Smith-Johnson syndrome

Introduction to history-syndrome In 1922, Stevens and Johnson first described the history-synergy syndrome, "Stevens-Johnson syndrome." The syndrome is an acute blister lesion involving the skin and mucous membranes. basic knowledge The proportion of illness: 0.001% Susceptible people: no special people Mode of infection: non-infectious Complications: anterior uveitis

History of the syndrome

(1) Causes of the disease

The occurrence of Stevens-Johnson syndrome is associated with a variety of factors, such as systemic medication, topical medication, infection, malignancy and collagen vascular disease.

(two) pathogenesis

In Stevens-Johnson syndrome, the triggering factor for the immune response is unclear. Although the drug plays an important role in the development of Stevens-Johnson syndrome, its clinical features and experimental studies do not support it as a rapid hair style. Hypersensitivity, the role of infectious factors in its pathogenesis has not been determined.

In the acute phase of Stevens-Johnson syndrome, a large number of deletions of OKT4 cells may occur. The main infiltrating cells of toxic epidermal necrolysis-soluble Stevens-Johnson syndrome skin are OKT4 subpopulations, and Langerhans cells may also function as antigen-presenting cells. Or the production of certain lymphokines, which chemotactic T helper cells enter these sites, the number of CD8 lymphocytes in the blister fluid of patients with toxic epidermal necrolysis and Stevens-Johnson syndrome is significantly increased. These lymphocytes lack CD45RA. Has a high level of CD29, which indicates that they are sensitizing cytotoxic T cells, may be important regulatory cells and effector cells, IFN-1b may have the role of promoting erythema multiforme formation, IFN- produced against antigenic stimulation It promotes the expression of cell adhesion molecules that bind killer T cells to epidermal cells.

The positive rate of HLA-B12 in patients with toxic epidermal necrolysis and Stevens-Johnson syndrome was significantly increased. The incidence of HIA-B12, HLA-DR7 and HLA-A29 was significantly increased in patients with sulfa drug-associated toxic epidermal necrosis. It is still difficult to determine whether toxic epidermal necrolysis is related to genetic factors.

History-syndromic syndrome prevention

There are no effective preventive measures for the disease, and early detection and early diagnosis is the key to the prevention and treatment of this disease.

History-syndromic syndrome complications Complications, anterior uveitis, globule adhesion

Can be complicated by severe anterior uveitis, corneal ulcer, valgus varus, sputum adhesion, corneal vascularization and tear film instability.

History-Symptom Syndrome Symptoms Common symptoms Toxic corneal ulcer uveitis varus gastrointestinal bleeding skin affected sore throat papule cyst photophobia

The clinical manifestations of pleomorphic erythema-type Stevens-Johnson syndrome are diverse, but one patient has only one manifestation. The diameter of the local lesion is often <3 cm, and the affected skin area is no more than 20%. The lesion has a sudden onset. It often appears on the dorsal and forearm of the hands and feet, the legs, the soles of the feet, and the surface of the soles of the feet. Its early manifestations are ring-shaped erythema and papules, and can cause damage to target organs. Some lesions can fuse into vesicles or blisters. There is urticaria, the duration of this lesion usually does not exceed 4 weeks, systemic symptoms include fever, sore throat, discomfort, joint pain and vomiting, vesicular lesions may involve the oropharynx mucosa, conjunctiva, genital mucosa, lips The visceral, pleomorphic erythema-type Stevens-Johnson syndrome lesions involve less than 20% of the skin area.

The prodromal symptoms of toxic epidermal necrolysis-soluble Stevens-Johnson syndrome include discomfort, fever, burning sensation of the conjunctiva and skin. The rash is often measles-like, and can affect the face and extremities. The lesions can fuse with each other in the later stage, resulting in a large The formation of blister and skin exfoliation, the toxic epidermal necrolysis is characterized by more than 20% of the damaged area of the skin, oral mucosa, lip mucosa, genital mucosa and conjunctiva can also be affected, but also fever, leukocytosis, renal failure, lung Embolism, gastrointestinal bleeding, sepsis and other phenomena.

1. Early eye performance

Non-specific conjunctivitis can occur in Stevens-Johnson syndrome, but conjunctivitis often occurs before skin involvement, and 15% to 75% of patients with Stevens-Johnson syndrome develop bilateral catarrh, suppurative and pseudomembranous Conjunctivitis, in addition to severe anterior uveitis, corneal ulcers can occur in the acute phase of the syndrome, the duration of which is generally 2 to 4 weeks, Stevens-Johnson syndrome only involving single eyes is rare.

