Psoriasis, commonly known as psoriasis, is a chronic inflammatory skin disease with a long course and a tendency to recur, in some cases almost for life. The disease develops mainly in young adults and has a significant impact on the physical health and mental status of patients. The clinical manifestations are mainly erythema and scaling, and can develop all over the body, with scalp and extremities more common, mostly aggravated in winter.
Although many studies have been conducted on the etiology of the disease, it is still not very clear. At present, it is believed that the occurrence of this disease is not a single cause, but may involve a variety of aspects.
1.Heredity
A significant proportion of patients have a familial history of the disease, and some families have a clear genetic predisposition. It is generally believed that about 30% of the patients have a family history of the disease. The incidence varies greatly in different races. Psoriasis is a polygenic genetic disease in which genetic factors interact with environmental factors and other factors. The presence of certain HLA antigens is significantly higher in patients with this disease. There may be overlap in genetic loci between psoriasis and other diseases (e.g. rheumatoid arthritis, atopic dermatitis, etc.).
2. Infections
Many scholars have confirmed that streptococcal infections are associated with the onset and prolonged course of psoriasis from humoral immunity (anti-streptococcal group), cellular immunity (peripheral blood and lesion T cells), bacterial culture and treatment. In patients with psoriasis, Staphylococcus aureus infection can exacerbate lesions, which is associated with superantigens of Staphylococcus aureus exotoxin. Although the occurrence of the disease is related to viral (such as HIV virus) and fungal (such as Malassezia) infections, the exact mechanism has not been finally confirmed.
3.Immune abnormality
A large number of studies have proved that psoriasis is an immune-mediated inflammatory skin disease, and its pathogenesis is related to inflammatory cell infiltration and inflammatory factors.
4.Endocrine factors
Some female patients’ skin lesions reduce or even disappear after pregnancy, and aggravate after delivery.
5.Other
Psychoneurological factors are related to the onset of psoriasis. Alcohol consumption, smoking, drugs and mental tension may induce psoriasis.
Clinical manifestations
1.Common psoriasis
It is the most common type with acute onset. The typical manifestation is a well-defined erythema of different shapes and sizes, surrounded by an inflammatory red halo. Slightly infiltrated thickening. The surface is covered with multiple layers of silvery white scales. The scales are easy to scrape off, and after scraping the translucent film, small bleeding spots (Auspitz sign) can be seen after scraping the film. The lesions are usually found on the head, sacral area and extensor surfaces of the limbs. Some patients feel varying degrees of itching.
2.Pustular psoriasis
It is less common and divided into generalized type and palmoplantar type. Generalized pustular psoriasis is the appearance of clusters of superficial sterile pustules on erythematous plaques, some of which may fuse to form pus lakes. It can develop all over the body. It is more common in the flexural and folds of the extremities, and the oral mucosa may be involved at the same time. Acute onset or sudden exacerbation is often accompanied by systemic symptoms such as chills, fever, joint pain, general malaise, and increased white blood cell count. Most of the episodes are cyclic and often appear as common psoriatic lesions during remission. Palmoplantar pustulosis lesions are limited to the hands and feet, occurring symmetrically, in good general condition, with stubborn and recurrent disease
3.Erythrodermic psoriasis
Also known as psoriatic exfoliative dermatitis, it is a serious psoriasis. It is often caused by the external use of strong stimulating drugs, long-term application of large amounts of glucocorticoids, too rapid reduction or sudden discontinuation of drugs. It manifests as diffuse flushing, swelling and flaking of the skin all over the body, accompanied by systemic symptoms such as fever, chill and discomfort, enlarged superficial lymph nodes and increased white blood cell count.
4.Arthritic psoriasis
It is also called psoriatic arthritis. Patients with psoriasis also have rheumatoid arthritis-like joint damage, which can involve large and small joints all over the body, but the interphalangeal joint lesions are the most characteristic. The affected joints are red, swollen and painful, and the skin around the joints is often red and swollen. Joint symptoms often worsen or decrease simultaneously with skin symptoms. Blood rheumatoid factor is negative.
Diagnosis
The diagnosis is based on the clinical manifestations of the disease, the characteristics of the lesions, the predilection of the site, and the seasonality.
Treatment
There is no specific treatment for this disease, but it is not incurable. Appropriate symptomatic treatment can control the symptoms. Since this disease is a chronic recurrent disease, many patients need long-term medical treatment, and various therapies have certain adverse effects. The main therapies are combination therapy, alternate therapy, sequential and intermittent therapy, etc.
1.Topical medication
New lesions of small size, as far as possible, the use of topical drugs. The concentration of the drug should be low to high. The choice of which drug to use depends on the nature of the drug itself and the specific condition of the patient.
(1) Vitamin D3 analogues
This class of drugs includes carbotriol and tacalcitol, which are more effective for plaque psoriasis. Carbotriol creams, ointments and lotions (for the head) applied topically twice daily are usually effective within 8 weeks and do not cause dependence with long-term use. The combination of this drug with glucocorticoids or UVB may improve the efficacy. It should be used with caution in patients with bone disease, calcium metabolism disorders and renal insufficiency to avoid causing hypercalcemia.
