Lupus vulgaris is a common form of caseous-necrotic tuberculous skin lesion, affecting mainly the face and upper half of the trunk. It is manifested by the formation of tubercles (lupus) with ulceration, gradually merging together, partial or complete disfigurement of the face. It is diagnosed by dermatological examination, examination of the separated skin (microscopy, PCR), specific tests. Treatment is carried out with anti-tuberculosis antibiotics, immunostimulants and other auxiliary means.
ICD 10
A18.4 Tuberculosis of the skin and subcutaneous tissue
General information
Lupus vulgaris is the most common, chronically occurring form of local tuberculosis with a tendency to tissue melting. According to official statistics, the average detection rate of vulgar lupus is 0.43 patients per 100,000 population (4.1% of the frequency of all extrapulmonary tuberculosis). Children and adolescents are susceptible to the disease, people of mature age suffer less often. The disease is more often found in women. Lupoid tuberculosis has a long recurrent course and without treatment can progress throughout life.
Causes
The causative agent of the disease is a gram-positive microorganism (Koch’s wand), not prone to the formation of spores, but having high resistance to chemical agents and environmental factors. In most cases, lupus is caused by M. tuberculosis, sometimes by M. bovis. Bacteria enter the skin and mucous membranes endogenously with the flow of blood or lymphatic fluid from other foci of tuberculosis infection (lung tissue, bones, joints, peripheral lymph nodes) present in the body. Cases of exogenous infection from other persons through damaged skin are much less common with close contact with a bacterial separator.
The probability of developing tuberculous lesions of the skin increases in the absence of exposure to sunlight (insolation). The direct effect of ultraviolet radiation kills Mycobacterium tuberculosis within a few minutes. Risk factors are also considered injuries, hypothermia, which reduce the activity of human immunity and contribute to the activation of latent infection. Predisposition to allergic reactions (urticaria, Quincke’s edema) increases the likelihood of a more severe course of the disease.
Pathogenesis
After the pathogen enters the skin from the primary focus by hematogenic or lymphogenic pathway, a lupoma the size of a pinhead is formed. It is the primary morphological element of vulgar lupus and is a cluster of small tuberculous tubercles. With massive infection of damaged skin by contact, an infiltration occurs that resembles a focus of Rut, accompanied by lymphadenitis and lymphangoitis.
Histological examination reveals lupomas from epitheliod cells and Langhans cells in the dermis, a zone of lymphocytes and plasmocytes is located on the periphery. Curd necrosis in the tubercles is absent or expressed slightly. Altered, deformed vessels are detected (up to complete overgrowth). Excessive thickening of the stratum corneum, hyperpigmentation, and papilloma formation occur in the epidermis.
Classification
Depending on the clinical picture of the disease, several forms of lupus are distinguished, which differ in the intensity of manifestations and external signs. There are: flat, ulcerative, psoriasiform, ptiriaziform, warty, tumor-like and other less common varieties. Often ulcerative and flat forms can be combined with each other.
- Flat. Individual lupomas merge with each other, forming a lesion. It increases as a result of the appearance of new tubercles in the peripheral parts. The surface of the hearth is smooth, peeling is insignificant or absent.
- Ulcerative. Occurs with massive ulceration of the surface of the lupus. The ulcers are shallow, bleed when touched. Deformities of the cartilage of the nose and auricle often develop, which contributes to the disfigurement of the face.
- Psoriasis form. Lupoma looks like a plaque of psoriasis. On the surface there are gray-white scales with peeling, the skin on the periphery is hyperemic.
- Ptiriaziform. It is characterized by bran-like large peeling in the affected area.
- Warty. Typically, the formation of growths of a whitish color, outwardly resembling warts.
- Tumor-like. It represents several merged tubercles. They form a large soft-elastic tumor, prone to decay or the formation of ulcers.
There are four stages in the clinical course of the lupus process. Each has flow characteristics that determine the severity of the patient’s condition:
- Infiltrative. There is swelling, hyperemia of tissues, lupomas are not pronounced.
- Tubercular. Small bumps form, which connect and resemble warty vegetation.
- Ulcerative (may be absent). Bleeding ulcers appear on top of the lupomas, papillomas often occur.
- Scarring. If the process has not passed the stage of ulceration, the scars are smooth and shiny. After epithelization of ulcers, dense deforming scars are formed.
Symptoms
The disease develops gradually: at first, tubercles 1-8 mm in size form in the dermis, having yellow, brown, brown, gray coloration. Lupomas have a dough-like consistency, a smooth shiny surface, where peeling subsequently occurs. The tubercles are always painless, they pour out in the amount of several pieces at a distance from each other, gradually merging: a stagnant area appears along the periphery. The pathological process is most often localized in the area of the auricles, nose, cheekbones, upper lip, can move to the front surface of the neck and shoulders, affect the mucous membranes with the formation of rough scars.
Lupomas connect with each other, increase in size, forming uneven plaques or tumor-like foci. Due to necrosis processes, deep ulcers appear in the center. With a particularly severe course of lupus in patients with weakened immunity, not only the skin, but also cartilage tissues are involved in the destruction. When the nasal septum is destroyed, it resembles a pointed shortened beak of a bird. The sense of smell is impaired, the respiratory function suffers.
