When the actinomyces are grown upon artificial media their virulence is retained for a considerable length of time. If introduced into the abdominal cavities of rabbits, there are produced in the peritoneum, mesentery, and omentum typical nodules containing the actinomyces

rays.

The organism can also be grown in raw eggs, into which it is carefully introduced through a small opening made under aseptic precautions. In the egg the organism forms peculiar long mycelial threads quite unlike the short forms developing upon agar-agar.

The characteristic rosettes which are constantly found in the tissues are never seen in artificial cultures.

The exact manner by which the organism enters the body is unknown. In some cases it may be by direct inoculation with pus, but there is reason to believe that the organism occurs in nature as a saprophyte, or as an epiphyte upon the hulls of certain grains, especially barley. Woodhead records a case where a primary mediastinal actinomycosis in the human subject was supposed to be traced to perforation of the posterior pharyngeal wall by a barley spikelet swallowed by the patient.

CHAPTER VI.

MYCETOMA, OR MADURA-FOOT.

A CURIOUS disease of not infrequent occurrence in the Indian province of Scinde is one known as mycetoma, Madura-foot, or pied de Madura. It almost invariably affects natives of the agriculturist class, and in most cases begins in or is referred by the patient to the prick of a thorn. It generally affects the foot, more rarely the hand, and in one instance was seen by Boyce in the shoulder and hip. It is more common in men than in women, individuals between twenty and forty years of age suffering most frequently, but persons of any age or sex may suffer from the disease. It is insidious in its onset, as has been said, generally following a slight injury, such as the prick of a thorn. No symptoms are observed in what might be called an incubation stage of a couple of weeks' duration, but after this time elapses a nodular growth gradually forms, attaining in the course of time the size of a marble. Its deep attachments are indistinct and diffuse. The skin becomes purplish, thickened, indurated, and adherent. The points most frequently invaded at the onset are the ball of the great toe and the pads under the bases of the fingers and toes.

In the course of months, although progressing slowly, the lesions attain very perceptible size, distinct tumors being present. Later, sometimes not until after a year or two, the nodes begin to soften, break down, discharge their purulent contents, and originate ulcers and communicating sinuses. The discharge at this stage is a thin sero-pus, and is always mixed with a number of fine round black or pink bodies, described, when black, as resembling gunpowder; when pink, as resembling

fish-roe.

It is the detection of these particles upon which the diagnosis rests, and upon which the division of the disease into the melanoid and pale varieties depends.

The progress of the disease causes an enormous size and a peculiar deformity of the affected foot or hand. The malady is generally painless.

The micro-organismal nature of the disease was early suspected. In spite of the confusion caused by some who confounded the disease with and described it as "Guinea-worm," Carter held that it was due to some indigenous fungus as early as 1874. Boyce and Surveyor believe that the black particles of the melanoid variety represent a curious metamorphosis of a large branching septate fungus, and that the white particles of the other variety are the remains of a lowly-organized fungus and of caseous particles.

Kanthack tried to prove the identity of the fungus with the well-known actinomyces, but there seems to be considerable doubt about the correctness of his view.

Vincent succeeded in isolating the micro-organism by puncturing one of the nodes with a sterile pipette, and has cultivated it upon artificial media. Acid vegetable infusions seem suitable to its growth. It develops scantily in bouillon at the room-temperature, better at 37° C.-in from four to five days. In twenty to thirty days the colony attains the size of a little pea.

In the liquid media the colonies which cling to the glass, and thus remain near the surface of the medium, develop a rose- or bright-red color.

Cultures in gelatin are not very abundant, are colorless, and are unaccompanied by liquefaction.

Upon the surface of agar-agar strikingly beautiful rounded, glazed colonies are formed. They are at first colorless, but later become rose-colored or bright red. The majority of the clusters remain isolated, some of them attaining the size of a small pea. They are generally umbilicated like a variola pustule, and present a curious

appearance when the central part is pale and the periphery red. As the colony ages the red color is lost and it becomes dull white. The colonies are very adherent to the surface of the medium, and are said to be of cartilaginous consistence. The organism also grows in milk without coagulation.

Upon potato the development is meagre, 'slow, and with very little tendency to chromogenesis. The colorproduction is more marked if the potato be acid in reac

FIG. 62.-Streptothrix Maduræ in a section of diseased tissue (Vincent).

tion. Some of the colonies upon agar-agar and potato have a powdery surface, no doubt from the occurrence of spores. It is, of course, an aërobic organism.

Under the microscope the organism is found by Vincent to be a streptothrix-a true branched fungus consisting of long bacillary branching threads in a tangled In many of the threads spores could be made out.

mass.

Vincent was unable to communicate the disease to animals by inoculation.

Microscopic study of the diseased tissues in cases of mycetoma is not without interest. The healthy tissue is said to be sharply separated from the diseased masses. The latter appear as large degenerated tubercles, except that they are extremely vascular. The mycelial or filamentous fungous mass occupies the centre of the degeneration, where its long filaments can be beautifully demonstrated by the use of appropriate stains, Gram's method being excellent for the purpose. The tissue surrounding the disease-nodes is infiltrated with small round cells. The youngest nodules are seen to consist of granulation-tissue, which in its organization is checked by the coagulation-necrosis which is sure to overtake it. cells are few.

Giant

Not infrequently small hemorrhages occur from the ulcers and sinuses of the diseased tissues; the hemorrhages can be explained from the abundance of small blood-vessels in the diseased tissue.

Although the disease has been described as occurring in Scinde, it is not limited to that province, having been met with in Madura, Hissar, Bicanir, Dehli, Bombay, Baratpur, Morocco, Algeria, one case by Bastini and Campana in Italy, and one by Kempner in America.