Iododerma is one of the forms of drug toxicoderma caused by increased intake of iodine or its compounds into the body or the presence of idiosyncrasy to them in the patient. Symptoms of this condition are the development of rashes of various types on the skin of the face, trunk, limbs, depending on the form of the disease. Diagnosis of the iododerm includes identification of the source of iodine intake into the body (study of the patient’s medical history and anamnesis), histological examination of tissues from pathological foci. Treatment is reduced to the abolition of the use of iodine preparations, acceleration of its excretion from the body, prevention of secondary infectious lesions of the skin.
Iododerma is a dermatological condition caused by uncontrolled excessive use of iodine preparations or the presence of hypersensitivity to its compounds. This condition has been known in medicine for a long time, but only at the end of the XIX century it was possible to reliably link characteristic skin lesions with the use of iodine preparations. This chemical element-halogen is used in medicine in its pure form (alcohol antiseptic solution) and in the form of compounds for the treatment of thyroid diseases, atherosclerosis. In addition, it is part of numerous radiopaque preparations. It is noted that the most common development of the iododerm is observed after the use of potassium iodide. The disease is more common in men. Predisposing factors to its appearance are lesions of the heart, kidneys, some endocrine diseases and immunological disorders.
When using increased doses of iodine compounds, its accumulation (cumulation) occurs in various tissues, including in the skin. Iododerma develops in cases where there is a more or less pronounced sensitivity to this element – histological studies confirm the development of leukocyte infiltration of the skin in this condition. As a result, immunological aseptic inflammation develops, which is the main factor of tissue damage. The exact mechanism of the pathogenesis of iododerma is currently unknown, there are several basic theories on this, but none of them provides a comprehensive explanation of all manifestations and forms of this disease. Therefore, some dermatologists suggest the presence of several variants of the development of such disorders.
Most cases of iododerma occur against the background of prolonged use of iodine preparations, frequent use of iodine-containing contrasts in X-ray studies. In this situation, apparently, there really are processes of accumulation of this element in the skin tissues with the subsequent development of inflammation. In other, rarer variants of iododerma, the development of symptoms may occur after a single use of contrast or taking iodine preparations and even due to its application to the surface of the skin during antiseptic treatment. In this case, there is probably a strong hypersensitivity to iodine, and the mechanism of development of disorders should be completely different.
In its manifestations, iododerma is similar to many other drug-induced toxicoderma, in particular, with bromoderma. Against the background of taking iodine preparations, the patient has rashes of various structures with predominant localization on the skin of the face, auricles, neck, upper extremities. Depending on the clinical form of the iododerm, rashes can be represented by erythema, papules, vesicles, pustules, erosions and ulcers. Sometimes the skin manifestations of the disease can take on the character of urticaria and be accompanied by severe itching of the skin. In some cases, iodine dermis rashes on different parts of the body may have a different character. In dermatology, there are four types of clinical manifestations of this disease: simple, bullous, tuberous iododerma and iodide acne.
Simple iododerma is characterized by the development of rashes on the face, neck and extremities of various types – erythematous, papular, in the form of urticaria. Most often, this form of the disease occurs after the use of iodine-containing radiopaque preparations or a single dose of a significant dose of potassium iodide and other compounds of this element. Rashes are accompanied by pronounced itching, but after a few hours or days in the absence of repeated intake of provoking substances, they spontaneously resolve without any traces.
Iodic acne, or iodic acne, is a more pronounced form of iododerma, the cause of which is long–term therapy with drugs based on this element. It is characterized by the appearance on the face and neck of nodules and pustules up to 5 millimeters in diameter, surrounded by a pronounced inflammatory roller. If you continue taking iodine preparations, it is possible to develop new rashes or the occurrence of more severe forms of iododerma. After the pustules heal, red scars may remain in their place.