2. Chronic eye disease

Due to the presence of inflammatory reaction, conjunctival scar formation often occurs in the chronic phase. When adhesions occur in the conjunctiva and sacral conjunctiva, eyelid cysts may occur, and tearing of the lacrimal passage caused by destruction of the conjunctival goblet cells may cause tear film abnormality if the patient Without tear scarring, there may be photophobia. The abnormal tear film in these patients is caused by the lack of mucous layer and corneal dryness. The varus and trichiasis can cause corneal epithelial defects, and corneal lesions are not the initial manifestations of acute inflammation. It is caused by goblet cell dysfunction, trichiasis and dry eye syndrome.

3. Secondary eye performance

A small number of patients with Stevens-Johnson syndrome may have secondary conjunctival inflammation that is unrelated to trichiasis, valgus, keratoconjunctivitis, and blepharitis. This conjunctivitis lasts for 8 to 5 weeks.

History-test syndrome

1. Feasible HLA-B12, HLA-DR7, HLA-A29 related laboratory tests to differentiate from toxic epidermal necrolysis and Stevens-Johnson syndrome.

2. Histopathological changes in the eye: Patients with erythema multiforme erythema-type Stevens-Johnson syndrome may have non-specific inflammatory reactions in the acute phase, and extensive arterioles and venous necrosis may occur, accompanied by collagen fibers. In the chronic phase of the disease, the scarring of the cornea, conjunctiva and eyelids is more obvious. The conjunctival biopsy of Stevens-Johnson syndrome has the phenomenon of goblet cell loss. In the acute phase of Stevens-Johnson syndrome, it is non-special. Heterologous inflammatory cell infiltration is characterized by the involvement of the epithelial layer of the conjunctiva. Circulating immune complexes are found in the microvessels under the epithelium. In Stevens-Johnson syndrome, there is a proliferation of basal epithelial cells and the extent of conjunctival cell proliferation. It has a certain relationship with the severity of the disease.

3. Pathological changes of the skin: pleomorphic erythema can occur between the epidermis and the basement membrane, endothelial edema, perivascular infiltration of lymphocyte-tissue cells, and drug-related Stevens-Johnson syndrome Increased eosinophils, pathological changes in toxic epidermal necrolysis-soluble Stevens-Johnson syndrome and pleomorphic erythema-type Stevens-Johnson syndrome, dermal vasculature can show significant endothelial edema, the first change It is a vacuole-like change in the dermal epithelial junction, and can be further developed into dermis epidermal separation and subepidermal blister formation. The main inflammatory cells in the dermis can induce a subset of helper T lymphocytes, and the deposition of immunoglobulin and complement is not Significant.

No special auxiliary inspection.

Diagnosis and identification of history-synaptic syndrome

diagnosis

Diagnosis is based on clinical manifestations.

Differential diagnosis

1. Acute eye-skin lesions

Staphylococcal infection scald syndrome is easily confused with toxic epidermal necrolysis and Stevens-Johnson syndrome. Because of the obvious difference in the treatment and prognosis of these two diseases, the differential diagnosis is very important. Staphylococcal infection scald syndrome often occurs. In children, clinically, the skin tenderness of this patient is obvious and the symptoms of systemic toxicity are not obvious. The epidermis of patients with staphylococcal scald syndrome can rapidly regenerate and restore its barrier function. No mucosal damage is found, and exfoliation of the epidermis is limited to On the surface layer, the cause of the disease is due to the release of a certain toxin by Staphylococcus, which can cause damage to the epidermis. For staphylococcal infection, the scald syndrome can be treated with appropriate antibiotics.

Toxic epidermal necrolysis of Stevens-Johnson syndrome is also associated with toxic shock, Kawasaki disease, Leiner's disease and erythroderma secondary to other diseases, in addition to contact dermatitis caused by thermal burns or poisoning.

2. Chronic eye lesions

Toxic epidermal necrolysis Stevens-Johnson syndrome is very similar to scar pemphigoid, sputum adhesion in patients with scar pemphigoid is more common, while Stevens-Johnson syndrome is rare, in toxic epidermal necrolysis In the chronic phase of Stevens-Johnson syndrome, typical skin lesions contribute to its diagnosis. In Stevens-Johnson syndrome, the eye mucosa can present a chronic scar similar to that of scar-like pemphigus, and it lasts for the longest time. For 31 years, mucosal biopsy of patients with scar-like pemphigus can detect linear immunosuppressants of the basement membrane.

The differential diagnosis of chronic ocular lesions also includes chronic keratoconjunctivitis and trachoma caused by bacteria, drugs, allergens, chemical burns, vitamin A deficiency, etc. Careful examination of medical history is helpful for differential diagnosis with Stevens-Johnson syndrome. .

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.