Parametrial tumour causing hydronephrosis and hydroureter due to IgG4 mediated retroperitoneal fibrosis; A laparoscopic resection.

Abstract

Retroperitoneal fibrosis (RPF) is a disease that develops following inflammation and fibrosis of the retroperitoneum and other abdominal organs, which manifests with various local and systemic symptoms. It has several entities, namely the idiopathic RPF (IRPF), secondary RPF and Immunoglobulin G4-related disease (IgG4-RD). The role of a gynaecologist in the management of retroperitoneal fibrosis is highlighted in this case of a parametrial tumour causing retroperitoneal fibrosis and hence leading to hydronephrosis and hydroureter as a consequence. A 49-year-old woman presenting with a symptom cluster suggestive of acute pyelonephritis was found to have reduced eGFR. Elevated levels of inflammatory markers indicated an inflammatory nature of the disease, in addition to a normochromic anaemia that could be due to chronic inflammation itself. CECT Neck, Chest, Abdomen and Pelvis revealed mild hydronephrosis with a distal narrowing and a retroperitoneal confluent mass. Investigations led to suspect an invasive left ovarian malignancy or an endometriotic nodule with ureteric compression, which was later thought to be unlikely with a normal CA-125 level. To obtain a better understanding, a cysto-ureteroscopy was performed where she was found to have an obstruction. Although stent placement is a reasonable temporary mode of symptom relief, this was proven unsuccessful. Surgical management was opted for considering the severity of her symptoms and the course of time it would take for medical management to take effect. In addition, laparoscopy would aid in the exclusion of other pelvic pathologies under direct vision and treat any if found concurrently. Consequently, a laparoscopic hysterectomy, bilateral salpingo-oophorectomy, left sided ureterolysis with careful resection of the densely adhered tumour surrounding the left cysto-ureteric junction was performed, followed by retrograde ureteric stenting. Histology revealed retro-peritoneal fibrosis, and further immunohistochemistry pointed towards a diagnosis of IgG4 related sclerosing disease. This was also supported by elevated levels of IgG, especially the IgG4 component. Disseminated RPF was subsequently excluded by CECT. Following surgery, she was started on high dose corticosteroids and the stent was left in place for six weeks. She is being kept on a maintenance dose of low dose corticosteroids without disease relapse. Regular follow-up with inflammatory markers, serum IgG4 levels and imaging demonstrate adequate response to corticosteroid therapy.