When human filariasis causes inflammation of the lymphatic vessels and thickens the walls, the lymphatic vessels from the intestinal trunk to the thoracic duct are dilated, the valves in the vessels close incompletely and produce a dynamic obstruction, causing a blockage of lymphatic fluid and an increase in pressure in the lymphatic vessels, which can rupture at the weakest point. The common site of rupture is at the fornix of the renal pelvis, and a pelvic-lymphatic fistula may result. Etiology: Lymphadenopathy of various origins leads to mechanical or dynamic obstruction of the lymphatic vessels, which increases the pressure in the proximal lymphatic vessels and ruptures the lymphatic vessels under the mucosa of the renal pelvis, resulting in a pelvic-lymphatic fistula. In addition to filariasis other parasites such as encapsulated worms, Plasmodium, hookworms, and trichomonads can also cause lymphadenopathy and produce celiac disease. Examination: The most common site for rupture of the urinary lymphatics is the renal pelvis (because the kidneys have the most fragile lymphatics), followed by the ureter, and sometimes the bladder and posterior urethra. When in doubt, it is advisable to check the blood, urine and ultrasound first, so that most of them can clarify the situation, and if necessary, do MRI or imaging to clarify the situation.