—Owing to the greater delicacy of the mucous membranes they are more frequently the site of primary lesions than the skin: 85 to 90 per cent. of all primary sores occur about the genitalia; in men, especially on the inner side of the prepuce, the glands, and the sulcus behind it; externally, chancre may occur upon any part of the surrounding skin; in women, the tissues about the vulva are most frequently its seat. Occasionally it is found within the vagina, but rarely upon the os. The so-called extragenital chancres are met with anywhere, especially on the most exposed parts, as the lips, tongue, tonsils, eyelids, and nipples. Syphilis is occasionally conveyed to a wet-nurse by the infected mouth of an infant suffering from hereditary disease; even multiple chancres sometimes occurring. Conversely, children have been infected by wet-nurses with syphilitic lesions about the nipple. The disease has been conveyed by bites, as upon the face and fingers. Surgeons and obstetricians are peculiarly exposed, as are also nurses, to this disease, especially occurring upon the fingers and hands. Infants have been known to be inoculated during parturition. These are all examples of direct or immediate contagion. On the other hand, the disease may be positively conveyed by utensils in common use between different individuals, as table-ware or tobacco-pipes; by tools of trade which are passed from one person to another, as, for instance, the blowpipe in glass factories; and by cigars as they are made in some places, the wrapper being moistened from the mouth of the cigarmaker. These are examples of its indirect transmission. Physicians are familiar as well with instances where the disease has been conveyed by instruments, either surgical or those of the dentist. So possible is this last form of contagion that dentists are trained to sterilize their instruments as carefully as does the surgeon.
Possibility of conveying syphilis by vaccinal lymph has been alluded to as occurring only in those instances where the blood of the syphilitic patient is mingled with the lymph. The production of vaccinal virus is now, however, so well regulated that it is rare that the surgeon employs humanized lymph. Some cases considered vaccinal have been due to the use of infected instruments; hence the necessity for extreme caution in this regard. When the disease is acquired in a non-venereal manner it is called syphilis insontium, or syphilis of the innocent; this, however, is an unfortunate expression, as it tends to cast reflections upon other cases which may be, in effect, just as innocent.
Symptoms of the Ulcer.
—In all probability the initial sore and the ensuing lymphatic involvement are due to the parasite and to its toxic products. These latter are quickly taken into the general circulation and are held to confer the immunity which syphilitics enjoy before the outbreak of the general eruption. Anemia, malaise, and other like symptoms are evidences of a progressive intoxication or toxemia, while the earlier eruptions, which tend to evince the contagious element in a rather virulent form, may be due to the germs alone, or combined with their toxins. On this hypothesis can be explained the partial or complete immunity evinced by mothers who bear syphilitic children, the infection coming from the father.
From the first evidence of infection the whole syphilitic process gives evidence of its infectious character. The bloodvessel walls undergo a thickening of their coats and more or less obliteration of their lumen, and this, of course, causes a disturbance in the nutrition of the parts supplied by them. This vascular change can be recognized even in the minute vessels of the initial lesion, and thereafter pertains to most if not all specific manifestations of the disease.
Our knowledge of the nature of this disease would be more complete were it possible to convey it to animals, but these are practically exempt from it, for the few and rare instances where, it is said, the disease has been inoculated upon the higher quadrumana furnish insufficient data. In this respect the disease is like the exanthemas, of whose parasitic origin there can be no question.
The First Period of Incubation and the Chancre.—The time which elapses between the exposure and the first appearance of the initial lesion is known as the first period of incubation. This varies, within wide limits, from ten days to forty or fifty; some writers have made it even seventy days. The average period varies from three to four weeks. There is often uncertainty as to when the induration began, and patients, women especially, may easily make a mistake of several days in fixing this date.
Every case of acquired syphilis begins with an initial sore, though this may be so located or so complicated with some other lesion as to be overlooked. The character of the induration varies somewhat with the location, i. e., whether upon the skin or mucous membrane. The amount of moisture or maceration to which it is exposed will also influence its appearance. It may be minute, so as to almost elude observation even on visible parts, or it may spread and involve an area 1 Cm. in diameter. The lesion is usually solitary, but when several abraded spots are infected at the same time there may be multiple sores. When a surgeon sees a lesion of this character it has usually changed its original appearance—perhaps by some previous treatment, perhaps by maceration. There is one invariable feature upon varying expressions of which diagnosis is based, and that is induration. The instances in which this fails are very rare; on the other hand, it is possible that it may be the result of treatment already undergone, and for this reason the recent history of the case should be obtained; in other words, the typical chancroid is always indurated, but an indurated sore does not of itself necessarily indicate syphilis if it can be satisfactorily accounted for in other ways. The presence of an active primary lesion seems to confer immunity to subsequent infection for a period co-equal with the active manifestations of the disease, although even in this respect exceptions are occasionally to be noted.
The induration of syphilis develops beyond and beneath the limits of the superficial lesion, and gives the sensation, when grasped between the fingers, of a piece of firm material embedded in the skin or membrane. It is firm, slightly elastic, with usually well-defined boundaries, which accounts for the expression, parchment induration. Ordinarily no pain or other sensations accompany its formation or attract attention; hence the frequency with which it escapes observation for some time and the uncertainty which the patient feels regarding the dates. The surface of the induration usually becomes moist or abraded and frequently ulcerated; but these surface lesions tend eventually to heal, even if let alone, except in those parts, e. g., the lips, where they are constantly bathed by discharge.
The characteristic induration disappears slowly in a few weeks or months, leaving ordinarily no trace of its existence, although sometimes a small scar, occasionally pigmented, is left to mark its site.