(Miliary tuberculosis of the skin; Ulcer of the phthisical; Tuberculosis ulcerosa)
The rare forms considered under this head were once supposed to be the only cutaneous manifestations of tuberculosis. The typical lesion is commonly single and may be described as an indolent, rounded, shallow, discrete, reddish-yellow, granulated ulcer, with a typical gnawed-out look due to degeneration of miliary tubercles at the edges. If this ulcer is painful and sensitive, it is due to the friction, tension, and irritating secretions owing to its peculiar location at the mucous outlets (nose, mouth, anus and vulva). Miliary tubercles are often noted in the adjoining mucous tracts. There is no doubt that these orificial ulcers are very rare. Chiari’s examination of about 4,000 tuberculous bodies demonstrated only five of these ulcers and these were all the lower lip. This has been verified by the experience of Henry M. Dearborn and myself which covers the records of some 5,000 cases of pulmonary tuberculosis in which only six ulcers were found.
Etiology and Pathology. – These ulcers are no doubt due to an autoinoculation of some slight abrasion or simple inflamed lesion at, or near, the margin of the mucocutaneous orifices in those suffering from internal tuberculosis. Rarely these lesions may be said to be the result of an actual distribution of the tubercular process. Microscopically the findings are similar to miliary tuberculosis of the lungs, showing miliary nodules, caseation, softening and ulceration. In these lesions the tubercle bacilli are comparatively abundant.
Diagnosis should be readily made when pulmonary and other internal forms of the disease can be demonstrated. Evidences of the disease may also be found on the adjacent mucous membranes. Though it is wise to look for tubercle bacilli, failure to find the organisms is no proof that the disease is absent.
Prognosis. – As regards the healing of the ulcers, prognosis is good and it is needless to mention the probable outcome of the associated general tuberculosis.