Idiopathic Postoperative Intra-abdominal Fluid Collection with Features of Ascites Following Cesarean Section: A Rare Case Report

Postoperative intra-abdominal fluid collection with features of ascites following cesarean section is exceedingly rare and poses a diagnostic challenge, as etiologies range from iatrogenic visceral injury to infection, chylous leakage, preeclampsia-related hypoproteinemia, and peritoneal malignancy. In many instances, however, no clear cause is identified despite extensive evaluation. A 37-year-old woman, six weeks after lower-segment cesarean section, presented with a 15-day history of progressive right-sided abdominal distension and lower abdominal pain. Imaging revealed a right iliac fossa fluid collection, for which a pigtail catheter drained 400 mL of serous fluid, followed by steadily decreasing output. CT abdomen showed free fluid surrounding bowel loops without evidence of bowel, urinary tract, or vascular injury. Laboratory workup, liver Doppler, hepatitis serologies, and malignant cytology were unremarkable. The patient remained hemodynamically stable and improved with supportive care. The catheter was removed on day six, and she was discharged with the diagnosis of idiopathic postoperative intra-abdominal fluid collection. With major causes excluded, a probable idiopathic inflammatory or allergic peritoneal reaction after exclusion of major causes, a benign entity previously described after gynecologic and obstetric procedures. Idiopathic postoperative intra-abdominal fluid collection with features of ascites is rare but resolves with drainage and supportive care. Early recognition prevents unnecessary surgical intervention. • Rare case of idiopathic ascites following cesarean section. • Patient developed abdominal distension six weeks post-LSCS. • Imaging showed intra-abdominal fluid without organ injury. • Pigtail catheter drainage led to rapid clinical improvement. • Supportive care resolved condition without surgical intervention