Sarcoidosis skin is a specific granulomatous lesion of the skin that occurs with systemic sarcoidosis or as an isolated form. Sarcoid elements are represented by papules, nodules, plaques, ulcers. Foci of alopecia, hypo- and hyperpigmentation, nodular erythema, nail plate lesions may occur. The diagnosis is confirmed by skin biopsy data. Additional methods include blood biochemistry, X-ray and CT of the thoracic cavity, FER, ultrasound. Topical, intraocular and systemic glucocorticosteroids, TNF-α inhibitors are used as therapeutic agents.
D86.3 Sarcoidosis skin
Cutaneous sarcoidosis develops in 10-30% of patients with the systemic form of Benier-Beck-Schaumann disease. It can occur in isolation, but is more often combined with damage to other organs: lungs, intracoracic lymph nodes, eyes, spleen, nervous system, heart, musculoskeletal system. Systemic sarcoidosis is more often registered in the population of the Nordic countries, neurosarcoidosis and cardiosarcoidosis are more common among Japanese, skin sarcoidosis is more common among African Americans. Mostly women over 40 years old are ill.
Sarcoidosis is a disease of polyethological nature, in the development of which immune mechanisms are involved. It is assumed that the formation of sarcoid granulomas in the skin and other organs is initiated by certain antigens (infectious, chemical, medicinal).
Immunopathological reactions develop in individuals with a genetic predisposition. The association of sarcoidosis skin with the carrier of certain HLA-alleles, single-nucleotide polymorphism in a number of genes, mutations in the genes ZNF184, ADCY3, MMP9, FCGR3A, etc. was traced. Observations of sarcoidosis in members of the same family are described. Among the triggers of the disease studied to date , the main role is assigned to the following factors:
1 Occupational hazards. The frequency of sarcoidosis is significantly higher in persons in contact with various chemical agents, including insecticides, organic dust, building materials, gorenje products, metals and minerals (zirconium, beryllium, silicon). These are workers of woodworking, paper, leather, furniture, electroplating industries, firefighters, drivers, welders, builders, medical workers.
2 Infections. Among the known infectious antigens that trigger sarcoidic reactions are herpes and hepatitis C viruses, mycoplasma, chlamydia, mycobacteria, borrelia, propionibacteria acne. Granulomatous changes in the skin may occur due to contact with mold fungi.
3 Medications. There are cases of sarcoidosis of the lungs and skin after the use of interferon alpha inducers of interferon, as well as regression of symptoms after the withdrawal of these drugs. Identical reactions after administration of hyaluronic acid are described.
4 Psychogenic reactions. There are cases when the trigger factor for the development of the disease was severe life situations (divorce from a spouse, death of a loved one, constant stress).
Various antigenic factors (bacterial, viral, medicinal, chemical) cause immune reactions, during which activated macrophages and T-lymphocytes stimulate the formation of anti-inflammatory cytokines, including IFN-γ, TNF-α, IL-1, IL-2, GM-CSF, etc. Cytokines promote the migration of monocytes and macrophages to the focus of inflammation, their subsequent differentiation into epithelioid histiocytes.
Further transformation of epithelioid cells occurs by their fusion with the formation of multinucleated giant Pirogov-Langhans cells. Gradually, the foci of inflammation are fibrosed and delimited, sarcoid granulomas are formed in the affected tissues. Morphologically, granulomas are represented by epithelioid cells, macrophages, Langhans cells with Schaumann bodies in the cytoplasm – in the center, a ring of fibroblasts and lymphocytes – on the periphery.
In clinical dermatology, about 20 different forms of skin sarcoidosis have been described, which have their own clinical manifestations, concomitant lesions and prognosis. Pathology can occur in typical and atypical variants. Typical forms of cutaneous sarcoidosis include:
1 Beck’s sarcoidosis. It occurs most often. It has 3 forms: small-nodular, large-nodular and diffuse-infiltrative.
2 Benier-Tenneson’s chills lupus. A rare type of cutaneous sarcoidosis (2.7%) with an unfavorable course is associated with progressive lung sarcoidosis.
3 Subcutaneous sarcoid of Darye-Russi. Develops in 1.5-6.0% of patients with systemic sarcoidosis. It is characterized by a lesion of subcutaneous fat.
4 Broca’s angiolupoid-Potrie. It occurs in isolated cases, has a relatively benign course.
There may be mixed varieties of skin sarcoidosis: large- and small-nodular, large-nodular and deep subcutaneous sarcoid, small-nodular and angiolupoid, etc. Atypical forms of skin lesions, as a rule, accompany visceral sarcoidosis. There are the following atypical variants of pathology:
- angiomatous , etc .
Skin lesions in sarcoidosis can be nonspecific (without the formation of sarcoid granulomas) and specific. Nonspecific symptoms are represented by nodular erythema, erythema multiforme, calcification of the skin. Typical specific variants of sarcoidosis skin are described below.
Rashes have the form of small nodules (2-7 mm), large nodes (0.7-1.0 cm) or infiltrates (5-6 cm) protruding above the skin level. The elements are localized on the face, the upper third of the trunk. They have a smooth surface, a brown or bluish hue, a dense elastic consistency, do not merge with each other. During diascopy, a positive phenomenon of “specks of dust” (dot specks) is revealed. After the resolution of rashes, transient pigmentation or small atrophic scars remain on the skin.