(2) Glucocorticoids
Topical glucocorticosteroids are still the common therapy for psoriasis. Strong hormones are suitable for the head and palmoplantar area, while weak hormones are suitable for the face and inter-rubbing area. Ointments and creams are commonly used for general areas. For the head, solutions (propylene glycol) and gels must be used. Topical encapsulation therapy can significantly increase the intensity of action.
The effect of glucocorticoids on the lesions is temporary. The initial effect is significant, and sudden discontinuation of the drug often results in a “rebound” phenomenon. For long-term use, intermittent therapy is recommended, i.e., one application every 2-3 days. The use of other drugs (such as vitamin D3 analogues, retinoic acid, etc.) is beneficial to consolidate the efficacy and reduce adverse reactions.
(3) Anthralin
Commonly used in chronic plaque type psoriasis. It can be formulated into ointment, paste and paraffin. The commonly used concentration is 0.05%~1.0%, starting from low concentration and gradually increasing according to the patient’s tolerance. Do not use on the face and inter-rub areas and take care to protect normal skin. The lesions usually begin to fade after 2-3 weeks.
(4) Vitamin A acid
Gel and cream (0.05%~0.1%) applied topically 1 or 2 times a day has good effect on psoriasis. Because of the slow onset of action, it is generally not used as a first-line drug alone. It can be used in combination with glucocorticoids such as clobetasol propionate, and continue to apply tazarotene after skin lesion control, and gradually stop using glucocorticoids. Pregnant women, lactating women and women with recent childbirth requirements are prohibited.
(5) Tar
Commonly used tar, including coal tar, pine distillate, bran distillate and black bean distillate, etc., formulated into a 5% concentration of ointment for external use. Coal tar is more effective for chronic stable psoriasis, scalp psoriasis and palmoplantar psoriasis. It is contraindicated in pregnant women and in pustular and erythrodermic psoriasis. A number of colorless, odorless coal tar preparations are available that are close to the effectiveness of crude products. Soluble coal tar can be used for bathing and coal tar shampoo for shampooing hair. Coal tar spiritus is used for application, which is effective for the treatment of head psoriasis.
(6) Other topical drugs such as immunosuppressants
Such as tacrolimus, pimecrolimus topical treatment, sealing package for treatment of stubborn limited psoriasis. 0.03% ciclopirox ointment, 5% salicylic acid ointment, etc.
2.Internal drugs
(1) Methotrexate (MTX)
MTX can inhibit the proliferation of activated lymphocytes in vivo, weaken the function of CD8 cells and inhibit the chemotaxis of neutrophils. MTX is the standard drug for the systematic treatment of psoriasis, but long-term use can cause extensive fibrosis of the liver and cirrhosis of the liver, so care should be taken when applying it. MTX is suitable for erythrodermic type, arthritic type. pustular type, generalized psoriasis and others who have poor results with conventional treatment. Avoid use in the presence of abnormal liver and kidney function, pregnancy or lactation, reduced white blood cell count, active infectious diseases, alcoholism, immunodeficiency and other serious diseases.
(2) Retinoic acid
Retinoids can regulate epidermal proliferation and differentiation as well as immune function, etc. They are used for generalized pustular psoriasis, erythrodermic psoriasis and severe plaque psoriasis, and have satisfactory efficacy when taken alone or in combination with other therapies. The main side effects of Avastin are teratogenic fetuses. Studies have shown that Avastin is still measured in the urine 2 years after stopping taking it, and some Avastin can be converted into Avastin, so women of childbearing age should take contraceptive measures within 2 years after stopping the drug: dry lips, eyes and nasal mucous membranes, diffuse skin desquamation and hair loss occur during the drug. Elevated blood lipids may occur with long-term use. Liver damage, etc., but can recover after stopping the drug.
(3) Glucocorticoids
This kind of medicine should not be used routinely and systematically for psoriasis, because the effect is not great, and the symptoms are even more serious than before after stopping the medicine, and may even induce acute pustular psoriasis or erythrodermic psoriasis. However, because of the “anti-inflammatory” effect of glucocorticoids, they can be used with caution for erythrodermic, arthritic and generalized pustular psoriasis when other therapies (such as MTX) are not effective or are contraindicated.
(4) Immunotherapy and biologic therapy
Immunosuppressive agents such as cyclosporine A, tacrolimus and mycophenolate have good efficacy when used in severe psoriasis. The application of some new biological agents, such as cytokine blocker etanercept (Ixep), is a new development in the treatment of psoriasis, but it is expensive and has adverse effects, so its clinical application needs further observation.
(5) Antibiotics
The occurrence and recurrence of some psoriasis are related to micro-object infections such as bacteria, fungi and viruses, especially acute punctate psoriasis is often accompanied by acute tonsillitis or upper respiratory tract infection, and these cases can be treated with penicillin and cephalosporins with good efficacy. Certain antibiotics also have immunomodulatory effects, such as erythromycin. Some patients with seborrheic areas have a large number of Malassezia bacteria, can apply ketoconazole lotion treatment.
3.Physical therapy
UV light, photochemotherapy (PUMA), broad-spectrum medium-wave UVB therapy (BB-UVB), narrow-spectrum medium-wave UVB therapy (NB-UVB), hydrotherapy can be applied.
4.Chinese herbal medicine treatment
Chinese herbal medicine and Chinese patent medicines such as compound Qing Dai pill, Lei Gong Tang, compound Dan Shen tablet can be applied.