Due to the destruction, the eyelids turn out, the mouth opening decreases in size, the cartilages of the auricles become thinner and break off. The defeat of the mucous membrane of the oral cavity leads to a violation of the chewing and swallowing function: patients often choke, hard to digest solid food. When the vocal cords are involved in the pathological process, the voice may change: it becomes deaf, hoarse.
Within 4-6 weeks, healing of damaged tissues occurs. After the completion of the active ulcerative process, flat tender scars resembling papyrus form on the surface of the skin.
Complications
The resulting scars cause contractures, restrict the movement of facial muscles: this causes a complete or partial loss of articulatory abilities (with damage to the face, oral cavity, larynx). In the absence of timely treatment, tuberculosis lupus can be joined by a secondary infection – erysipelas. If the inflammatory process passes to the lymphatic vessels, lymphangitis develops. In 4% of all cases, basal cell carcinoma occurs against the background of lupus vulgaris.
Diagnostics
Diagnosis of lupus vulgaris is carried out on the basis of general examination data and physical examinations. When detecting the disease, the cooperation of a dermatologist and a phthisiologist is necessary, since it is necessary to detect and treat the primary focus of tuberculosis. For diagnostic search , the most informative:
- Physical examination. With its help, the prevalence of tubercles, their color, consistency is established. As a result of the death of elastin fibers when probing the plaque with a button probe, it plunges into it without resistance (Pospelov’s symptom). If the lupoma is pressed with a slide, the skin is exsanguinated, and the bumps themselves take the form of yellow-brown spots (a sign of Gentchinson or the phenomenon of apple jelly).
- Laboratory diagnostics of the pathogen. The biological material (skin discharge) is stained according to Zil-Nielsen and subsequent microscopic examination with an immersion system is carried out. Mycobacteria have the appearance of red sticks on a blue background. Polymerase chain reaction in 5-7 hours makes it possible to determine a small amount of mycobacterium DNA in the test sample.
- Conducting tuberculin tests. The Mantoux test and Diaskintest are evaluated based on an increase in the size of the infiltrate and papule of more than 5 mm, indicating infection. Scarification samples (Pirke, graduated sample) are used less often: they show a positive result for the presence of mycobacteria.
- Quantiferon test. Detects gamma interferon in the blood, which appears in the human body in response to the introduction of mycobacteria. The method has high specificity (99.1%) and sensitivity (89%). Its analogue is T-SPOT.TB test that detects sensitized T-lymphocytes.
- Instrumental methods. Chest x-ray is performed in a direct and lateral projection, revealing the primary focus of tuberculosis in the lungs. Damage to bones and other internal organs can be detected by CT or MRI.
In the general blood test for lupus vulgaris, there is a decrease in the level of leukocytes associated with the underlying disease. A significant decrease in lymphocytes and an increase in ESR are unfavorable prognostic signs. In order to assess the reactivity of the body, an immunogram is performed. Differential diagnosis is carried out with lupus erythematosus, tuberculous syphilis, tuberculopodopa leprosy.
Treatment
In modern dermatology, the use of complex therapies is provided. Patients with lupus vulgaris should be treated in a specialized dispensary in compliance with the ward or general regime. A diet with a restriction of salt, fast carbohydrates is prescribed, food rich in proteins is recommended for consumption. You should also completely abandon bad habits (they contribute to a decrease in immunity). Conservative therapy includes:
- Anti-tuberculosis drugs (chemotherapy). For this, the first line of drugs is used (isoniazid, rifampicin, rifabutin, pyrazinamide, ethambutol, streptomycin), dosages are selected individually by the phthisiologist. Other lines are used in the development of drug resistance.
- Auxiliary therapy. To reduce the side effects of anti-tuberculosis antibiotics, symptomatic drugs are prescribed: antioxidants, immunostimulants, glucocorticoids, vitamins, anabolics, hepatoprotectors.
- Physiotherapy procedures. Especially effective is ultraviolet irradiation of the outer integuments, which stimulates regeneration processes, causes the death of mycobacteria, reduces the likelihood of complications. Among other techniques, medicinal electrophoresis with antibacterial drugs, laser therapy, inductothermy, therapeutic gymnastics, UHF therapy are often used.
Surgical removal of ulcerated areas of the skin and cartilage is carried out only at the risk of secondary infection. With severe disfigurement, plastic surgeries for skin grafts and cartilage tissues can be used to restore the appearance later. With their help, the integrity of the nasal septum is restored, auricles are formed, deforming scars are excised.
Prognosis and prevention
Lupus vulgaris is a chronic disease. With timely detection and treatment, the prognosis is favorable. The recurrence of the disease is observed only in case of violation of the treatment regimen or the development of drug resistance in mycobacteria. Prevention of lupus vulgaris is reduced to the treatment of the underlying disease, compliance with the rules of personal safety in contact with infected people (the use of gloves, masks) and strengthening immunity.
