The clinical profile of acute hepatitis A infection: Is it really so severe?


The Clinical Profile of Acute Hepatitis A Infection: Is It Really So Severe?

To the Editor:

The interesting editorial by Siłogren1 stresses the role of hepatitis A virus (HAV) as a cause of severe hepatitis and fulminant hepatitis, placing renewed focus on the issue of universal vaccination and suggesting that the policy of vaccinating only high-risk groups, which is currently adopted in the United States and in most western countries, be reconsidered.2, 3

In Italy, as in other economically developed areas, the epidemiology of HAV infection has changed drastically in the past 10 years, with a decrease in herd immunity and an increase in the number of susceptible adults and thus of symptomatic cases.4 Nonetheless, in our experience, the overall profile of the disease remains favourable, and fulminant and fatal cases are extremely rare. In particular, at the Domenico Cotugno Infectious-Disease Hospital of Naples, in which all cases of hepatitis in the metropolitan area are hospitalized, independently from their clinical complexity, and which is also the region's reference center for fulminant hepatitis, 1182 cases of HAV infection have been diagnosed in the past five years, based on serological evidence of immunoglobulin M anti-HAV (61% men; mean age, 16 ± 5 years; 4% of cases superimposed on subjects affected by chronic HBV or HCV infection). Although the clinical picture was serious for nearly one-third of these patients (22% with severe general symptoms; 20% with transaminase levels that were almost 30 times the normal values; 12% with serum bilirubin > 300 mmol/L; 6% with coagulopathy with international normalized ratio > 1.8; and 1.8% with a relapsing or a prolonged course), only 2 of them presented severe complications (i.e., pancreatitis and aplastic anemia), with resolution in both of them, and only 4 patients progressed to fulminant hepatitis.5. One of these patients, a pregnant women, required transplantation, and 3 recovered spontaneously; 1 of the latter 3 was suffering from chronic hepatitis C infection, and another had a history of low-dose acetaminophen intake, although nearly 20% of the patients without complications reported the use of this drug before the appearance of jaundice.

In other words, only 0.3% of the more than 1,000 consecutive cases of HAV infection progressed to fulminant hepatitis, and none of the cases was fatal. These data are consistent with reports from Italy's national hepatitis surveillance system, which indicate that only 1 death has occurred among the 11,063 cases of HAV infection from 1965 to 2000.6