What Causes Hepatic Surface Nodularity in Fulminant Hepatic Failure?

The objective of a recent study was to assess the frequency and cause of hepatic surface nodularity in patients with fulminant hepatic failure.

The results have shown that a nodular liver is commonly seen in patients with fulminant hepatic failure, and this is usually secondary to a combination of confluent regenerative nodules and necrosis.

Design
Retrospective analysis.

Participants/Methodology
This study was comprised of 35 patients who had undergone liver transplantation for fulminant hepatic failure. There were a total of 38 ultrasound and two CT studies that were performed prior to transplantation. CT examinations consisted of an unenhanced scan, followed by enhanced images obtained at 20, 45, and 80 seconds following IV contrast administration.

Ultrasound and CT images were reviewed independently by two different radiologists. Presence or absence of hepatic surface nodularity and ascites was recorded. Following transplantation, explanted livers were reviewed by two pathologists. Causes of fulminant hepatic failure included hepatitis, both viral and autoimmune, drug toxicity, Wilson’s disease, and idiopathic.

Duration of illness for this study was defined as the number of days from onset of fulminant hepatic failure and the date of initial imaging. The highest liver enzyme levels between illness onset and transplantation were also recorded.

Results
There were 15 of 35 patients with fulminant hepatic failure who had hepatic surface nodularity on ultrasound. Repeat ultrasounds, as well as CT scans performed in two of these patients, also demonstrated surface nodularity. However, none of these patients had cirrhosis at explant histopathology.

There was one patient with a smooth liver surface who was found to have cirrhosis at histopathology.
There were 12 of 14 patients with surface nodularity, and one of 19 patients with a smooth liver surface who had a combination of alternating foci of confluent regenerative nodules and necrosis.

Presence of ascites at time of ultrasound evaluation was not found to be significantly different between patients with or without a nodular liver surface.

Reviewer’s Comments
The results of this study are useful in demonstrating that hepatic surface nodularity in patients with fulminant hepatic failure is not a reliable sign to make a diagnosis of cirrhosis. As noted, this has important clinical implications, as acute-on-chronic liver disease receives a lower priority for organ transplantation if the patient has a diagnosis of cirrhosis.

Therefore, one should use caution in diagnosing cirrhosis solely based on presence of surface nodularity in the setting of fulminant hepatic failure. A limitation noted in this study was that the surface nodularity was not objectively defined or quantified.

Author:
John C. Sabatino, MD, MSD

Reference:
Poff JA, Coakley
FV, et al. Frequency and Histopathologic Basis of Hepatic Surface Nodularity in Patients With Fulminant Hepatic Failure.
Radiology; 2008;249
(November): 518-523.