Page 213 - AIDSBK23C

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HEPATOBILIARY SYSTEM PATHOLOGY IN AIDS

The liver is frequently involved by a variety of diseases in patients with AIDS. At
autopsy, the liver is involved by opportunistic infections and neoplasms in about one third of
AIDS cases but liver failure is an uncommon cause of death, occurring in less than 1% of AIDS
cases. There may be a history of chronic liver disease from viral hepatitis, particularly in persons
with a history of injection drug use. Chronic alcoholism may occur more often in persons with a
history of injection drug use. If chronic liver disease is present, it is probably part of a process
that preceded HIV infection, but the clinical course may be more aggressive than in the
non-HIV-infected patient.[871,872,873,874]
HIV-1 has also been identified within Kupffer cells, hepatocytes, hepatic stellate cells,
and sinusoidal endothelial cells in liver, but infection of these cells does not represent a major
reservoir for HIV. HIV can induce hepatocyte apoptosis via gp120 signalling through CXCR4 in
the absence of infection. Hepatocyte apoptosis can trigger pro-fibrotic activity of hepatic stellate
cells activity.[874]
Moderately elevated aminotransferase levels are found in one half to three fourths of
adults with AIDS, but such elevations do not necessarily correlate with significant pathologic
findings, or they may be due to alcoholic liver disease or hepatitis. Both opportunistic infections
and the pharmacotherapy for such infections may lead to transaminasemia. Alkaline
phosphatase can be increased in half of AIDS cases, and the most common cause is hepatic
granulomata. Jaundice is not common, appearing in the course of AIDS in about 10% of
patients. Abnormal liver function tests are unusual in pediatric AIDS. Lactate dehydrogenase is
often elevated, but this can occur with just about any opportunistic infection or neoplasm. Liver
biopsy may yield diagnostic information, particularly when there is fever of unknown origin or
the alkaline phosphatase is greatly increased, but the liver is only rarely the sole site of a
significant opportunistic infection or neoplasm. Other tissue sites may be sampled prior to
liver.[871,872,874]
In pediatric cases, granulomas are less frequent but giant cells more numerous, and
lymphoplasmacytic infiltrates can be present in association with lymphocytic interstitial
pneumonitis of lung. Focal fatty change is often present, sometimes with hepatocyte necrosis.
Other frequent findings include portal chronic inflammation, portal fibrosis. Chronic active
hepatitis is not seen. M avium-complex may produce a pseudosarcomatous reaction.[871,875]

HEPATITIS B.-- In Western Europe and the U.S., hepatitis B virus (HBV) infection has
been found in 6 to 14% of the overall population, including 4 to 6% of heterosexuals, 9 to 17%
of men who have sex with men, and 7 to 10% of injection drug users. [876] Vertical
transmission is a function of the incidence of congenital HIV infection. Worldwide, about 90%
of HIV-infected persons have evidence for past HBV infection, and 10% have evidence for
chronic HBV infection. Persons who are coinfected with HBV and HIV are less likely to clear
the hepatitis virus than immunocompetent persons, leading to higher rates of chronic HBV
infection, higher HBV DNA levels, and accelerated fibrosis progression to end-stage liver
disease.[877]
Serum aminotransferase levels may be lower in patients with HIV and HBV coinfection.
Progression to AIDS results in a decreased hepatitis B surface antibody titer and a greater
likelihood of reactivation of latent infection or reinfection with another viral subtype. Evidence