Symptoms of Chronic Nasal Glanders in Solipeds. The chronic form of the disease follows an indolent course, and local symptoms are often so slight or equivocal that the true nature of the malady is unsuspected. If the patient is well fed and cared for and not overworked, the malady may run a course of three, five or seven years, and the victim may pass through many hands leaving infection in every stable it occupies. Diagnostic symptoms, more or less clear, may be obtained from the discharge; the lesions of the mucosa and the submaxillary glands.
The nasal discharge may be bilateral, but if confined to one nostril is strongly suggestive of glanders. It may be profuse or scanty, continuous or intermittent, of a yellowish, purulent tint, or greenish, or grayish and with a special tendency to viscidity. In some indolent cases the nostrils may be clean but if there is any matting of the long hairs, or adhesion of the alæ nasi, the case is specially suspicious. If it is sanious, flocculent, or bloody it is all the more characteristic, and suggests the supervention of an acute attack.
The lesions of the pituitary membrane are varied. Hyperæmia of a purple or violet color is common, especially along the septum, and the mucosa is liable to be somewhat tumid or œdematous. Nodules the size of a pin’s head, a pea or larger appear inside the inner ala, or on the septum or turbinated bones, and at first red from extravasation and, as it were vesicular, become grayish, whitish or yellow with points of red and surrounded by a deeply congested areola. Larger nodules forming in the submucosa approach the surface and stand out the size of the tip of the finger and with the same general character as the smaller. Sooner or later these degenerate and form ulcers which bear a resemblance to those of acute glanders but are less angry, and when small and solitary may be taken for simple erosions. In other cases they become thickened and indurated with sharply defined projecting margins, and a yellowish base with points or lines of red. The presence of red, black, green, or brown crusts may also be noted.
Another lesion frequently observed in indolent cases is a cicatricial white spot or patch in which the hyperplasia has become partially developed into tissue and shows no tendency to ulcerate. The mucosa may even be drawn or puckered around the cicatrix, making the illusion all the more complete.
The submaxillary swelling is even less sensitive than in acute glanders and produces the same sensation as of an aggregation of small, hard, pea-like, masses with no tendency to ulcerate.
Symptoms of Cutaneous Glanders (Farcy) in Solipeds. Acute cutaneous glanders has been already referred to under nasal glanders. The chronic type is often less characteristic, yet may be detected by careful observation of the symptoms. The main symptom may be the swelling of a joint with more or less engorgement of the limb from attendant lymphangitis. There can usually be detected around the margins of such swellings firm, tender cords representing the larger lymphatic vessels and often branching in their course. In the absence of the engorgement, or when it is slight, these cords may be the main evidence of the disorder, and in the hind limb usually follow the course of the flexor tendons on the inner side of the digit, metacarpus and thigh. At intervals along the line of the cords appear nodular masses (farcy buds) varying in size from a pea to a hen’s egg, and showing a great disposition to soften and discharge a glairy, sanious or more or less bloody liquid. The inner sides of the fetlock and tarsus are favorite seats of these nodules but they may form at any point. On the trunk also the corded lymphatics and nodules follow the lines of the veins and lymphatics, and here there may be the complication of large intermuscular abscesses often in connection with the groups of lymphatic glands.
Latent or occult glanders is often met with, the indolent, specific lesions being confined to some internal organs, like the larynx, lungs or womb, or to the testicles, the nasal diagnostic symptoms being absent. A chronic cough, with a slight purulent discharge from the nose, a chronic leucorrhœa, a swollen testicle, or simply a persistent low condition or weakness without apparent cause, may be the only indications, and special means of diagnosis are demanded.
Special Means of Diagnosis. In occult cases, the disease may be identified by inoculation, or by the mallein test.
Inoculation is best performed on a very susceptible animal. If the suspected discharge from the nose, vagina, open sore or preferably from a freshly incised nodule is inoculated subcutem in the flank of a male Guinea pig, or better in the peritoneum, there develops a local ulcerous sore and on the second or third day a violent orchitis in which pure cultures of the bacillus can be obtained. The caseous and purulent centres are found not only in the testicle but along the line of the spermatic cord, affecting the tunica vaginalis and connective tissue. Death usually follows in four to fifteen days. The cat and dog can also be utilized, inoculation being made on the forehead. Old wornout, but otherwise healthy asses, and even horses make very available subjects, inoculation in the nose speedily developing acute glanders. In the absence of a good subject the suspected animal is sometimes availed of, scarifications being made in the nose and the morbid product rubbed in freely. The rapid development of ulcerous wounds is characteristic. If, however, the case is chronic, and if a fair measure of immunity has been acquired this test may prove misleading.
Test by Mallein. Mallein is the sterilized and concentrated toxic product obtained from a pure culture of bacillus mallei in a peptonized glycerine bouillon. When injected hypodermically in a small physiological dose this has no effect on a sound horse, but in one affected with glanders it develops in several hours an extended swelling in the seat of inoculation, hot, tense and painful, which continues to enlarge for 24 to 36 hours and does not subside for 4 or 5 days. From the margin of the swelling, swollen lymphatics may often be traced running toward the adjacent lymphatic glands. There is also decided dulness, prostration, inappetence, staring coat and tremors. The body temperature rises 1.5° to 2.5° and upward from the eighth hour after inoculation attaining its maximum from the tenth to the eighteenth hour and subsiding slowly to the forty-eighth to the sixtieth.