Case report
A 57-year-old woman was diagnosed with malignant lymphoma in July 2000
after a positive stool occult blood test during a physical examination,
and rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone
(R-CHOP) chemotherapy was administered. During the two courses of
chemotherapy, blood tests confirmed abnormal liver enzyme levels. The
patient was asymptomatic, no new medications were started, and there was
no significant medical history. Laboratory tests revealed no signs of
chronic liver hepatitis. The results of liver function tests were as
follows; aspartate aminotransferase, 395 (10-42 U/L), alanine
aminotransferase, 235 (13-30 U/L), alkaline phosphatase, 169 (38-113
U/L), and total bilirubin, less than 0.2 (0.4-1.5<mg/dl).
Hepatic synthetic function was normal. Ultrasonography of the liver was
normal, and contrast-enhanced computed tomography (CT) revealed no
organic abnormalities in the liver. Prior to referral to our hospital,
the patient had been suffering from anemia due to gastrointestinal
bleeding. She had received RBC transfusion at another hospital; it was
therefore surmised that her symptoms may be due to a
transfusion-transmitted infection. The patient was screened for
hepatitis A, B, and C virus, human immunodeficiency virus, herpes virus,
and cytomegalovirus. The results of all the screening tests were
negative. In addition, although the patient was of an age at which
autoimmune diseases are common, liver autoantibody test results were
normal. Therefore, autoimmune diseases such as primary biliary cirrhosis
and autoimmune hepatitis were ruled out. Since the patient had a history
of eating undercooked pork, we considered the possibility of hepatitis E
and measured HEV-RNA, which was positive at 1.63 × 102 IU/mL. A liver
biopsy was performed to confirm the diagnosis, which revealed
inflammatory cell infiltration including lymphocytes and histiocytes
mainly in zone 1, bile stagnation including the portal vein area, and
coagulation necrosis including the appearance of eosinophils, consistent
with the findings of hepatitis E. Several reports have reported the
initiation dose of ribavirin for hepatitis E, with a dose adjusted on
the basis of the estimated glomerular filtration rate or weight-adjusted
dose (1)
The patient was started on ribavirin 400 mg with a weight-adjusted dose,
and blood tests showed no apparent drug-related adverse events. After
the start of treatment, the HEV-RNA became almost undetectable (Figure
1); therefore, R-CHOP therapy was resumed. Positron emission
tomography/CT confirmed complete remission after six course of the
chemotherapy (Figure 2).