1. Contact with impetigo contagiosa/impetigo vulgaris

2. Deep impetigo (ecthyma)/ecthyma: Mainly caused by hemolytic streptococci, more common in malnourished children/elderly people, and more likely to occur on the calves/buttocks; it starts as pustules and gradually develops into the deeper parts of the skin, with pustules on the surface. Necrosis and oyster shell-like black thick scab, with obvious redness and swelling around it. After removing the thick scab, a saucer-shaped ulcer with a steep edge can be seen; the pain is obvious

3. Bullous impetigo (impetigo bullosa): Mainly caused by Staphylococcus aureus infection of bacteriophage group Ⅱ type 71; manifested as scattered bullae (diameter 1~10cm), there may be pus accumulation in the blister, and large tracts will be formed after rupture Erosive surface; the skin lesions can heal themselves in the middle and expand to the periphery like a ring (impetigo annularis), and multiple rings can merge into a gyrus (impetigo gyrus)

4. Neonatal impetigo: It is a special type of bullous impetigo. It usually occurs 4 to 10 days after birth and is highly contagious. It manifests as multiple large pustules widely distributed and positive Nissl sign. There is a blush around the blister, and a red eroded surface will form after rupture; the condition progresses quickly and soon spreads to the whole body, causing high fever, lethargy, vomiting, diarrhea, green stool, and even bacteremia, pneumonia, and meningitis, and the prognosis is poor

5. Staphylococcal scalded skin syndrome (SSSS): caused by epidermal exfoliation toxin produced by coagulase-positive, phage group II type 71 Staphylococcus aureus. It is more common in children under 5 years old; onset Most of the time, there is an upper body sensation or purulent infection of the skin all over the body; the characteristic manifestations are flaccid blisters on the basis of large erythema, positive Nissl sign, and large areas of skin peeling off, leaving a flushed and eroded surface, like a burn, with obvious folds. ; The skin of the hands and feet can be peeled off like gloves or socks, and radial cracks can be seen around the mouth, but there is no damage to the oral mucosa; the skin lesions have obvious pain and tenderness; mild cases can be cured after 1 to 2 weeks, and severe cases can be due to complications (such as sepsis) , pneumonia) and endanger life

Skin lesions: various manifestations (such as macules, papules, nodules), leprosy bacillus can often be found (especially tumor type and borderline leprosy); skin appendages can be affected (hair loss, sweating disorder)

Peripheral nerve damage: When there is only peripheral nerve damage without skin damage, it is called "pure neuritis leprosy"

lepra reaction

leprorisin test

Clinical classification

medical treatement

leprosy reaction

complication

[Cause] Mostly caused by coagulase-positive Staphylococcus aureus infection

[Clinical manifestations]

[Cause] Beta-hemolytic Streptococcus causes acute inflammation of lymphatic vessels in the skin and subcutaneous tissue and surrounding soft tissues

[Clinical manifestations]

【Differential Diagnosis】

[Treatment] Bed rest in the acute stage; penicillin is the first choice, used for at least 10 days, and continued for a few days after the skin lesions subside.

[Cause] Mainly hemolytic Streptococcus and Staphylococcus aureus

[Clinical manifestations] It initially appears as diffuse, edematous, and infiltrative erythema with unclear boundaries, increased local skin temperature, and obvious redness and swelling in the center of the skin lesion. In severe cases, deep suppuration and tissue necrosis may form; in the acute phase, there are often symptoms of pain and systemic poisoning. , the skin shows hardening and atrophy in the chronic stage (similar to scleroderma)

[Treatment] Mainly systemic drug treatment

1. Caused by exogenous vaccination: such as tuberculous sores and verrucous skin tuberculosis

2. Caused by endogenous diffusion/self-inoculation: such as scrofula, cutaneous tuberculosis, and oral tuberculous ulcers

3. Hematogenous spread to the skin: such as lupus vulgaris, acute miliary cutaneous tuberculosis, tuberculous ulcer, gumma, and abscess

4. Tuberculosis rash: such as hard erythema, papule necrotizing tuberculosis rash, scrofula, lichenoid skin tuberculosis; Mycobacterium tuberculosis is not easily found in the damage (it has been cleared by the body's immunity)

1. Lupus vulgaris (50~70%): ① Caused by re-infection of Mycobacterium tuberculosis in those with positive tuberculin reaction; more common in children and young people; more likely to occur on the face; ② Mainly manifested as brown-red nodules with texture It is soft, has penetration phenomenon on probing, and looks like applesauce when pressed on the glass (Apple jelly phenomenon); the damage can expand to the surroundings, fuse, and have obvious edges; ③ can be absorbed/ulcered by itself, leaving atrophic lesions after healing Scar, new nodules may appear on it (old and new skin lesions coexist); ④ It may be accompanied by tuberculosis in other parts, and the tuberculin test is positive

2. Scrofula cutaneous tuberculosis (10~15%): ① often caused by the spread of bone/lymph node tuberculosis; more common in children; prone to occur in the neck; ② initially subcutaneous nodules, hard and movable ; Then it enlarges and adheres to the skin, turns red, gradually softens, ruptures, and forms a fistula, and cheese-like material/thin pus may be discharged; ③The edge of the ulcer may be latent, leaving a typical cord-like/indistinct appearance after healing Regular/uneven scars; ④ The above lesions are often visible at the same time, and the tuberculin test is positive

3. Tuberculosis verrucosa cutis (4~5%): ① Caused by exogenous inoculation of Mycobacterium tuberculosis into immunocompetent individuals; more common in male adults; most common on fingers; ② Initially a single purple soybean-sized tuberculosis Small red papules with hard texture, and then the surface becomes keratinized to form warty nodules and hard texture, and then proliferates into sheets; ③ The periphery of the fully developed lesions is inflammatory redness; there are papilloma-like protrusions inside, covered with sticky scabs or accompanied by cavities The gap forms an ulcer, and pus overflows when pressed; the center can be healed, leaving a smooth, soft and superficial reticular scar; the above are collectively referred to as the "triple contour sign"; ④ The tuberculin test is strongly positive