Treatment of subacute hepatitis B with lamivudine : a pilot study in Serbia Le č enje subakutnog hepatitisa B lamivudinom : pilot studija u Srbiji

Background/Aim. The incidence of acute hepatitis B viral (HBV) infection in adults has increased in recent years in Serbia. Most icteric patients with acute hepatitis B resolve their infection and do not require treatment. Fulminant hepatitis B is a severe form of acute infection complicated by encephalopathy and liver failure. Subgroups of fulminant hepatitis B including hyperacute, acute and subacute are defined by the interval between jaundice and encephalopathy. Fulminant hepatic failure or subacute hepatitis B infection we observed in about 1% of all cases. In cases of fulminant hepatic failure or subacute form of HBV infection orthotopic liver transplantation can be life-saving operation, but in our country this procedure is difficult to achieve. Lamivudine has been established as a safe and effective antiviral agent for the treatment of chronic HBV hepatitis. Methods. In our pilot study performed at the Institute of Infectious and Tropical Diseases in Belgrade, Serbia in the period between 2002 and 2006 we treated 10 patients with clinically verified subacute HBV infection with lamivudine, 100 mg orally per day. Results. The most of the treated patients (9/10; 90%) survived subacute form of hepatitis B. After a few weeks of the treatment serum aminotransferase levels and other liver-function tests were normalized. Also, after a four-month lamivudine treatment all the patients lost HBsAg. Lamivudine was discontinued after six months in all the patients. In addition, six months after lamivudine was discontinued the patients remained well with normal results on liver-function tests. Conclusion. The obtained results suggest significant efficacy of lamivudine in patients with subacute hepatitis B. Also, we suggest that lamivudine therapy should be administered early in progression of subacute disease since it could be life-saving treatment in some patients, especially in the countries (like Serbia) where orthotopic liver transplantation is difficult to achieve.


Introduction
Most patients with acute hepatitis B resolve their infection and do not require treatment.Fulminant hepatitis B is defined as severe form of acute infection complicated by liver failure and encephalopathy.Subgroups of fulminant hepatitis B including hyperacute, acute and subacute are defined by the interval between jaundice and encephalopathy.Subacute hepatic necrosis is characterized by a more protracted acute course and transition to chronic hepatitis with ongoing hepatitis B virus (HBV) replication.Patients with fulminant hepatitis (including acute and subacute forms) should be considered for liver transplantation, if appropriate 1,2 .There are no controlled trials of lamivudine or adefovir dipivoxyl for patients with acute fulminant or subacute fulminant hepatitis.Anecdotal reports suggest some efficacy of lamivudine in these patients, and carefully administered therapy could be tried, if administered early, and if there is evidence of ongoing HBV replication 3,4 .Lamivudine, a nucleoside analogue, approved by the Food and Drug Administration (FDA) in 1998, is the negative enantiomer of 2'3' dideoxy-3'-thiacytidine, and inhibits HBV DNA synthesis at a dose of 100 mg daily 1 .

Methods
In a period between 2002 and 2006 at the Institute of Infectious and Tropical Diseases in Belgrade, Serbia we treated with lamivudine 10 patients (5 males and 5 females) who developed subacute hepatitis B. Mean age of the treated patients was 55 years (range 38-77 years).At first hospitalization all the patients had acute icteric hepatitis B according to serologic tests and they were positive for hepatitis B surface antigen (HBsAg), IgM antibodies to hepatitis B core antigen, and hepatitis B antigen (HBeAg).The use of polymerase chain reaction revealed the presence of HBV DNA.The tests for IgM antibodies to hepatitis A virus, antibodies to hepatitis C virus, and antibodies to hepatitis delta virus were negative.HIV infection was excluded by ELISA (Enzyme-Linked Immuno Sorbent Assay) test.All values described in the text are expressed as mean ± standard error of the mean (S.E.M.) of N observations.Each data points at figures represent biochemical parameters obtained from separate measuring in separate patients.Statistical analysis was carried out using GraphPad Prism/Instat 1.1 (GraphPad Software, California, USA) and Microsoft Excel 2003.For illustrations we used Microsoft Office Document Imaging.

