Challenging the Gold Standard: Endohepatology for the Diagnosis of Presinusoidal Portal Hypertension

We report a 52-year-old patient referred for evaluation of abnormal liver tests, with extensive etiological workup negative. Abdominal CT and MRI revealed hypertrophy of the left hepatic lobe, nodular liver contours, and ascites (SAAG 1.7; total protein 1.8 g/dL). Upper endoscopy showed no stigmata of portal hypertension. A dual interventional radiology procedure was performed. Transjugular liver biopsy (LB) (18G) was non-diagnostic, and hepatic venous pressure gradient (HVPG) was normal (HVPG 3 mmHg; wedged hepatic venous pressure [WHVP] 13 mmHg; free hepatic venous pressure [FHRVP] 10 mmHg). Given suspicion of pre-sinusoidal portal hypertension, endoscopic ultrasound (EUS) was performed (Arietta 850, Fujifilm Healthcare, Tokyo, Japan). EUS showed blunting of the left lobe tip, irregular contours, and ascites. Endoscopic "palpation" revealed an indentation of 2.0 mm (abnormal). Shear-wave-elastography (SWE) of the left lobe was normal at 6.04 kPa, but other areas showed 10.5-11.1 kPa (abnormal). No splenomegaly, but the mean SWE was 31.9 kPa (abnormal). EUS-guided portal pressure gradient (EUS-PPG), measured with EchoTip Insight™ FNB needle (Cook Medical, USA), was elevated (PPG 8 mmHg; mean hepatic vein pressure 4.0 mmHg; mean portal vein pressure [PVP] 12.0 mmHg). Targeted EUS-guided biopsy of the left lobe (Acquire™ 19G FNB needle, Boston Scientific, USA) showed vague liver nodular transformation with alternating regenerative and atrophic hepatocytes, consistent with nodular regenerative hyperplasia (NRH). Due to refractory ascites, TIPS placement was proposed. Pre-TIPS evaluation showed mildly elevated HVPG (6 mmHg), while immediate post-TIPS assessment revealed elevated HVPG (HVPG 11 mmHg; PVP 20 mmHg; FHRVP 9 mmHg). Ascites was controlled with TIPS.