S2565 An Incidental Liver Mass Waiting to Explore: Hydatid Cyst in a Pregnant Female

Abstract

INTRODUCTION: Human echinococcosis is a disease process caused by several species of tapeworms in the Echinococcus genus. These tapeworms utilize a variety of hosts that include rodents, herbivores and carnivores; humans are considered accidental hosts. This disease is very uncommon in the United States, and manifests most commonly with cystic liver lesions; but can spread to other organs as well. The liver cysts are slow growing and asymptomatic until they exceed 10 cm in size. Diagnosis is made with imaging and serologies. Here we present a case of a hydatid cyst in a pregnant female, with limited treatment options. CASE DESCRIPTION/METHODS: A 40 year old healthy Lebanese female, G3P2 at 11 weeks, presented with left lower extremity edema, dizziness and leg pain. Lower extremity ultrasound (US) revealed extensive thrombus, with subsequent CTPA revealing bilateral pulmonary emboli. Incidentally, a 7.1 cm hepatic mass was noted on the CTPA. Labs revealed a normocytic anemia with a hematocrit at 30.9% but were otherwise normal including liver function studies. Anticoagulation with enoxaparin was started, and she was transferred to a tertiary medical center for evaluation of the liver mass. There, she underwent a dedicated ultrasound of her abdomen which demonstrated a 7 cm mother cyst with multiple daughter cysts consistent with a hydatid cyst (Figure 1). Serological markers were sent and revealed a positive echinococcus antibody. Due to patient remaining asymptomatic and her gravid status; active surveillance was pursued. She underwent hepatic US every 3 months until delivery of a healthy girl. Over the course of her pregnancy, the cyst marginally increased in size, but her liver function tests remained normal and she remained asymptomatic. Post-partum, she underwent a modified puncture-aspiration-injection-reaspiration (PAIR) procedure. DISCUSSION: Hydatid cysts can result in pain, pancreatitis, rupture with further seeding, hemorrhage, fistula formation and systemic infection. These cysts can cause mass effect with compression of the biliary tree and portal vessels. The differential includes abscess, hemangioma, hamartoma and malignancy. Surgical treatment with adjunctive antiparasitic therapy can be utilized, but percutaneous therapy tends to have shorter hospital stays. Given the rarity of this disease in the United States and limitation of treatment during pregnancy; hydatid cysts should be considered in the differential of hepatic mass and actively monitored during pregnancy.Figure 1.: Abdominal Ultrasound.