Boil (furuncle) is an acute purulent inflammation of the hair follicle that engulfs the surrounding soft tissues and the adjacent sebaceous gland. The boil begins with the formation of a dense infiltrate, in the center of which a necrotic rod is formed, ending in a pustule. Then there is an opening of the pustule, the removal of the rod along with the purulent contents and the healing of the boil, after which a scar remains on the skin. The diagnosis of a boil includes dermatoscopy, back-seeding of the discharge, blood analysis, examination of the immune system, detection of concomitant diseases and complications. Treatment is carried out locally in accordance with the stages of development of the boil. According to the indications, antibiotic therapy, immunocorrection, and treatment of complications are prescribed.
The popular name of the boil is “boil”. This disease occurs more often in adults, and in men more often than in women. The increase in the incidence of boils occurs in autumn and spring.
Together with ostiofolliculitis, hydradenitis, folliculitis, sycosis and streptococcal impetigo, the boil belongs to pyoderma — a group of dermatological diseases of a purulent-inflammatory nature. If ostiofolliculitis and folliculitis are exclusively a lesion of the hair follicle, then the boil proceeds with the involvement of the surrounding tissues in the purulent process of the follicle and is often a complication of these diseases. Also, the development of a boil can complicate other staphyloderma and streptoderma.
The main cause of the appearance of a boil is a staphylococcal infection. In the course of numerous studies that dermatology constantly conducts, it has been proven that staphylococci are normally present on the surface of human skin. At the same time, only 10% of the total number of staphylococci are pathogenic microorganisms. In patients with boils, this ratio is changed and the number of pathogenic staphylococci often reaches 90%. Such a violation of the microflora of the skin can develop as a result of contamination of the skin, its additional infection or with a decrease in the reactivity of the immune system.
Decreased immunity, in turn, may be due to chronic diseases and infectious processes in the body (tuberculosis, chronic pyelonephritis, bronchitis, hepatitis, sinusitis, tonsillitis, etc.); metabolic disorders (diabetes mellitus, endocrine obesity); long-term therapy with glucocorticosteroids; the use of cytostatics and other medications aimed at suppressing the immune system systems (in patients with lymphoma, stomach cancer, kidney adenocarcinoma, breast cancer, uterine sarcoma and other oncological diseases).
The penetration of staphylococci into the hair sac with the formation of a boil can be facilitated by maceration of the skin with increased sweating and its microtraumation: combs in dermatological diseases with severe itching (eczema, atopic dermatitis, scabies, inguinal epidermophytia, pruritus), scratches, cuts and scuffs. Boils in the nose and auricle can develop as a result of constant exposure to the skin of mucopurulent discharge from the nose or ear in chronic rhinitis, adenoids, sinusitis, otitis media.
The appearance of a boil is possible almost anywhere on the human skin. Most often it occurs where there is friction, sweating or contamination of the skin. These are the face, neck, axillary and groin areas, thighs, buttocks, lower back, chest. In its development, the boil goes through 3 stages: infiltration, suppuration and necrosis, healing. The whole process of its development usually takes no more than 10 days.
The stage of furuncle infiltration begins with the appearance of a bright red infiltration around the mouth of the hair follicle. The infiltrate increases in size (up to 1-3 cm in diameter), thickens, becomes more painful, accompanied by swelling of the surrounding tissues and a tingling sensation. The most pronounced swelling is observed when the boil is located on the face: in the area of the eyelids, lips, cheeks.
The stage of suppuration and necrosis of the boil occurs 3-4 days after its appearance. It is characterized by the formation of a purulent-necrotic rod typical of a boil, emerging on the surface of the skin in the form of a pustule. During this period, there is a rise in body temperature to 38 ° C and pronounced soreness in the area of the boil. Common symptoms of intoxication are possible: malaise, weakness, headache, loss of appetite. At the peak of the clinical picture of the boil, its tire is opened. Pus pours out through the formed hole and the necrotic rod comes out. After that, infiltration, swelling, soreness and general symptoms pass quickly, the healing process begins.
