E2879. Scintigraphic Shunt Studies in the Diagnosis of Hepatic Hydrothorax
  1. Nicholas Kemper; University of Louisville School of Medicine
  2. Henderson Jones; University of Louisville School of Medicine
  3. Nana Ohene-Baah; University of Louisville School of Medicine
  4. Bryan Glaenzer; University of Louisville School of Medicine
Hepatic hydrothorax (HH) is a rare complication of cirrhosis, portal hypertension, or severe ascites and commonly presents with a transudative pleural effusion, dyspnea, and pleuritic pain. The diagnosis is made in the presence of pleural effusion, excluding other causes such as infection, malignancy, or cardiopulmonary disease. Additional studies, including pleural fluid analysis, computerized tomography (CT), echocardiography, and abdominal ultrasound with Doppler, are often performed to confirm the diagnosis and exclude alternative causes. Our institution performs pleuroperitoneal shunt scintigraphy using 99mTc macro-aggregated albumin instilled into the peritoneal cavity to confirm transdiaphragmatic shunting. The current study was conducted to assess the validity of confirmatory testing using pleural fluid analysis and scintigraphic shunt studies in patients with HH.

Materials and Methods:
The current study was a retrospective cohort study of patients from October 2011 to August 2022. Clinical data, including patient presentation and outcomes, were obtained from patients who received pleuroperitoneal shunt studies or a diagnosis of HH. Patients were included if they received pleuroperitoneal shunt studies and pleural fluid analysis.

Thirty-eight patients received pleuroperitoneal shunt studies, with 17 of those also having pleural fluid analysis. Pleural effusions were most often large (13/17; 76%) and most often right-sided (12/17; 71%), followed by bilateral (3/17; 18%), then left-sided (2/17; 12%). Ascites was detectable in 88% (15/17) of patients. Shunt studies were positive in 53% (9/17) of cases. One case with an exudative pleural effusion and cirrhosis had a positive shunt study on the contralateral side. However, repeat shunt studies showed no ipsilateral pleuroperitoneal shunting or communication between pleural spaces, and the patient was determined not to have HH on the ipsilateral side. Pleural effusions were exudative in two other cases, both of which had negative shunt studies and were determined not to have HH. No patients were diagnosed with HH following negative shunt studies, and all patients diagnosed with HH also had positive shunt studies.

The data indicate that scintigraphic pleuroperitoneal shunt studies are sensitive and specific for diagnosing HH. Confirming the pathophysiology leading to HH is essential to identify patients who will benefit more from transjugular intrahepatic portosystemic shunting (TIPS) than medical management, and patients may benefit from increased utilization of these studies.