:

(1) Skin type diffuse skin mast cell hyperplasia.

(2) Systemic skin, bone, liver, spleen, gastrointestinal damage.

(3) Visceral spleen, bone and gastrointestinal damage.

2. Malignant: leukemia.

Examine

Examination of pigmented urticaria

Common in children, more than 3 to 9 months after birth, but there are also birth, there is no effect on the growth and development of the child, but children have hepatosplenomegaly, ascites and other visceral damage, the initial damage often It is a temporary rash, which often recurs and disappears in the future. It finally becomes a persistent melasma or a pigmented nodule with uneven surface. A small number of patients may also have blisters on the skin lesions. This is the characteristics of this disease, the disease is no special.

Diagnosis

Diagnosis and identification of pigmented urticaria

diagnosis

Typical cases are not difficult to diagnose, and the formation of wheal formation of pigmented skin lesions (Parier sign) has diagnostic value.

All types of characteristic mast cell aggregation groups occur between the collagen fibers in the superficial dermis, but also in the blood vessels, around the hair follicles and sweat glands, and in the interstitial space. The granules of mast cells are composed of mucopolysaccharides with Giemsa and Toluidine blue is metachromatic, and if the particles are lost, the mast cells are not easily identifiable.

In the lesions of pigmented spots, there is sparse mast cell infiltration in the upper part of the dermis, mainly distributed around the blood vessels. The mast cells are spindle-shaped nucleus, similar to fibroblasts, accompanied by nucleated eosinophilic cytoplasm, showing a small number of eosinophils. In the upper epidermis, the melanin is increased, and in the lesions damaged by the nodules, there is a large amount of dense tumor-like mast cell infiltration in the whole dermis, which is common to obvious particles.

Mast cells showed a banded infiltration in diffuse lesions, and infiltration of mast cells was observed in systemic tissues in systemic lesions.

Differential diagnosis

Pigmented rash should be differentiated from sputum, papules, nodular lesions should be differentiated from juvenile yellow granuloma and xanthomas. In addition, it should be differentiated from drug eruption, coloration after inflammation, melanosis, and local irritation caused by this disease. It can cause wheal reaction, and the infiltration of mast cells can be confirmed in histopathology.

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