Nummular Eczema

Filed under: 3.3 - Nummular Eczema

Some dermatologists classify nummular eczema as infectious eczematoid dermatitis, some group it by itself. For the present, I prefer to group it by itself.

Nummular eczema is not uncommon in children after the first year; I have rarely seen it before this. It appears as circular coin-sized (nummular) patches on the extremities, trunk, and face. These patches may be few or many, and it is common for several to co­alesce and to form sheetlike areas, especially on the lower legs. The skin between the patches is normal in appearance. I have never seen erythroderma in nummular eczema. Each patch is made up of many small vesicles, which rupture easily, ooze a little, and crust. The larger areas especially are considerably thickened and “boggy,” and of a deep purplish-red color. Itching is variable : some­times very little, sometimes a lot. In addition to the nummular patches there is in many patients* what appears to be ordinary atopic derma­titis on the face, neck, and sometimes on the legs. Nummular eczema may occur in children with strongly posi­tive skin tests, especially to egg white, or in children with entirely negative skin tests in whom 110 allergy can be demonstrated. Like some of the “fixed” drug eruptions it tends to recur in exactly the same places where it was in the beginning.

The cause is unknown, although there is some evidence to indicate

“I   am   talking   about   babies   and   children only.

that a partial cause may in some cases be a low-grade infection with staphylococcus plus sensitization to the infecting organism. This view is held by Fowle and Rice.⁰ By an in­genious method of plate culture simi­lar to that employed by Storck, they demonstrated clearly that plaques of nummular eczema contained an enor­mously greater number of staphylo-cocci than on the normal skin, and they reported good results with staphylococcus toxoid and vaccine. It is clinically true that flare-ups are often seen in children who have num­mular eczema, when they develop a nasopharyngeal infection or a tonsil­litis, and that some can be cured by removal of tonsils and adenoids. Such foci of infection are found by no means in all of these patients, how­ever.

Fig. 15.-Nummular eczema.

Children with nummular eczema can be helped a great deal by proper treatment, but recurrences are com­mon. I have never seen the removal of any food or environmental allergen do any good. It is probably best, how­ever, if there are positive skin tests to foods, such as egg white, to with­hold the corresponding foods from the diet. This will have no effect upon the “nummular” lesions, but it may help the ordinary eczema which so commonly goes along with them. Furthermore, some of these children are so sensitive to egg white that they can eat none of it without severe and immediate symptoms such as vomiting, urticaria, or even shock- entirely apart from what the eating of egg might or might not do to the eczema. If there is a focus of infection in the nose or throat (puru­lent nasal discharge or infected ton­sils), the use of an antibiotic will probably get rid of it, and when this happens, the eczema is likely to be greatly improved.

I have seen one prompt and spectacular cure of a nummular eczema by the use of peni­cillin nose drops and penicillin in­ternally for a boy who had a profuse purulent nasal discharge. If no focus of infection can be found I doubt that antibiotics do any good. Antibacterial treatment of the lesions accomplishes but little; one would expect that if they were actually caused by bacteria, treatment with ammoniated mercury or antibiotic ointments would cure them: it does not. Vioform some­times does fairly well; whether due to its antiseptic action or something else I do not know, but in my experience the  only local  treatment  that  really amounts to much is the use of crude tar, full strength, painted on each lesion twice a day. It is allowed to dry a little, then powdered with talc.

Fig. 16.-Nummular eczema. Local treatment: smaller lesions to be painted with un­diluted crude coal tar. Larger lesions to be treated with a strong” tar paste. No greasy, thin ointments to be used. (From Brennemann’s Practice of Pediatrics.)

If there are large patches it is best not to paint them all at once, but to get rid of a few at a time and then go on to the others. Results with this treatment are sometimes spectacular, and I have seen in some cases complete disappearance of the smaller patches in a few days. The large, purplish, boggy plaques on the legs are more difficult,   and  progress  is   slow.

Fig 17 Nummular eczema

Fig 18 Nummular eczema

For such places a thick tar paste does well (see atopic dermatitis). Greasy ointments should not be used. The ordi­nary eczema which may be present around the neck and on the face is helped by hydrocortisone ointment if not much thickened; if thickened, tar paste is better. (See Fig. 17.) This child was treated with hydrocortisone ointment to the face and neck, crude coal tar to the small places on the body, and tar paste to the legs plus bandages.

I cannot emphasize too strongly the superiority of coal tar for nummular eczema over anything else that I have used; treatment must be persistent, however. I have treated several patients who had nummular eczema with cortisone by mouth, and have come to the conclusion that it is no good. In ordinary dosage (75 mg. per day) it accom­plishes very little, and I do not recom­mend the use of larger doses for chil­dren with eczema. The boy in Fig. 18 was treated with oral cortisone, 50 to 75 mg. doses for a long time without much effect, except to dimin­ish the oozing. Once when he was in a hospital the resident gave him 150 mg. for a day or two. The eczema improved, but he developed severe potassium deficiency, and nearly died from it. I do not like large doses of cortisone for babies with eczema.

⁶Fowle, L. P., and Rice, J. W.: Etiology of Nummnlar Eczema, Arch. Dermat. & Syph. 68: 69, 1953.

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