Correct answer is: Endometritis

Discussion

As there was still a slight suspicion of malignancy and the patient wanted a hysterectomy, the patient went on to have a total laparoscopic hysterectomy, bilateral salpingo-oopherectomy and pelvic lymphadenectomy. Histopathology confirmed a diagnosis of extensive necrotizing granulomatous endometritis, adenomyosis, and bilateral chronic necrotizing granulomatous salpingo-oophoritis.

Necrotizing granulomatous endometritis (NGE) is a rare but serious inflammatory condition of the uterine lining that can cause significant pelvic pain and infertility. Differentiating NGE from other conditions, such as hematometra, endometrial cancer, and endometriosis, is important for proper diagnosis and treatment. Ultrasound is a commonly used imaging modality that can help differentiate these conditions.

Hematometra is a condition where blood accumulates in the uterus due to an obstruction in the cervical or uterine canal. On ultrasound, hematometra appears as a fluid-filled cavity in the uterus with a smooth, echogenic lining and uniformly homogeneous myometrium.

Endometrial carcinoma is a malignant growth of the endometrial tissue that can cause abnormal vaginal bleeding and pelvic pain. On ultrasound, endometrial carcinoma appears as a thickening of the endometrial lining, often with irregular borders and heterogeneous echogenicity. There may also be masses or nodules within the endometrial cavity or myometrium. Unlike endometritis, endometrial carcinoma demonstrates washout in the delayed phase on CEUS examination.

Endometriosis is a condition where endometrial tissue grows outside the uterus, often on the ovaries or other organs within the pelvis. On ultrasound, endometriosis appears as well-defined masses that are hypoechoic or cystic in nature with diffuse low-level echoes within. Endometriosis and adenomyosis can also be a cause of elevated CA125. Adenomyosis can also cause irregularity of the endometrial lining with uniform appearance of the myometrium in early stages.

NGE, on the other hand, appears as multiple, small cystic spaces within the endometrial cavity(image 6) often with thickening and irregularity of the surrounding endometrium. These cystic spaces may contain fluid, debris, or necrotic tissue. On ultrasound, NGE can appear similar to endometriosis or endometrial carcinoma on B-mode imaging, however CEUS reveals no delayed washout. Endometritis may also show FDG uptake on PET/CT, where the degree of uptake varies by the severity and chronicity of the inflammation.

Conclusion

Contrast enhanced ultrasound is a safe and inexpensive imaging modality providing bed side diagnosis when used, and can aid in planning further management.

Conflicts of Interest

The authors declare no conflict of interest

References

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