Ramkumar Subramaniam, Kharshiing Teikupar
Pathology, Woodland Hospital, Shillong, IND.
Obstetrics and Gynaecology, Woodland Hospital, Shillong, IND.
Cureus. 2021 Feb 21;13(2):e13472. doi: 10.7759/cureus.13472.
Subinvolution of the implantation site is a significant contributor to delayed postpartum hemorrhage (PPH). There is immense literature documenting the histologic features, development, and involution of the uteroplacental site; however, practice-oriented literature on subinvolution of the implantation site is sparse. In the present study, we briefly review the physiologic characteristics associated with the normal development and involution of uteroplacental arteries and the proposed pathophysiologic attributes of subinvolution. Furthermore, we engage in a comparison of the condition with preeclampsia. Herein, we report a case of postpartum vaginal bleeding that persisted for two weeks following cesarean delivery. The bleeding was nonresponsive to conservative treatment. Sonography performed revealed that a heterogeneous intrauterine vascular mass measuring 14.6 × 9.2 × 10.4 cmwas present, distending the uterine cavity. The presence of retained products of conception could not be ruled out. Therefore, to further confirm the condition, the patient underwent an emergency hysterectomy. Gross examination showed an enlarged and boggy uterus with numerous dilated and ecstatic thrombosed blood vessels in the implantation site of the endomyometrium. Histologic and immunohistochemical examination of the implantation site revealed the presence of persistently patent uteroplacental arteries with variable degrees of thrombosis adjacent to normally involuted vessels. Hence, a diagnosis of placental site vessel subinvolution (VSI) was established in this case. We also reviewed the related literature to illustrate the informative histologic findings of subinvolution. Preparing the ground for diagnosing subinvolution is important as this process defines that the cause of delayed postpartum uterine bleeding is idiopathic, rather than iatrogenic.
着床部位复旧不全是导致产后出血延迟的重要原因。有大量文献记录了子宫胎盘部位的组织学特征、发育及复旧过程；然而，关于着床部位复旧不全的实用性文献却很稀少。在本研究中，我们简要回顾了与子宫胎盘动脉正常发育和复旧相关的生理特征以及复旧不全的病理生理特征。此外，我们还将这种情况与子痫前期进行了比较。在此，我们报告一例剖宫产术后持续两周的产后阴道出血病例。保守治疗对此出血无效。超声检查显示宫腔内有一大小为14.6×9.2×10.4 cm的不均匀血管性肿物，使宫腔扩张。不能排除有妊娠物残留。因此，为进一步明确病情，患者接受了急诊子宫切除术。大体检查显示子宫增大、质地软，子宫内膜肌层着床部位有许多扩张、充血的血栓形成血管。对着床部位进行组织学和免疫组化检查发现，与正常复旧的血管相邻处存在持续开放的子宫胎盘动脉，并伴有不同程度的血栓形成。因此，本例诊断为胎盘部位血管复旧不全（VSI）。我们还回顾了相关文献以阐述复旧不全的重要组织学发现。为诊断复旧不全做好准备很重要，因为这一过程明确了产后子宫出血延迟的原因是特发性的，而非医源性的。
