Psoriasis (scaly lichen) is a chronic non–contagious disease affecting the skin, nails and joints. It is characterized by the appearance of a monomorphic rash on the skin: nodules of bright pink color, covered with silver scales. The elements of the rash can merge into various configurations resembling a geographical map. Accompanied by moderate skin itching. Disease worsens the appearance of the skin, causes psychological discomfort to the patient. When the joints are affected, psoriatic arthritis develops. Generalized pustular form of pregnant women is dangerous, leading to fetal damage and miscarriage.
Psoriasis is a widespread chronic skin disease characterized by a monomorphic rash of flat papules that tend to merge into large plaques, which very quickly become covered with loose silvery-white scales. Disease has a wave–like course, the incidence is 2% of the total population, it is diagnosed equally in both men and women.
The etiology and pathogenesis have not been fully studied, but the research results suggest that hereditary, infectious or neurogenic nature is most likely. The hereditary nature is confirmed by the facts that the incidence is higher in those families in which psoriasis has already been diagnosed, in addition, in monozygotic twins, the incidence concentration is also higher than in other groups. The infectious etiology of psoriasis is reduced to the presence of altered complexes and inclusions, as with a viral infection, but, however, it is not yet possible to identify the virus.
And, today, psoriasis is considered a multifactorial disease with a share of genetic and infectious components. The risk group for the incidence of psoriasis includes people with permanent traumatization of the skin, with the presence of chronic streptococcal skin infections, with disorders of the autonomic and central nervous system, with endocrine disorders, in addition, alcohol abuse increases the likelihood of psoriasis.
The primary element is a single papule of pink or red color, which is covered with a large number of loose silvery-white scales. An important diagnostic sign is the triad: the phenomenon of stearin stain, terminal film and spot bleeding when scales are scraped off.
At the stage of development of pathology, there are few rashes, gradually over the months and even years their number increases. Psoriasis very rarely debuts with intense and generalized rashes, such an onset can be observed after acute infectious diseases, severe neuropsychiatric overloads and after massive drug therapy. If disease has such a beginning, then the rashes are edematous, have a bright red color and quickly spread throughout the body, psoriatic plaques are hyperemic, edematous and often itchy. Papules are localized on the flexor surfaces, especially in the area of the knee and elbow joints, on the trunk and scalp.
The next stage is characterized by the appearance of new, already small elements in the places of combs, injuries and scuffs, this clinical feature is called the Kebner phenomenon. As a result of peripheral growth, newly emerged elements merge with existing ones and form symmetrical plaques or are arranged in the form of lines.
In the third stage of psoriasis, the intensity of peripheral plaque growth decreases, and their boundaries become clearer, the color of the affected skin acquires a bluish hue, intense peeling is observed on the entire surface of the elements. After the final stop of the growth of psoriasis plaques, a pseudoatrophic rim is formed along their periphery – the Voronov rim. In the absence of treatment for psoriasis, plaques thicken, sometimes papillomatous and warty growths can be observed.
In the regression stage, the symptoms begin to fade, while the normalization of the skin goes from the center of the affected surface to the periphery, first peeling disappears, the color of the skin normalizes, and last of all, tissue infiltration disappears. With deep psoriasis lesions and with lesions of thin and loose skin, temporary hypopigmentation may sometimes occur after cleansing the skin from rashes.
Exudative psoriasis differs from the usual by the presence of crusty scales on plaques, which are formed due to impregnation with exudate, there may be wetness in the folds of the body. Patients with diabetes mellitus, people with hypofunctions of the thyroid gland (hypothyroidism) and those with excess body weight fall into the risk group for the incidence of exudative psoriasis. Patients with this form of psoriasis note itching and burning in the affected areas.
Psoriasis, occurring in the seborrheic type, is localized in areas prone to seborrhea. A large amount of dandruff does not allow to diagnose psoriasis in time, as it masks a psoriatic rash. Over time, the areas of the skin affected by psoriasis grow and pass to the skin of the forehead in the form of a “psoriatic crown”.
In people who are engaged in heavy physical labor, psoriasis of the palms and soles is more common. With this type of psoriasis, the main part of the rashes are localized on the palms, there are only isolated areas of rash on the body.
Pustular forms of psoriasis begin with one small bubble, which quickly degenerates into a pustule, and when opened forms a crust. In the future, the process extends to healthy skin in the form of ordinary psoriatic plaques. In severe forms of generalized pustular form, intraepidermal small pustules may appear on the infiltrated skin, which merge to form purulent lakes. Such pustules are not prone to opening and dry up into brown dense crusts. With pustular forms, the lesions are symmetrical, often nail plates are involved in the process.
