Postpartum Septic Pelvic Thrombophlebitis of the Ovarian Vein in the Context of Acute Pyelonephritis: Clinical Challenges in the Decision to Anticoagulate.

Septic pelvic thrombophlebitis (SPT) is a rare postpartum complication that can be life-threatening if not promptly diagnosed and treated. We present the case of a 34-year-old woman who presented to the emergency department (ED) seven weeks postpartum with abdominal pain, nausea, vomiting, and diarrhea. Imaging revealed SPT with right ovarian vein thrombosis and concurrent acute pyelonephritis. The patient was found to be in septic shock requiring intensive care, broad-spectrum antibiotics, vasopressor support (norepinephrine) following 4.5 L of intravenous fluid resuscitation, and intravenous heparin. Initial workup was significant for urinalysis concerning infection and imaging showing a subtle filling defect with enlargement of the right ovarian vein with surrounding inflammatory changes. Despite negative blood cultures, she remained febrile following antibiotic change, prompting escalation to meropenem and daptomycin. Anticoagulation was initially started with therapeutic intravenous heparin, discontinued when the thrombus was considered potentially incidental, and later resumed as therapeutic enoxaparin at discharge for three months due to persistent thrombus burden and ongoing postpartum risk factors. This case highlights the diagnostic and therapeutic challenges of SPT, particularly when it presents alongside other infections such as pyelonephritis. In the absence of definitive guidelines, management decisions, including the use and duration of anticoagulation, must be individualized based on clinical status and thrombotic burden. Our case underscores the diagnostic overlap between pyelonephritis and SPT and the clinical challenges in determining when to initiate anticoagulation.