Bullous iododerma is a rather serious form of the disease, which is characterized by the development of tense blisters on the skin of the face or neck with a diameter of 4-12 millimeters, filled with serous or hemorrhagic contents. They can fuse together, forming lumpy foci of irregular shape. With the further development of the bullous iododerm, the bubbles are opened, in place of which a deep ulcer is formed, a dense nodule begins to form in its center, which eventually softens and builds up. The healing of such skin lesions takes a very long time and leaves behind noticeable scars.
Tuberous iododerma is the most severe, but rare form of the disease, in which a small bubble is first formed on the surface of the skin, which quickly turns into a pustule. It also does not persist for a long time and transforms into a tumor or a sharply inflamed plaque with a diameter of up to 5 centimeters. Numerous vesicles with hemorrhagic or purulent contents are observed around this focus of tuberous iododerm. The consistency of the tumor or plaque is soft, in the future they can ulcerate, healing takes a very long time. At the site of the pathological focus of the iododerm, a noticeable scar is formed.
In some cases, the development of skin symptoms of iododerma may be preceded by fever, vomiting, broken and tired condition. In the case of the development of such nonspecific manifestations against the background of taking iodine preparations, their use should be immediately discontinued to prevent skin lesions. A common complication of iododerma is a secondary bacterial infection of the skin.
Iododerma is diagnosed by identifying the source of iodine compounds entering the body (examination of the patient’s outpatient card, questioning), examination of skin manifestations, in some cases, a skin biopsy and histological examination of the affected tissues are performed. As a rule, the patient’s medical history identifies diseases for the treatment of which iodine compounds are used (thyroid lesions, for example), X-ray contrast studies, cases of earlier unusual reactions to iodine. All this indicates that the patient has hypersensitivity to this element, and the development of dermatological symptoms after taking drugs based on it indicates iododerma.
The histological picture of the skin with simple iododerma can be reduced to dilation of blood vessels and minor neutrophil infiltration of tissues. With bullous and tuberous forms, pronounced leukocyte infiltration (represented mainly by neutrophils), areas of dermal necrosis, and sometimes intraepidermal abscesses are observed at the initial stages. In the future, lymphocytes and histiocytes appear in the focus of the iododerm, hyperplasia of skin tissues is possible, outwardly resembling a picture of carcinoma. Differential diagnosis of the disease should be carried out with allergic urticaria (simple iododerma), bromoderma, tuberculous and syphilitic skin lesions, malignant neoplasms.
All treatment of iododerma is aimed at reducing the sensitivity of the body to iodine compounds, accelerating its excretion and preventing complications. A prerequisite for starting therapy is the complete cessation of taking iodine preparations and a ban on radiopaque studies with their use. Desensitizing therapy includes the use of antihistamines (for example, chloropyramine) and calcium chloride, but it is not effective in all cases of iododerma. Antihistamines work best in eliminating the symptoms of a simple form of this disease.
To accelerate the excretion of iodine from the body, drip infusions of saline are prescribed, increased amounts of table salt are introduced into the diet (up to 10-20 grams per day), diuretics are sometimes used. To prevent infectious complications of the iododerm from the skin, antiseptic ointments and solutions are locally used, sterile dressings are applied. In severe cases, it is necessary to use corticosteroids, and with symptoms of bacterial infection – antibiotics and antimicrobials. Ultraviolet irradiation of the affected areas of the skin also has a beneficial effect with iododerm.
Prognosis and prevention
In most cases, the prognosis of the iododerma regarding recovery is favorable, the cancellation of iodine preparations, desensitizing therapy and the removal of this element from the body contribute to the rapid disappearance of symptoms. However, in severe cases, especially with bullous and tuberous forms of the disease, noticeable scars may remain on the skin. Given that the favorite localization of such rashes is the face, scars can become a significant cosmetic defect. For the prevention of iododerma, iodine preparations should not be used without a doctor’s recommendation, and if necessary, their long-term use should be provided in the course of withdrawal periods for detoxification of the body.