The cutaneous deposits are composed of the same histological products imbedded in the dermis or in the subcutaneous connective tissue, and extending in some cases deeply between the muscles, with no clear line of demarcation from the sound tissue. Not only the chains of nodules (farcy-buds), but the connecting lymphatic trunks, are the seat of the characteristic cellular product, and in chronic cases there is the enlargement of the adjacent lymphatic glands as well. In these there is a special tendency to early disintegration and ulceration.
In the diffuse glanderous swellings (infiltrated glanders, inflammatory glanders) the affected tissues are the seat of an inflammatory process with profuse exudation throughout, while in the interstices of the connective tissue are numerous granular glander-cells. The same tendency to necrobiosis is shown as in the other forms of glanderous neoplasms, and such diffuse swellings become the seats of very extensive, deep, and irregular ulcers, or frequently of fibroid growth and induration, forming the so-called cicatricial deposits. These are hard, firm, and resistant, and histologically consist of a dense fibrous stroma interspersed with the spindle-shaped cells. They are especially common in chronic cases, and such an appearance on the nasal mucous membrane is always suspicious, as this dense fibroid appearance rarely follows a simple traumatic lesion.
Diffuse glanderous infiltrations in the nose may implicate the entire mucosa of one or both nasal chambers, and the ulcers are liable to be greater than from the nodular form of the disease. They are also especially associated with thrombosis of the veins, which occurs to a less extent in the nodular form and conduces to the dark-blue tint of the mucosa.
Glanderous infiltration of the lungs is inflammatory in its nature (pneumonia malleosa), attacking an area of two or three inches in diameter at or near the margin of the lungs, and proceeds to caseous necrobiosis, suppuration, calcification, or fibroid induration. In the skin such infiltrations also frequently terminate in induration, while ulceration and abscess tend to appear when the proliferation of glander-cells is most abundant (farcy-buds).
The glander-nodules are not uncommon in muscles, intermuscular connective tissue, spleen, liver, kidneys, and testicles. Leukæmia is also a constant feature, the irritation of the lymphatic glands manifestly stimulating the production of the lymph-cells.
DIAGNOSIS.—The diagnosis of glanders usually rests on the viscid nature of the discharge, the painless nodular swelling of the submaxillary glands and the indisposition to suppurate, the characteristic appearance of the nodules, elevations, ulcers, and indurations of the nasal mucosa, and the presence of the specific bacillus. The diagnosis of farcy rests mainly on the nature of the nodules and corded lymphatics, of the ulcers and their discharges, on the extension of the affection toward the trunk, and the tendency to implicate the respiratory organs. Usually, there are several victims, the earlier ones chronic cases, the later ones acute, or there is a history or presumption of exposure. Yet in many cases, and especially in the more chronic internal forms (laryngeal, pulmonary, etc.), the diagnosis is difficult, and inoculation of a horse, goat, sheep, or rabbit may be the only available means of reaching a decision. Auto-inoculations are unreliable, as parts not yet the seat of active disease will often resist inoculation.
PROGNOSIS.—This is always unfavorable. The constancy of internal deposits and the viability of the germ in such products render it impossible to eliminate the poison from the system in the great majority of cases. In external glanders only is there any reasonably good hope, and even this is confined to the chronic cases. In stating this much, it is not denied that recoveries even of chronic nasal glanders do occur, yet these are few, and the majority of those that do apparently recover usually succumb as soon as they are subjected to hard work or specially trying conditions of life, so that but little faith can be placed in most of the alleged recoveries.
TREATMENT.—Considering the great danger of multiplying and preserving the germs of a disease so fatal alike to man and beast, the treatment of glanders is never commendable. The danger is least in the case of chronic farcy, not only because the processes are less active, but because the virus is not being thrown out and diffused with the tidal air of respiration, sneezing, and coughing. The unbroken farcy-buds and swollen lymphatics may be actively treated by compound iodine ointment, and the ulcerous nodules freely cauterized with corrosive sublimate, biniodide of mercury, chloride of zinc, sulphate of copper, or iodized phenol. Local inflammations may demand fomentations and astringent antiseptic lotions. Meanwhile, the system must be supported by a tonic regimen and medication, abundance of pure air, a liberal and wholesome diet, and the maintenance of the various bodily functions in a healthy condition. Of medicinal agents the most pronounced tonics have the best reputation—sulphate of copper and iron, biniodide of copper, arsenic, and, above all, arsenite of strychnia. Next to these the sulphites rank, and a combination of the two last named is perhaps to be preferred.
PREVENTION.—The glandered horses and all animals attacked with acute or obstinate farcy should be destroyed and their bodies be burned or deeply buried. Every State should legally interdict the use of a glandered horse or his exposure in any public or other place where infection is likely to reach other animals by contact or through fodder, litter, stable utensils, or any other objects employed about animals. No less imperative should be the perfect disinfection of all stables, harness, and other objects with which glandered animals have come in contact. The value of such measures is sufficiently attested by what has been stated above as to the prevalence of this disease in the French army so long as the doctrines of non-contagion dominated in its management, and the comparative disappearance of the disease so soon as a change of theory and method had been inaugurated; the absence of the disease in the English army, where the doctrine of contagion and its extinction has long prevailed; and the entire absence of the disease from Australia, New Zealand, etc., into which it has never been imported, though prevailing in a corresponding latitude and climate at the Cape of Good Hope.