Occupational Eczema

Occupational eczema follows a chronic and protracted course and often recurs on exposure not only to occupational, but to everyday irritants. At first the lesions are localized on skin areas, which come in touch with the allergen, but later they spread to other remote skin areas. The involved skin areas thicken gradually and coarsen, lichenification takes place, and fissures appear. The recurrences developing from time to time are marked by exacerbation of the process, intensification of inflammation, appearance of swelling and weeping, and intensification of itching.

Occupational eczema is predominantly localized on exposed skin areas subject to the effect of occupational irritants, develops in patients with occupational allergic dermatitis, as a rule, and is manifested by erythema, vesiculation, papular eruptions, weeping, and itching. Cessation of contact of the skin with the allergen does not lead to a rapid cure, as the case is with dermatitis. Skin tests demonstrate in most of these patients polyvalent sensitization instead of the earlier monovalent type.

Immunoallergic skin tests with occupational allergens, which are carried out in vitro, may be positive for several years.

Occupational eczema may be induced by some dyes, the salts of nickel and chromium, particularly sixvalent chromium contained in cement, and also by paraphenylenediamine, formaldehyde, turpentine, bakelite adhesive, artificial epoxy resins, etc. It usually develops against the background of occupational allergic dermatitis. In distinction from dermatitis, its treatment involves the same difficulties that are encountered in the treatment of non-occupational eczemas.

Histopathology. The presence of foci of spongiosis in the epidermal Malpighian layer is typical of the acute period of eczema. The spongiosis is characterized by oedema mainly of the prickle-cell layer, separation and tearing off of the cells of this layer, and the formation of small often multilobate cavities directly under the horny layer. Parakeratosis is seen in the horny layer. The papillary layer of the dermis is marked by dilation of vessels, the formation of a lymphocytic-histiocytic infiltrate around them, and oedema of the connective tissue. Acanthosis, the formation of parakeratotic scales and crusts, and a more pronounced infiltraie of the dermis are characteristic of chronic eczema.

Treatment of eczemas

The application of a complex of sedatives, antihistaminics, and (in cases of a torpid eczematous process) low doses of corticosteroids is most expedient and pathogenetically substantiated in the management of patients with eczema. In simultaneous use of these methods, an effect is produced both on the central parts of the nervous system and on the mechanisms which determine the development of allergic inflammatory reactions.

Hyposensitization therapy also includes medication with calcium preparations and sodium hyposulphite in combination with antihistaminics.

Diuretics (hydrochlorothiazide, furocemide, mullein decoction) are taken in the morning the first four or five days to reduce tissue oedema. Magnesium sulphate causes a hyposensitizing, sedative and hypotensive effect, reduces tissue oedema and inflammatory potential, and improves the filtration function of the kidney.

Sedatives are prescribed: preparations of bromine, Valerian, leonorus, tranquillizers and neuroleptics (Elenium, Amizyl, Diazepam, Teralen, etc.).

Corticosteroids (prednisolone, methylprednisolone, dexamethasone, triamcinolone, 1 tablet taken three or four times a day for six to eight days) are prescribed to cause an effect on the allergic and inflammatory phases in severe forms of the disease if there are no contraindications and when other measures prove ineffective.

With abatement of the inflammatory and allergic signs, the dose is gradually reduced to half a tablet given two or three times a day (at first daily, and then every other day) and then corticosteroids are discontinued.

Whenever indicated, vitamins are prescribed (A, B₁ B₂, B₆, B₁₂, B₁₅, E, K, and C, folic, nicotinic, orotic acids, calcium Pangamate and pantothenate).

Antibiotic therapy produces a good effect in microbial eczema and when pyogenic infection develops in other forms of eczema.

Of no small importance is the treatment of focal infection, epidermophytosis which sensitizes the body, diseases of the gastrointestinal tract, liver and pancreas, endocrine disorders, and helminthiasis.

Treatment of eczema in children begins with the arrangement of a diet regimen because the alimentary factors play an important role in the origin and development of eczemas in them. Cow's milk is replaced by yoghourt. The amount of liquids, table salt, and carbohydrates is reduced by 10-20 per cent because they contribute to the retention of water in the tissues and therefore intensify the degree of skin inflammatory reaction. Proper artificial feeding of infants and regular meals for the nursing mother are important.

Rational nutrition and diet play an essential role in the management of eczema in adults and children: extractive substances, citrus fruits, mushrooms, meat broth, and spicy foods are restricted or completely removed from the diet. Milk and vegetables produce good results.

Spa therapy is advisable after abatement of the acute stage. Treatment at hydrogen-sulphide health resorts, sea bathing, and heliotherapy are indicated.

Acupuncture is prescribed in eczema marked by severe itching. Applications of ozocerite, paraffin, and therapeutic muds are recommended in severe infiltration with lichenification.

