Acute Myositis.

Synonym.—Acute Polymyositis.

Definition.—An acute or subacute inflammation of the voluntary muscles, and generally recognized as being due to microorganisms or toxins produced by them.

Etiology.—This is a disease of adult life, and occurs more frequently in males than females. It is believed to arise from a micro-organism or to the influence of toxins, though no specific germ has as yet been found. It has occurred in the course of broncho-pneumonia, tuberculosis, and diabetes.

Pathology.—While all the voluntary muscles may be involved, the ocular and masseter usually escape. The muscular fibers are chiefly involved, though the interstitial may not escape. With the hyperemia, there is marked exudation of the leukocytes, the tissues become swollen, and, as fatty degeneration takes place, they assume a yellowish-white color. Hyaline degeneration sometimes occurs, and hemorrhage may be observed. The muscles are usually quite friable.

Symptoms.—The disease comes on gradually, the muscles of the extremities being the first to be involved, followed in turn by those of the trunk. The muscles become swollen, stiff, and painful, interfering with locomotion, and are tender when palpated, and slight edema, is sometimes present. As the disease progresses, general edema may take place, while an erythematous eruption may appear, attended by more or less pigmentation.

There is general systemic disturbance, as shown by headache, nausea, and vomiting, fever of moderate intensity, and enlargement of the spleen. As a result of the impaired action of the muscles, respiration and deglutition may be greatly impaired. Bronchitis, broncho-pneumonia, tuberculosis, and diabetes may develop during the course of the disease.

Diagnosis.—The clinical symptoms of trichiniasis are so nearly identical that a microscopical examination of the diseased muscle will be necessary to distinguish the one from the other.

Prognosis.—The disease generally terminates fatally in from one to three months in the acute form, or from one to three years in the chronic form.

Treatment.—The treatment will be symptomatic. Where sepsis is prominent, the well-known antiseptics, echinacea, baptisia, the chlorates, sulphites, and mineral acids, will be used.

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