**3.2.2 Diagnosis**

Ureteral endometriosis should be included in the differential diagnosis of obstructive ureteral lesions in women, particularly those involving the lower third of the left ureter. Because a large percentage of ureteral endometriosis can result in loss of renal function due to asymptomatic obstruction, all patients with pelvic endometriosis should undergo the upper urinary tract imaging. Initial imaging may be ultrasonography as a noninvasive test to look for hydroureteronephrosis.Although, IVU may be a better test in high suspicious cases. Intrinsic disease appears in IVU as ureteral filling defects, whereas extrinsic disease causes smooth strictures. The exact location and volume of the disease can be defined through retrograde ureteropyelography, CT or MRI , which can be valuable for planning treatment.

The diagnosis of ureteral endometriosis requires a high index of suspicion and is aided by clinicians' awareness of the condition. The diagnosis of ureteral endometriosis is suggested by the finding of hydronephrosis in a patient with known or suspected endometriosis, particularly if symptoms consistent with ureteral involvement are present but, definite diagnosis can be reached through direct visualization and biopsy of implants. Histologic confirmation is the gold standard for diagnosis of endometriosis .

The differential diagnosis of ureteral endometriosis includes any conditions that result in hydronephrosis such as stones and malignancies.