Results
The patients were admitted for the second time to the hospital because of acute exacerbation of the disease with jaundice, ascites, coagulopathy and developed signs of encephalopathy.Mean time between first onset of the disease and second hospitalization was 53 days (range 39-72 days).On second admission to hospital mean levels of abnormal laboratory analyses were: alanine aminotransferase level (ALT) 1270 ± 178 IU/L, aspartate aminotransferase level (AST) 1035 ± 153 IU/L, bilirubin 426 ± 70 µmol/L, prothrombin time (PT) 31.9 ± 2.02% (normal range is 70-100%) and international normalized rativ (INR) 2.4 ± 0.161 (Table 1).At this stage, and because of the threat of subacute hepatic failure, we started treatment with lamivudine at a dose of 100 mg per day after obtaining written informed consents.Beside lamivudine, patients were treated with the usual therapy: fresh frozen plasma, mannitol solution iv 20%, glucose solution, iv 10%, lactulose orally, H2 blockers, etc. Gradually, the aminotransferase and bilirubin levels decreased and after about six weeks the patients were discharged (mean time of second hospitalization was 45 days-range between 20 and 66 days) (Figure 1, A-C).
A 44-year old female patient died despite the therapy on the day 51 of the second hospitalization.According to the report of her general practitioner she had not preexisting chronic liver disease.Necropsy showed submassive necrosis, portal inflammation, intralobular inflammatory infiltration with neutrophils, lymphocytes and ceroidophages and signs of liver cells regenerations (Knodell's Histologic Activity Index Score = 18).All other patients were discharged with folowing laboratory results: mean value of ALT 84.8 ± 9.1 IU/L, AST 73.6 ± 5.2 IU/L, bilirubin 61.9 ± 5.2 µmol/L and PT 61.7 ± 3.4 %.The test for HBsAg remained positive at that time.Clinical condition of the treated patients remained stable during the treatment.Lamivudine was well tolerated, with a few reported adverse events.Only one patient had fatigue and nausea.After four months of the treatment all the patients lost HBsAg and lamivudine was discontinued after 24 weeks.Each of the nine patients remained well, with normal results on liver-function tests and undetectable serum HBV DNA levels.Also, six months after lamivudine was discontinued in all the patients HBsAg was no longer detected.

Discussion
The pattern of liver failure is important for management decisions and should be recognized whether classified as fulminant or subfulminant (jaundice and encephalopathy less or more than 2 weeks), fulminant or late onset (less or more than 8 weeks), or hyperacute (0-7 days), acute (8-28 days) or subacute (29 days to 12 weeks).Late onset hepatic failure is the term that refers to a group of patients in whom encephalopathy develops after an illness of more than 4 weeks, but less then 12 weeks, from the first symptoms in the absence of pre-existing liver disease.Nausea, malaise and abdominal discomfort followed by ascites, encephalopathy and renal impairment.Survival was about 20% without transplantation 5 .
Lamivudine has been approved for the treatment of chronic hepatitis B, and, also, it has been considered as possible drug for treatment of polyarteritis nodosa associated with acute hepatitis B 1,6 .Similar results were published by Tillmann et al. 7 in multicentric study and by Schmilovitz-Weiss et al. 8 in pilot study.The goals of lamivudine treatment in cases of subacute form of HBV infection are the prevention of hepatic decompensation and fatal outcome and, in some patients, its use represents adequate replacement for orthotopic liver transplantation, which still remain best medical treatment for these patients.As the mentioned authors, we also started treating our patients with subacute hepatitis B with lamivudine to decrease the risk of fatal outcome.During the therapy patients were recovered within a few weeks without advancsment of the disease.Also, we have seen no adverse events after starting lamivudine therapy in these patients.Altogether these data indicate that early administration of lamivudine is safe and might be beneficial in patients with subacute hepatitis B 9 .According to our results lamivudine treatment should be continued until HBsAg is cleared, i. e. until loss of detectable levels of HBV DNA, loss of HBsAg and the appearance of antibody to HBsAg in the serum.
Also, we consider that a controlled prospective multicenter trail is warranted.However, having in mind these very promising results, we would not consider a placebo control in the setting of subacute hepatitis ethically feasible.

Conclusion
Our findings suggest that use of lamivudine should be considered in patients with subacute hepatitis B whenever it is possible due to preventing liver transplantation, especially in countries where liver transplantation is not routine procedure.

Fig. 1 -
Fig. 1 -Serum activity of alanine aminotransferase (A), bilirubin levels (B) and prothrombin times (C) were measured in all the patients during lamivudine treatment and follow-up period.Each data points at figures represent biochemical parameters obtained from separate measuring in separate patients.