The arthropathic form of psoriasis is one of the most severe, there is pain without deformity of the joint, but in some cases the joint is deformed, which leads to ankylosis. With psoriatic arthritis, the symptoms from the skin can occur much later than arthralgic phenomena. First of all, small interphalangeal joints are affected, and later large joints and the spine are involved in the process. Due to the gradually developing osteoporosis and destruction of joints, the arthopathic form often ends with the disability of patients.
In addition to skin rashes with psoriasis, vegetodistonic and neuroendocrine disorders are observed, at times of exacerbations, patients note an increase in temperature. Some patients may have asthenic syndrome and muscle atrophy, disorders of internal organs and symptoms of immunodeficiency. If psoriasis progresses, then visceral disorders become more pronounced.
Psoriasis has a seasonal course, most of the relapses are observed in the cold season and very rarely psoriasis worsens in summer. Although recently, mixed forms of psoriasis that recur at any time of the year are being diagnosed more and more often.
The diagnosis is made by dermatologists on the basis of external skin manifestations and patient complaints. Psoriasis is characterized by a psoriatic triad, which includes the phenomenon of stearin stain, the phenomenon of psoriatic film and the phenomenon of blood dew. When scraping even smooth papules, peeling increases, and the surface takes on a resemblance to a stearin stain. With further scraping, after the complete removal of the scales, the thinnest delicate translucent film that covers the entire element is detached. If the exposure continues, the terminal film is rejected and a wet surface is exposed, on which spot bleeding occurs (a drop of blood resembling a dewdrop).
With atypical forms of psoriasis, it is necessary to carry out differential diagnosis with seborrheic eczema, papular form of syphilis and pink lichen. Histological studies reveal hyperkeratosis and the almost complete absence of a granular layer of the dermis, the spiny layer of the dermis is swollen with foci of neutrophil granulocytes, as the volume of such a focus increases, it migrates under the stratum corneum of the dermis and forms microabcesses.
Treatment of psoriasis should be comprehensive, first local medications are used, and course medication is connected when local treatment is ineffective. Compliance with the work and rest regime, hypoallergenic diet, avoidance of physical and emotional stress are of great importance in the therapy of psoriasis.
Sedatives such as tincture of peony and valerian relieve nervous excitability of patients, thereby reducing the release of adrenaline into the blood. Taking a new generation of antihistamines reduces swelling of tissues and prevents exudation. Tavegil, Fenistil, Claritidine, Telfast do not cause drowsiness and have a minimum of side effects, which allows psoriasis patients to lead a habitual lifestyle.
The use of light diuretics in the exudative form of psoriasis reduces exudation and, as a result, reduces the formation of extensive layered crusts. If there are lesions on the part of the joints, then the use of nonsteroidal anti–inflammatory drugs for relieving pain syndrome is indicated – Orthophen, Naproxen and drugs containing ibuprofen as an active substance. If psoriatic disorders in the joints are more serious, then therapeutic joint punctures with intra-articular administration of betamethasone and triamcinolone are used.
With the pustular form of psoriasis, psoriatic nail lesions and erythrodermic psoriasis, aromatic retinoids prescribed for at least a month give a good effect. The use of corticosteroids is justified only in psoriasis crises, prolonged-acting drugs, for example, Dipropsan with subsequent plasmophoresis, can quickly stop a psoriatic crisis.
Such physiotherapeutic procedures as paraffin applications, UV irradiation are indicated for various forms of psoriasis. In the progressive stage of psoriasis, anti-inflammatory ointments are used, if there is an infectious process, then ointments with an antibiotic. Laser treatment of psoriasis and phototherapy are effective. During the transition of psoriasis to the stationary stage, keratolytic ointments and creams are indicated, for example, salicylic, retinoic and Bensalitin. Cryotherapy of psoriatic plaques is performed. If the scalp is affected by psoriasis, then low-percentage sulfur-salicylic ointments are used, since with an increase in the content of salicylic acid, the ointment has a pronounced keratolytic effect.
At the stage of reverse development, reducing ointments are applied topically, gradually increasing their concentration. These are tar, ichthyol and naphthalan ointments or ointments containing these components. Local application of low-concentrated coricosteroid ointments is indicated at all stages of psoriasis. Drugs that modulate the proliferation and differentiation of keratinocytes are a promising direction in modern therapy of psoriasis. During the rehabilitation period, spa treatment with sulfide and radon sources helps to achieve stable and long-term remission.
There is no specific prevention of psoriasis, but after the onset of the disease, it is necessary to take sedatives, conduct vitamin therapy courses and correct diseases that provoke relapses of psoriasis.
Timely therapy of psoriasis allows for long-term remission and is the prevention of complicated forms of the disease.