A Surprising Cause of Liver Abscesses in a Post-Chemotherapy Patient: Herpes Simplex Virus

Abstract

Herpes simplex virus (HSV) hepatitis is a rare complication of HSV infection, and a rare cause of hepatitis. It is often fatal, especially if the diagnosis and treatment are delayed. Herein, we describe the case of a 31-year-old female with a history of receiving cytotoxic cancer chemotherapy five months prior who presented with a one-week history of worsening abdominal pain and fever. She was noted to have an outbreak of genital herpes at the time of presentation. Computed tomography (CT) scan of the abdomen showed innumerable hypodensities compatible with hepatic micro-abscesses. A specimen from a subsequent liver biopsy revealed HSV-type cytopathic changes and nuclear staining with an anti-HSV immunohistochemical stain. She was initially started on high-dose oral valacyclovir for genital herpes and was noted to have rapid clinical improvement prior to the histopathologic diagnosis of HSV hepatitis. She achieved full recovery while on oral valacyclovir. This is the first reported case of HSV hepatitis treated with oral valacyclovir and the third reported case of HSV hepatitis mimicking pyogenic abscesses on abdominal imaging. With the high mortality rate associated with HSV hepatitis, one should consider the diagnosis in all patients with multifocal liver lesions of unknown etiology, especially if genital herpes is present at the time of presentation, or in patients who are immunocompromised.

Keywords: hepatic abscess; hepatic necrosis; hepatitis; herpes simplex virus (hsv); valacyclovir.

Figure 1. Computerized tomography of abdomen and pelvis with IV contrast.

There were innumerable small hypodensities throughout the liver, new from a prior PET CT imaging five months prior. These were concerning for microabscesses from bacterial or fungal infection. Nonspecific adjacent inflammatory changes were also apparent.

Figure 2. Photomicrograph of liver biopsy showing a zone of necrosis (left half of image, indicated by arrow) and a zone of viable hepatocytes (right half of image, indicated by arrowhead).

Magnification 100X (hematoxylin and eosin (H&E)).

Figure 3. Photomicrograph of liver biopsy section showing a degenerating hepatocyte with smudged chromatin and multinucleation consistent with viral cytopathic changes (arrow) in a background of necrosis and lymphocytic infiltrate.

Magnification 400X (hematoxylin and eosin (H&E)).

Figure 4. Photomicrograph of liver biopsy section with immunohistochemical staining for HSV-1/2 demonstrating positive nuclear staining in a multinucleated hepatocyte (arrow), magnification 200X. This stain does not differentiate HSV-1 from HSV-2.

Figure 5. Computerized tomography of abdomen and pelvis with IV contrast, six months after completion of a course of high-dose valacyclovir.

The liver was normal in size and morphology, with interval resolution of previously seen diffuse nodular hypoattenuating lesions.