The external treatment of eczema depends on the degree of the inflammatory process. The scales and crusts should be first removed from the foci. For this purpose dressings with sterile gauze soaked in vegetable oil are applied to the lesions. The weeping stages of eczema respond well to treatment with cooled lotions containing 2 per cent boric acid, 0.25 per cent silver nitrate, 0.5 per cent resorcinol, etc. It is not advisable to treat infants with lotions containing resorcinol and boric acid, otherwise toxicosis may develop. After weeping ceases, corticosteroid ointments are used (prednisolone, Depersolone, Locacorten, Flucinar, Ftorokort, Ultralan, Celestoderm). Bearing in mind that the hormones might be absorbed by the skin, particularly by areas exposed as the result of the eczematous process, steroids should be applied to limited skin areas in children, or they should be mixed with Unna's cream. Steroid ointments may be replaced by various pastes or aqueous shake mixtures to which are added 1-2 per cent of anaesthesin and naphthalan which intensify the antipruritic effect.

With the gradual abatement and elimination of acute inflammation, stronger keratoplastic agents are applied: ointments containing 5-10-20 per cent naphthalan, 1-2 per cent tar which resolve the infiltrate, 2-5 per cent sulphur, 2-3-5 per cent ichthammol, etc.

In treating seborrhoeic eczema of the scalp, oil compresses are prescribed first (to remove the crusts), after which a good effect is produced by Lokasalen, Diprosalic, Hyoxisone, 5 per cent sulphuric, 2 per cent salicylic acid ointments.

Aniline dyes and Castellani's paint produce a good result in microbial eczema.

Prognosis. In acute eczema the prognosis is more favourable. Microbial and seborrhoeic eczemas may be completely cured. Idiopathic, sycosiform and pruriginous eczemas respond to treatment less readily. Recurrences may occur in any form of eczema. The prognosis is much poorer if eczema develops in oedematous and asthenic infants, in elderly individuals, and in persons weakened by infection or toxicosis.

Prevention. Observance of hygienic habits is important in all forms of eczema. Moreover, this contributes to the prevention of secondary infection, which aggravates the course of the main process. Small lesions in mild folliculitis should be painted with Castellani's paint or 1-2 per cent aqueous or alcohol solutions of aniline dyes. In extensive skin lesions the patient is not permitted to take baths or showers for some time. In some patients, however, baths with a chamomile decoction, for instance, and in treating children, a decoction of bran, oak bark, etc. produce a therapeutic effect. Overheating of the body must be avoided.

Patients with eczema are recommended a diet of dairy and vegetable foods, boiled meat, cereals, carrot and apple juices, stewed prunes, vegetables, fruits. Citrus fruits may induce violet exacerbation in some patients. Liquids and easily assimilated carbohydrates should be limited and extractive substances avoided. Alcoholic beverages, salty and spicy foods, canned food and pickles are prohibited. Children must neither be overfed nor undernourished.

Much importance is attached to normal activity of the gastrointestinal tract and treatment of intercurrent diseases.

In patients with the varicose complex of symptoms, elastic stockings or bandaging the legs with therapeutic rubber bandages is a measure for the prevention of varicose eczema. To prevent such eczema, varicosity, ulcers, fissures, fistulas and wounds are treated (jointly with a surgeon). Improper treatment of a burn or frostbite may also lead to the development of eczema.

Nursing mothers with eczema of the nipples must strain their milk. Individuals with eczema of the hands should avoid using water that is either too hot or too cold, and should not use detergents in laundering. Contact with presumable allergens in everyday activities and during work should be excluded as much and as long as possible.

Treatment of infestation with helminths and treatment of foci of chronic or acute infection in the future mothers and a rational diet are very important in the prevention of eczema in infants, because the allergens circulating in the mother's blood-stream penetrate the placenta and sensitize the infant while it is still in the period of intrauterine development. In such cases exogenic allergens entering with the mother's milk after the birth of the child thrive on prepared ground. Pregnant women, particularly those known to have had allergic parentage, should abstain from eating a lot of eggs and sweets and drinking much milk. Their diet should be rich in vitamins and must include a variety of vegetables, boiled meat, yoghourt and cottage cheese, as well as fruits (oranges, tangerines, apricots, peaches, strawberries, raspberries should be limited). It is expedient to prescribe some vitamins in addition to the diet (vitamin A concentrate in drops, the vitamin B complex in pills, ascorutin in tablets).

It is not advisable for patients suffering from eczema to wear synthetic, flannel or woolen underwear. These patients should be kept under dispensary surveillance and examined by the dermatologist regularly for control and prescription of treatment in conformity with the condition of the skin and the body as a whole.

Materials for self-checking:

А. Tasks for self-checking: