The causes of lymphangiectasis appear to be generally some obstruction to the onward flow of the lymph. Any diseased condition, therefore, that causes compression of the larger lymph vessels may cause dilatation of the smaller ones leading into these. General distension may come from disease of the lungs or left heart and increased venous blood pressure, or from thrombus of the jugular, or a tumor obstructing the thoracic duct, while local engorgements may come from the pressure of tumors, or the occurrence of lymphangitis and formation of fibrinous coagula. In cases of partial obstruction of the lymph vessels the increased secretion of lymph may lead to distension and enlargement. It may be named in this connection that irritation of the sensory nerves in dogs has been shown to determine a larger production of lymph (Krause). Lymphadenitis and the obstruction of the passage of lymph through the glands is an obvious cause, and hence the disease is specially liable to appear in connection with diseases which show a predilection for the lymphatics (tuberculosis, glanders, strangles, carcinoma, etc.)
In his work on dilatation and occlusion of lymph channels Busey shows that in man the majority of cases are in hospital patients in whom blood and general health have been impoverished and reduced by unhygienic conditions. One case gave support to the theory of maternal impression, the pregnant mother having suffered from over-use of the right limb on a sewing machine, and the offspring having shown extensive lymphangiectasis in the right leg.
Symptoms consist in enlargement of the lymph vessels or plexus, and often of the glands. If of the lymph plexus it may appear like a dropsical effusion in the part, with or without saccular dilatations at intervals. If of the larger vessels, their tortuous anastomosing trunks following largely the lines of the veins are usually characteristic. If the distension is slight it is usually moniliform, as the valves are still intact, and the intervals between them stand out as bladder-like masses. If the structure is wounded or if it ulcerates there is the discharge of a straw-colored fluid, often rendered milky by the presence of fatty granules, and at times tinged with blood. There is always a tendency to the increase and condensation of the connective tissue surrounding the vessels, and fatty degeneration and the formation of lipomata are not uncommon.
Treatment. Compression, by flannel or elastic bandage, from the foot upward, is the simplest and most promising treatment when the limb is affected. The local application of cold, astringents or iodine may be added. Punctures, ligatures, and cauterization have not given encouraging results. Ligature of the nutrient artery of the part, has succeeded in one or two cases, but has failed in others. Tonics are to be tried more particularly in cases due to specific debilitating diseases. Sometimes a spontaneous recovery has been noticed when the surrounding connective tissue has increased and contracted in connection with inflammation.
LYMPHORRHŒA. LYMPHORRHAGIA. DISCHARGE OF LYMPH THROUGH WOUNDS OR SORES.
Result of rupture of lymphatics. Milky, fatty lymph. Treatment, ligature, excision, cauterization, of little avail. Compression. Tonics.
Obstruction of a lymph duct may lead to rupture and the discharge of its fluid on the surface or into an internal cavity. Dr. Cayley records a case of fatal peritonitis in man from rupture of the receptaculum chyli, and the formation of lymph fistulæ has been attributed to filaria sanguinis hominis. We are aware of no corresponding case in connection with the blood parasites of the horse or dog. In the larger domestic animals the great thickness and resistance of the skin offers a barrier to the rupture of subcutaneous lymph vessels, but this no longer applies in case of a suppurating or ulcerous wound. The escaping lymph has often a milky hue from the admixture of fat, just as its escape in the kidneys causes chyluria, and in the bowel fatty stools. The escape is often very profuse and persistent, and results in marked debility. Ligature and excision of the fistulous vessel, also caustics—actual and potential, have been tried with rather poor success. Fitzer succeeded in an obstinate case by the extensive application of nitrate of silver and others by simple compression. As the victims are usually debilitated a course of tonics is usually desirable.
LYMPHADENITIS. INFLAMMATION OF THE LYMPH GLANDS.
Result of lesions of tributary tissues. Arrest in glands of microbes and other irritants. Trauma of gland. Inflammation. Symptoms, swelling, stiffness, gland tender, hot, pitting envelope, corded lymph vessels, abscess, fever. Lesions. Treatment, antiseptics, astringents, emollients, vesicants, lancing, antiseptics, antiphlogistics, antithermics. Chronic adenitis. Symptoms, enlarged glands without engorgement, if simple affects a single gland, if infectious, a group. Lesions, gland swelling, induration, shrinking, follicular distension, pigmentation, growth of lymphocytes, caseation, calcification. Treatment, antiphlogistic, antiseptic, iodine, chloride of calcium, iodide of potassium.
Apart from traumatic lesions lymphadenitis virtually implies some lesion of the tissues from which the different vessels of the glands proceed. The glands however have been referred to as filtering agents on the course of the lymph vessels and in this partial view of their functions we find abundant reason why irritants carried in the lymph stream, should be arrested with pathogenic results in the glands. A particle of pigment gaining entrance to the lymph vessels tends to be arrested among the trabeculæ of the gland, and contributes to the pigmentation so common in old animals. Cells and granules from malignant tumors, and bacteria from an infection-atrium are arrested in the glands and make these the great centres of infection-lesions.