The healing stage of the boil proceeds with the formation of granulation tissue in the crater left after its opening. Within 3-4 days, a scar forms on the site of the boil. At first, it has a noticeable red-blue color, but gradually fades and can become almost invisible.
In some cases, the course of the boil may be erased and not accompanied by the formation of a necrotic rod. When a boil forms in the auricle, its symptoms are joined by intense pain in the ear, radiating into the temporal region and jaw. Sometimes there is a diffuse headache. The boil may block the auditory canal, which is accompanied by hearing impairment.
Despite the apparent simplicity of the disease, even a single boil can cause serious complications. Boils located in the nasolabial triangle and on the mucous membrane of the vestibule of the nose are most often complicated. The development of complications is often facilitated by attempts to squeeze out the boil, its inadequate local treatment, injury during shaving.
According to the localization of the process, all complications of the boil are divided into local (abscess, carbuncle, erysipelas, phlegmon), remote (lymphadenitis, lymphangitis, phlebitis) and general (furunculosis, brain lesions, abscesses in internal organs, sepsis).
Local complications arise due to the fact that the separated boil contains pathogenic staphylococci and can cause infection of other areas of the skin. The fusion of several boils leads to more extensive purulent skin lesions, such as carbuncle, abscess, phlegmon of soft tissues. The multiple nature of boils is regarded as furunculosis.
The transition of infection from the boil to the lymphatic vessels and veins causes the development of lymphangitis, lymphadenitis, phlebitis and thrombophlebitis. The most dangerous is the spread of staphylococcal infection through arterial vessels with the development of metastatic abscesses, pyelonephritis, sepsis. Boils localized on the face can be complicated by arachnoiditis, meningitis, brain abscess.
If signs of skin inflammation are detected, the patient should consult a dermatologist. The doctor will make a diagnosis based on examination and dermatoscopy of the affected area. To determine the etiology of the pathogen, the seeding of the separated boil is performed. Recurrent and multiple boils are an indication for a general examination of the patient with a clinical blood and urine test, blood sugar test, urine back-seeding, pharyngoscopy and rhinoscopy, radiography of the paranasal sinuses, fluorography, ultrasound of the abdominal cavity and kidneys. If necessary, the patient is additionally consulted by an endocrinologist, gastroenterologist, pulmonologist, otolaryngologist and other specialists. The development of complications may require blood culture for sterility, CT of the kidneys, MRI of the brain, lumbar puncture.
The boil must be differentiated from hydradenitis, folliculitis, granuloma with deep trichophytia, nodular erythema, anthrax, tuberculosis of the skin, actinomycosis.
In most cases, boils are limited to local treatment, which is carried out in accordance with the stages of the disease. At the stage of maturation of the boil, ichthyol dressings are applied to it, dry heat is used, UHF therapy. After its opening, bandages are applied with a hypertonic sodium chloride solution, turunda with an ointment containing chloramphenicol in combination with methyluracil. With difficult discharge of the necrotic rod, proteolytic enzymes are shown: trypsin, chymotrypsin. Treatment at the stage of healing of the boil is carried out with antibacterial and healing agents.
In case of multiple and recurrent boils, treatment should include therapy aimed at improving immunity. For this purpose, autohemotherapy, laser and ultraviolet irradiation of blood (UVI), the introduction of gamma globulin, staphylococcal toxoid or vaccine are used. Drug immunomodulatory therapy is prescribed in accordance with the results of the immunogram. Systemic antibiotic therapy is performed in the case of a large, recurrent or complicated boil, as well as when it is localized on the face. Simultaneously with the treatment of the boil, the correction of concomitant diseases and the relief of complications is carried out.
Preventive measures aimed at preventing the appearance of a boil include: skin hygiene, appropriate skin care for hyperhidrosis and increased sebum production, treatment of skin damage with antiseptics, timely and adequate treatment of superficial forms of pyoderma, correction of metabolic disorders and therapy of chronic diseases, a healthy lifestyle that allows you to maintain high immunity.
Prevention of complications is primarily to prevent injury to the boil and the spread of infection. Self-medication is not recommended. It is necessary to consult a dermatologist in a timely manner and comply with his prescriptions.