Tuberculosis of the Mouth and Throat. Tubercles sometimes form in the tongue causing nodular swelling, with a caseated centre. Much more frequently they attack the pharynx or larynx with the formation of nodular necrotic swellings, followed by ulcers and the implication of the adjacent lymph glands. The glands are liable to be invaded through the tonsillar and other follicles of the faucial and pharyngeal regions, which like the solitary and agminated glands of the intestines form excellent culture vessels. The glands most frequently attacked are the retro-pharyngeal, but the lateral pharyngeal, the intra-parotidean and submaxillary lymph glands occasionally suffer. They often become indurated, yet the formation of abscess-like sacs is not uncommon especially in the retro-pharyngeal.
Gastro-Intestinal, Peritoneal and Mesenteric Tubercles. Tubercles of the interior of the stomachs are rare, though they are frequent on the peritoneal surface of the first three stomachs, as rounded, subserous nodules varying in size from a pea upward. The mucosa of the small and large intestines may suffer, by preference in the seats of the solitary or agminated glands, and the resulting ulcers may extend in the lines of the lymph vessels from the convex to the attached border of the gut. The small greenish caseated and calcified nodules on the intestines, which are so often mistaken for tubercles, are the degenerated cysts of the œsophagastoma. Tuberculosis of the mesenteric lymph glands is much more common, the successive stages being essentially like that seen in the bronchial glands. Beside these the surface of the mesentery, omentum and abdominal parietes often becomes the seat of congestion, exudation and cauliflower-like neoplasms or grapes, as already stated of the pleuræ. In a certain number caseation or cretefaction may be detected.
Liver Tuberculosis. The liver is greatly exposed to tuberculosis as the single destination of all the blood from the gastro-intestinal tract. Tubercles also form on its surface by direct infection from the peritoneum. The hepatic tubercles are often very large and numerous, adding greatly to the bulk and weight of the viscus. There is usually coincident tuberculosis of the lymph glands of the porta.
Tubercle of the Spleen. This is also a favorite seat of the morbid process, exposed as it is to the reflux of infected blood in the portal vein, and to access of the bacillus from the peritoneum and omental lymphatics.
The pancreas is less exposed to the channels of the circulation and is less frequently affected.
Genito-Urinary Tubercles. The kidneys are always liable to suffer in generalized tuberculosis, in accordance with their function of elimination and the great quantity of blood that passes through them. The tubercles may be numerous, encroaching upon and destroying the glandular tissue, and determining congestion, nephritis and hæmorrhage (Schütz). The ovaries, when tuberculous, lead to nymphomania and sterility; they become swollen, with rounded projections, indurated, and on section show all stages of infiltration, caseation and calcification. They may encrease to a great size. Tubercles are found on the Fallopian tubes, the serous and mucous surfaces of the womb, and in the broad ligaments, in all their characteristic forms. The bladder and vagina are less frequently involved. In the male the testicle, epididymus, tunica vaginalis and prostate vesicles are sometimes affected. The swelling and induration of the affected organ, or the existence of hydrocele, may be noted.
Tubercle of the Udder. From the mass of blood passed through the udder it is specially exposed to infection whenever the bacilli enter the circulation. It may also be directly infected by the entrance through the teat, or a trauma, of the bacillus of the stable dust. There may be for a time only a slight general swelling which leads to no suspicion on the part of the milker, and as the secretion is not arrested, a dangerous product may be distributed. At this stage the lobules on section appear swollen, gray, with paler or yellowish points and minute hæmorrhages. The milk ducts contain coagula and bacilli (Bang). In other cases, usually more advanced, the gland is hard, nodular, enlarged, and shows a marked thickening of the walls of the smaller milk ducts and secreting follicles, with yellowish and even caseous and calcified centres. The gland is often greatly enlarged, the milk suppressed or completely altered, and tubercular neoplasms or ulcers exist in the larger ducts.
Tuberculosis of the Brain and Spinal Cord. As noted in Volume III. this occurs in young cattle especially in the form of tubercles of all ages attached to the pia or arachnoid, on the brain, or cerebellum, or in the ventricles, also in the cerebral matter, in or on the lumbar enlargement of the cord or on its pia. Several cases have come under my notice in the mature cow.
Tuberculosis of the Eye. This has been seen mainly as a result of experimental inoculation, yet casual cases also occur in the cornea, sclerotic, iris or choroid, the product undergoing early necrosis and softening into a yellow mass filling the different chambers.
Tuberculosis of the Bones. Though less frequent than that of internal organs this is not rare. It usually attacks the spongy tissue, near the articular extremities, or the vascular line between epiphysis and diaphysis, giving rise to considerable exudate, thickening of the bone and arthritis. The vertebræ, ribs, sternum, petrous temporal, frontal and occipital also suffer. Sections of the bone show dilatations of the cancelli, filled with the characteristic nonvascular groups of giant, epithelioid and lymphoid cells with, at times, softened and caseated centres. The adjacent bone is congested and softened, so that the detachment of epiphysis and apophyses is not uncommon. In case of invasion of the joints the cartilages and ligaments are the seat of tubercular deposits, softening, fibroid change and caseation, and there is general synovitis. The cartilages of the ear (concha) and nose (septum) may also be invaded.