The pustule is a localized epithelial cavity bulge containing turbid pus. It originated from the skin and evolved from papular blisters. Pustules vary in size, and there may be inflammatory redness around them. After the shallow pustules dry up, they become purulent and leave no scars. The pustules can form ulcers and leave scars.

Pustules refer to the cavity formed under the epidermis or epidermis, and the contents are herpes of pus. Most pustules are defensive inflammatory reactions caused by purulent bacterial infections, and some pustules are sterilized (related to toxic irritation, allergic reactions, etc.).

The hair follicle sebaceous glands are blocked and do not communicate with the outside world. First, whitehead acne is formed, and the surface is like a slightly protruding whitehead. When the whiteheads are worsened, papules will form, and the papules will become more inflamed and intensify, and pustules will form.



The mechanism of pustules varies with the cause. The cause of impetigo in some diseases remains unclear. However, a large number of white blood cells exist in the pustule cavity.

Viral acne-like pustules are infected by different viruses through droplets or contact infections, and after a series of immune reactions, epidermal or subepidermal pustules occur. Typical changes can cause reticular and balloon-like degeneration of the epidermis, as well as inclusion bodies of different viruses.

Bacterial infections are mostly caused by staphylococcal and streptococcal infections. The route of infection is primary infection and secondary infection. The primary infection is a pustule caused by the direct invasion of the pathogenic bacteria into the skin. Such as infectious impetigo, its pathogenesis pathogen plays a major role. Secondary infections occur on the basis of the original lesions. It is usually a mixed infection of various bacteria, such as infectious eczema-like dermatitis. The causative factor causing bacterial pustules, the pathogens multiply on the skin or contact with strains with strong external virulence, and the damage of the epidermis makes the pathogens easy to invade. Pediatric skin is thin and tender and resistant to infection. Metabolic disorders, malnutrition, fatigue or susceptibility to certain immune dysfunction.

Non-infectious rashes are aseptic pustules. The general cause is still unclear, such as herpes-like impetigo, pustular psoriasis. It is believed to be related to factors such as focal infection, endocrine disorders, and immune dysfunction.

(1) Infectious pus

1. Viral acne-like pus, Kaposi varicella-like rash, vaccination, vaccinia-like eczema, smallpox, sheeppox, vaccinia, milking man nodules.

2. Bacterial inflammatory pustular infectious impetigo, bullous impetigo, deep pustular sores, neonatal impetigo, follicular impetigo, necrotizing acne, blisters, alopecia folliculitis , hand (foot) superficial bullous pyoderma, pustular bacterial rash, infectious eczema-like dermatitis.

3. Fungal, spirochete, aphid infectious pustules are found in jaundice, purulent sputum, pustular syphilis, acne, hair follicle dermatitis.

(two) non-infectious pustules

This group of diseases aseptic small pustules, most of the causes are not very clear, such as pustular psoriasis, herpes-like abscess, subarachnoid pustulosis, palmoplantar pustulosis, continuous acrodermatitis, infants Limb impetigo, eosinophilic pustular folliculitis, pustular miliary rash, pustules caused by drugs such as bromine and iodine.


an examination

Related inspection

Alanine aminotransferase (ALT) Bacterial antibiotic resistance test Indirect fluorescent antibody uptake test (FLA-ABS test) against anti-epidemic basement membrane antibody leprosy

First, medical history

To understand the speed of the initial occurrence of pustules is the age of the primary or from the blister to the onset of pustular disease and to understand the cause of the disease is infected pustules or non-infectious pustules.

Acne-like pustules are found in viral infections. There is a history of epidemiological exposure to vaccination. There is a history of vaccination against vaccinia; vaccinia-like eczema is a acne-prone or acne-producing person who has a history of contact with sheep and cows.

Suspected pustules are an acute suppurative infection. Generally, there are inflammatory redness around the pustules on the basis of erythema. Only local symptoms are severe. There may be fever, chills, elevated white blood cells, etc. Systemic symptoms usually have local lymph nodes. The age of onset of the disease is also helpful in the diagnosis of infection such as infection, impetigo is more common in children with neonatal impetigo found in neonatal necrotizing acne. Sore is easy to occur in 30-50 years old male alopecia folliculitis is more common in young adults with some abscesses Occurs in certain parts such as jaundice and purulent sputum in the scalp hair. To understand the history of personal infection, such as hemorrhoids, infection, exposure to sesame-induced abscesses, history of sputum and history of syphilis.

Second, physical examination

(a) the nature of the pus treatment

Abdominal superficial relaxation of the abscess is thinner under the horn layer and intraepithelial abscess is seen in the generalized pus-type psoriasis submucosal pus tumor acne-like pus cancer infectious pus cancer neonatal sepsis The top of the purulent sputum has a umbilical fossa for viral infection. The abscess at the bottom of the abscess is seen in the large cancerous impetigo sore. There is often a swollen lymph node around the inflammatory redness.

(2) The location and number of pus treatments

Pustoma occurs in the palm of the hand and is seen in the palmar purulent sputum purulent rash and palmar abscess-type psoriasis continuous acromegaly. The abscess occurs in the head of the pus at the end of the finger. Purulent sputum alopecia folliculitis necrotizing acne pus cancer occurs in the face and the center of the chest and back.

(3) Arrangement of pus treatment

It is very meaningful for diagnosis. The abscesses are arranged in a ring or arc shape. They are found in the psoriasis. The sore-like pus cancer is formed into a paste and is found in the generalized abscess-type psoriasis pityria-like impetigo.

Third, laboratory inspection

Viral infection of abscess peripheral blood granulocytes is low or normal, such as combined infection of granulocytes can be slightly increased, pathogenic microbial DNA gene detection can help to diagnose histopathology with characteristic visible reticular degeneration and balloon-like degeneration at the bottom of balloon cells Bacterial abscess containing viral inclusion bodies with granulocyte-enhanced pus culture has pathogenic bacteria growth. Due to the different strains of the infected strain and the different depths of the lesions, the histopathological manifestations are: inflammatory reaction such as oocyst infiltration of abscess and necrosis, and the direct microscopic examination of the fungal infection of the abscess fungus. Positive reaction. The culture of non-infectious pus tumors is generally negative, and blood routines can be checked according to different conditions. The pathology of rabbit plaque globulin is helpful for diagnosis.


Differential diagnosis

The diagnosis should be differentiated from the following symptoms:

1. Small pustules on the skin folds during pregnancy

Herpes-like impetigo manifestations are small pustules at the skin folds during pregnancy. Herpesigo herpetiformis (impetigo herpetiformis) is a serious skin disease that occurs in pregnant women. The basic damage of the skin is the appearance of aseptic pustules on the basis of erythema, often accompanied by severe systemic symptoms. Gradually relieve after childbirth, re-pregnancy can relapse.

2. Pustular acne pustular acne

Puss is the main expression, pustules are the size of grain to mung bean, pustules are formed at the tip of follicular pustules and papules, and the pus is thicker after the break, leaving a shallow scar.

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