Benier-Tenneson’s chilling lupus
It is a combination of diffuse-infiltrative and large-nodular sarcoidosis. Rashes affect the skin of the nose, cheeks, auricles, sometimes found on the back of the hands, nasal and oral mucosa. The lesion on the face resembles a butterfly, as in systemic lupus erythematosus.
The elements of sarcoidosis are represented by plaques of red-brown or red-purple color. Multiple telangiectasias are visible on the surface of the plaques. They exist for a long time with an outcome in cicatricial atrophy of the skin. This variant of sarcoidosis skin is often combined with bone damage.
Subcutaneous sarcoid of Darye-Russi
It refers to deep sarcoid lesions affecting subcutaneous tissue. The main elements are large (up to 5 cm in diameter) nodes located in the hypoderm. They are localized in the area of the shoulder blades, on the abdomen, side surfaces of the trunk, thighs. They can fuse with the skin (a symptom of “orange peel”) or merge with each other (the phenomenon of “cobblestone pavement”).
The telangiectatic form of sarcoidosis is characterized by the presence of single mildly elastic plaques 2-3 cm in size on the skin of the forehead or nose. The elements have a stagnant bluish-red surface, covered with numerous telangiectasias.
Cutaneous sarcoidosis is associated with the presence of cosmetic defects, a decrease in the quality of life, the development of side effects from hormone therapy. With the long-term course of chilling lupus with the defeat of the fingers, trophic disorders, ulcerative defects develop, after scarring of which contractures are formed. Sometimes there is destruction of cartilage and bones, mutation of the fingers of the hands. Nasopharyngeal lesion can be complicated by perforation of the nasal septum.
Skin reactions are often combined with visceral lesions, against which systemic complications develop from the lungs (fibrosis, pulmonary hypertension), the organ of vision (granulomatous uveitis, iridocyclitis), kidneys (ICD, CRF), heart (myocarditis, arrhythmias, HF), nervous system (sensitivity disorders, ataxia, Bell’s palsy, cognitive disorders).
Sarcoidosis skin can precede the development of systemic manifestations, so its early diagnosis is important in preventing visceral lesions. To assess skin changes, the patient is examined by a dermatologist, a consultation of a phthisiologist (pulmonologist) is also indicated, if necessary – a cardiologist, neurologist, ophthalmologist. To confirm the diagnosis and identify concomitant lesions,:
- Biopsy. The diagnosis of sarcoidosis skin is confirmed by morphological examination of biopsies of altered skin. Sarcoid granulomas contain Pirogov-Langhans cells with Schauman inclusions, while, unlike tuberculous granulomas, they lack MBT and caseous decay. To verify changes in organs, diagnostic thoracoscopy is performed with a biopsy of the VGLU, lung tissue.
- Special samples. In 95% of patients, tuberculin tests are negative (rarely – weakly positive or positive). The Kweim test with intradermal injection of a suspension of the contents of sarcoid foci in most cases demonstrates a positive reaction – at the injection site after 3-4 weeks. a cutaneous granuloma is formed.
- Instrumental research. Mandatory diagnostic stages are CT of the chest, X-ray of the hands and feet, ultrasound of the liver and kidneys. To detect cardiac disorders, an ECG, ultrasound of the heart is necessary.
- Laboratory tests. Blood test in systemic sarcoidosis is characterized by anemia, leukopenia and lymphopenia, acceleration of ESR. Biochemical changes include hypercalcemia, an increase in alkaline phosphatase, total protein and gamma globulins. Hypercalciuria is noted in the urine analysis.
Different types of sarcoidosis differentiate with other specific and non-specific skin lesions in the following pathologies:
Treatment of skin sarcoidosis
The first-line drugs for the treatment of sarcoidosis of any localization are corticosteroids. In isolated or concomitant skin lesions, they are prescribed topically in the form of ointments and creams, intraocular injections. In case of chilling lupus, the elements are locally affected by a CO2 laser, liquid nitrogen, and PUVA therapy is performed in the erythrodermic form.
With an active and widespread skin process, its combination with organ pathology, oral administration of corticosteroids, injections / infusions of corticosteroids is indicated. Cytostatics, antimalarial drugs are also used as monotherapy or in combination with GCS (to reduce the dose of the latter). In some cases, tetracycline derivatives are effective.
A promising method is the use of monoclinal antibodies to TNF-α. Antioxidants, vitamins, angioprotectors, and potassium-containing drugs play an auxiliary role in the treatment of sarcoidosis skin.
Prognosis and prevention
Sarcoidosis skin does not threaten the patient’s life, long-term remission is achieved when following the recommendations of doctors. Spontaneous regression of rashes is possible. Since patients with sarcoidosis skin have an increased risk of developing systemic sarcoidosis, they should be under the dispensary supervision of a general practitioner or pulmonologist, undergo regular clinical and instrumental examination. In order to prevent cutaneous sarcoidosis, it is advisable to limit contact with harmful substances at home and at work, avoid nervous shocks, infections, uncontrolled drug intake.