Synonyms.—Big Jaw; Lumpy Jaw.

Definition.—A specific infectious disease of domestic animals, particularly' cattle, communicable to man, and caused by the ray-fungus, the streptothrix actinomyces.

Etiology.—Dr. Bollinger was the first to observe the ray-fungus as a cause of big-jaw, in 1877. The following year, Israel found the same in man, while Ponfick, in 1879, proved their identity. The actinomyces is a fungus, consisting of delicate filaments or threads radiating from a common center; hence the term ray-fungus. These threads present a fine, delicate network, part of which shows a tendency to branch; the ends of the filaments are bulbous or club-shaped.

Infection takes place, as a rule, through the mouth, though rarely, through the respiratory apparatus, and through a cut or abraded surface. The cereals, barley and rye, are supposed to contain the fungus, and may be a source of infection to cattle. As yet there is no evidence that man contracts the disease from the ingestion of diseased milk or meat.

Pathology.—The fungus produces a granulomatous tumor, similar to that produced by the bacillus tuberculosis, and consists of a mass of proliferated connective tissue-cells, among which are seen epithelioid and giant cells. As the growth increases in size, there is a rapid proliferation of the neighboring connective tissue, and the mass takes on the appearance of a sarcoma, and when located in the jaw may be mistaken for osteosarcoma.

While the disease is known by the name of big-jaw, we are to remember it is not limited to any organ; thus we have actinomycosis of the lungs, digestive tract, and skin. Ponfick says: "There are very few portions of the human body which may not be the seat of the actinomycotic process, and almost no organ which may not furnish lodgment for its primary focus."

Symptoms.—Actinomycosis is a chronic disease, and makes its appearance so slowly and insidiously that its early symptoms are overlooked. Again, the fact that it may attack any portion of the body gives rise to a multiplicity of symptoms; it will be well, therefore, to speak of the more prominent forms separately.

First, of the Face.—The first suspicious symptom may be pain in the jaw, or the teeth may seem affected. Again, the patient experiences pain in swallowing, and there is slight stiffness of the jaws. Following these rather vague symptoms, nodular elevations appear on the jaw or the neighboring tissues; these develop slowly, and generally without pain. Finally, after months of progressive changes, involving both hard and soft structures, the tumor mass suppurates, discharging a yellowish pus, in which is found the fungus. When the respiratory apparatus is involved, there is cough, with the development of the pulmonary abscess, and the expectoration of a fetid, disgusting mass. Progressive emaciation takes place, night-sweats occur, and the disease may be taken for phthisis or putrid bronchitis.

Where the disease invades the digestive tract, there is gastro-intestinal disturbance, and when the submucous nodules, which have developed in the mucous membrane of the bowels, suppurate, the ulceration may cause perforation or peritonitis.

Where the disease involves the skin, cutaneous actinomyces, chronic suppurating ulcers discharge a non-offensive pus, yellow in color, greasy to the touch, and containing fine granules, which may be seen by the unaided eye, and which contain the fungus.

Diagnosis.—The positive diagnosis is the presence of the actinomyces in the discharged pus. The hardness of the swollen jaw and neighboring tissues, the long course of the disease, the yellow pus with visible granules, and the characteristic pyemic symptoms, all point to the disease; but the one absolute proof is revealed only by the microscope, the presence of the ray-fungus.

Prognosis.—The prognosis depends largely upon its location. When it appears externally, as upon a bone or upon the skin, and surgical aid is invoked while the disease is yet local, the prognosis will be favorable, but where internal organs, the brain, lungs, liver, intestines, etc., are involved, the prognosis is decidedly unfavorable. The disease usually terminates fatally.

Treatment.—The treatment is principally surgical, the offending parts being removed wherever it is possible. The internal treatment should be antiseptic, supportive, and constructive. Agents which improve nutrition and secretion, which improve the quality of the blood, and at the same time stimulate the excretions, will be found to give the best results.

The Eclectic Practice of Medicine, 1907, was written by Rolla L. Thomas, M. S., M. D.