Skin Diseases of Children/Contagious Impetigo

by George Henry Fox

Plate III

Impetigo Contagiosa

From the collection of photographs of

Dr. George Henry Fox

CONTAGIOUS IMPETIGO.

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The affection known as contagious impetigo, though a very common one, is by no means as clearly defined as other dermatoses of frequent occurrence. Crusted lesions or scabs resulting from the use of the finger nails and the drying of a copious blood-stained secretion are frequently seen upon the faces of children, but the origin and nature of this eruption are hot always plain. That the lesions are contagious and auto-inoculable is a matter of simple observation, and that pus cocci play an important part in their development is generally admitted. Mothers and nurses are often affected by children under their care.

It is undoubtedly the presence of micro-organisms which occasions the crusted or impetiginous form of eczema (the crusta lactea, or milk crust of infants). In these cases we have an ordinary eczematous inflammation of the skin due to some internal condition, but the peculiar clinical aspect of the eruption—viz., the suppuration and crusting—is without doubt due to the external agency of pyogenic microbes. In other cases minute aggregated pustules develop superficially and exude an abundant honey-like secretion which dries into yellow, gummy crusts of varying size and irregular outline. This eruption is comparatively rare, affects adults as well as children, and is by some regarded as a pustular eczema and by others as impetigo or contagious impetigo. In fact it is difficult to determine in practice precisely what cases should be included under the last-named affection, but a large number of cases occurring in children present certain definite lesions which are readily recognized and indicate an identity of origin.

In a typical case of contagious impetigo (and it is questionable whether there is any impetigo which is not contagious) the lesion is usually a flattened vesico-pustule. This is small at the outset, superficial, and without any surrounding area of inflammation. It is always single, although when the pustules are very numerous, a number of them in close proximity may appear like an irregular group. When this lesion escapes being scratched, and thereby altered in appearance, it tends to increase peripherally and to become depressed in the centre. It usually reaches its maximum development in a few days, and is about the size of a five-cent nickel. At the advancing border the epidermis is raised by a milky, purulent secretion while the depressed centre appears of a darker hue. Upon the back of the fingers or hand, where, next to the face and scalp,

Fig. 10.–Contagious impetigo.

the lesions are most common, they look like recent and accidental burns. Upon the palm, where the thicker epidermis is less likely to be ruptured, the lesions are apt to present the appearance of hemispherical or flattened pustules, quite similar to, though somewhat larger than, the pustules occasionally observed in scabies. After an existence of about a week the contents of the pustules tend to dry into yellowish, honey-like or "straw-colored" crusts. If the lesions remain uninjured by the finger nails, the affected skin gradually heals and the crusts appear as though "stuck on" to the cutaneous surface. When thoroughly dried these crusts fall, and even when picked or rubbed off they leave no ulcerated surface, but merely a small hyperæmic area.

It is only in exceptional cases, however, that this natural and characteristic evolution of the lesion can be observed, for in children, especially, the irritation of the lesions usually provokes scratching, which changes their clinical appearance, and a little blood mingled with the purulent secretion gives rise to

Fig. 11—Confluent lesions of impetigo.

the formation of a dark crust or scab. Upon the extremities, especially the legs, friction of the clothing, dirt, and constant scratching frequently inflame the lesion, and a dark crust upon a superficial ulceration with a narrow red areola is produced, which has generally been described as a distinct skin affection under the name of ecthyma. These ecthymatous pustules, common in cachectic children, are often associated with the characteristic lesions of contagious impetigo upon the face and hands and are evidently of similar if not identical origin.

In certain cases of vaccination a double infection may sometimes take place. When the vaccine virus has produced a vesicle, the microbes of contagious impetigo may be accidentally implanted. The vaccine lesion now becomes unusually inflamed and itchy. Through scratching a number of other crusted lesions are developed upon the arm and elsewhere, and doubtless some of the cases of generalized vaccinia which have been reported may be justly considered to have been cases of contagious impetigo beginning at the point of vaccination.

Fig. 12.—Umbilicated lesion on forehead.

Upon the scalp the lesions of contagious impetigo are frequently found, and usually appear as small, isolated, circular crusts. These frequently occasion temporary areas of partial baldness, and when the disease is of long standing and there is very much suppuration a permanent loss of some hair may result. The affection is often associated with pediculosis capitis, and in such a case the frequent scratching of the head is very apt to multiply the lesions, and often the diagnosis is obscured by the development of eczema upon the scalp and back of the neck. In impetigo of the head and face the cervical and submaxillary glands are very apt to become enlarged and tender, and in strumous, ill-nourished, and neglected children glandular suppuration may occur. Among this class the affection frequently coexists with paronychia and ulcers of the conjunctiva and buccal mucous membrane. It is said to occur with especial frequence in female children and in the spring, although neither sex nor season is exempt.

The upper illustration in the accompanying plate shows crusted lesions upon the forehead and scalp, and a secondary conjunctivitis which has closed the right eye. Upon the hand a number of incipient pustules are seen, excoriated upon the fingers, but tolerably well developed upon the wrist. Upon the forearm, in the lower illustration, a few typical flattened and umbilicated lesions may be seen, while upon the arm an ecthymatous patch has resulted from the coalescence of several scratched and crusted lesions. In Fig. 10 the eruption presents its characteristic appearance in the form of numerous isolated crusted lesions. In Fig. 11a few lesions have coalesced upon the lips and formed a large, crusted patch resembling impetiginous eczema. In Fig. 12 the lower lip is similarly affected, while upon the forehead the isolated lesions present a typical appearance.

While the individual lesions of contagious impetigo run an acute course of a week or ten days, the development of new lesions and the irritation produced by scratching often keep up the eruption for many weeks. In its treatment cleanliness is of the utmost importance, especially as the affection is most likely to occur among children whose ablutions are neither frequent nor thorough. The finger nails may be advantageously cleansed and cut, and a disinfectant lotion, such as listerine or a saturated solution of sodium hyposulphite in rosewater, should be applied frequently to the affected skin. To remove crusts and heal superficial ulceration an excellent application is a mixture of equal parts of white precipitate ointment and cold cream.