LYMPHANGIECTASIS. DILATED LYMPHATICS.
Result of lymphangitis, of heart disease, of pulmonary arterial thrombosis, of external jugular plugging. Causes, obstruction to lymph flow, compression, increased venous blood pressure, fibrinous lymph coagula, action of sensory nerves, of lymphadenitis, anæmia. Symptoms like dropsy if in plexus, in large lymphatics, moniliform swelling, sacculation, wounds discharge lymph, hyperplasia of connective tissue, fatty deposits, lipomata. Treatment, elastic bandage, cold, astringents, iodine, punctures, ligatures, cauterizations, tonics.
The most striking cases of dilatation of the lymphatics in the lower animals are met with in horses that have suffered repeatedly and severely from the lymphangitis of plethora. Then the lower part of the shank and the pastern are enormously thickened to perhaps two or even three feet in circumference, and skin and connective tissue are the seat of a general dilatation of the lymphatic plexus and vessels with great thickening of their walls. Nocard and Barrier record cases of general dilatation of the lymphatics in dogs in connection with heart disease, also the case of a horse with old standing thrombosis of the pulmonary arteries, hypertrophy of the right heart, and dilatation of the thoracic duct to the size of the arm and of the lymphatics of the mesocolon to the diameter of half an inch to nearly an inch. Nocard records two cases in the horse, one of a reticular lymphangioma of the sheath, and the other of dilatation of the lymph vessels accompanying the saphena vein on the inside of the thigh. This formed small, soft, fluctuating, extremely irregular tumors, completely covering the vein for a space of about four inches.
In both cases the dilatations were surrounded by a thick layer of connective tissue filled with liquid. Virchow records a case of a new-born calf in which a thrombosis of the external jugular vein caused obstruction of the mouth of the thoracic duct, and a consequent extreme distension of all the splanchnic lymph vessels with a slightly sanguinolent fluid. The intestines especially were covered everywhere with broad, bead-like canals, arranged so closely together that the intervening tissue could be scarcely recognized.
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.