Serial transmission of spongiocytic hepatitis to woodchucks (possible association with a specific delta strain).

BACKGROUND/AIMS: Outbreaks of severe hepatitis have been reported from Africa and South America. Description of the cases has shown the histological hallmark to be the presence of ballooning hepatocytes with fat drops surrounding the nucleus (spongiocytes or morula cells).

METHODS

Experimental reproduction of this syndrome for the verification of a possible role of a specific HDV strain was performed by the inoculation of serum and liver extracts from African patients (Bangui-Central African Republic), who died with this syndrome, into American woodchuck carriers of WHV (WC 231,144), the results of which were then compared with animals inoculated with a reference wild HDV strain (WC 300,173,154), and those which received material from a European fulminant HDV case (WC 88,93).

RESULTS

Following the initial inoculation, the animals receiving African inocula had a delayed anti-HDV seroconversion, high mortality and showed the presence of spongiocytes, while the other animals had a classical evolution of HDV superinfection in woodchucks. Furthermore, the African inocula caused less inhibition of WHV replication, as well as a predominant cytoplasmic expression of HDAg, in contrast to the animals which received the other inocula. The second passage experiments gave similar results.

CONCLUSIONS

We conclude that this peculiar form of HDV fulminant hepatitis can be experimentally reproduced and might be specifically related to a more pathogenic strain.