Extrahepatic Immunological Disorders May Be Caused by Hepatitis
C
Hepatitis Weekly via Individual Inc. :
Peripancreatic adenopathy in chronic hepatitis C virus (HCV) is an
important diagnostic sign and may indicate an involvement of
hepatitis C in still unexplained extrahepatic immunological
disorders.
"The association between an increase in lymph
nodes and hepatitis C positivity on screening, and the negative
response to this screening in chronic hepatitis B surface antigen
(HBsAg) carriers, may not be merely expression of a non-specific
inflammatory reaction to the infection and the viral hepatic
location," researcher S. Neri et al. wrote ("Peripancreatic
Lymphoadenopathy and Extrahepatic Immunological Manifestations in
Chronic Hepatitis C," European Journal of Clinical Investigation,
September 1996;26:665-667). "It may confirm the marked
lymphotropism shown by the hepatitis C virus and indicate more
complex immune system involvement, especially regarding the other
coexisting signs of immune system involvement related to the
presence of intrahepatic cellular aggregates detected in our
study."
The cloning of hepatitis C virus (HCV) genome
and the introduction of tests to detect serum antibodies against
its structural and non-structural antigens have revealed that HCV
is the most important viral agent in community-acquired and
post-tranfusional non-A and non-B hepatitis. The use of molecular
biology techniques, such as polymerase chain reaction (PCR), has
located distinct areas in the genome of this single allele RNA
virus. The heterogeneity in the nucleotide sequence of some of
these gene regions (putative antigens in the NS5 core, etc.) has
allowed this virus to be subdivided into at least four genotypes.
Abdominal ultrasonography has revealed increases in the size of the
pancreas, coeliu and hepatic hilum lymph nodes in acute viral
hepatitis and in 80- to 90 percent of anti-HC-positive patients
with chronic infection. Elevated titres of serum anti-HC antibodies
have been observed in subjects with immune system disorders, such
as mixed essential cryoglobulinemia and Sjorgren's
syndrome.
In this study Neri et al. sought to determine
the role of peripancreatic lymph node swelling in systemic
immunological alterations during chronic HCV. The prospective study
was carried out in a university hospital. Clinical, hematochemical
and ultrasonographic findings in 182 patients were studied.
Ultrasonography was performed by the same operator and the findings
were evaluated blind without the operator knowing the clinical and
hepatological parameters.
Hepatitis B virus (HBV) markers, anti-HCV
antibodies, LKM1, cryogloblinemia, rheumatoid factor, and
anti-tissue antibodies were determined. Liver biopsy was carried
out in 43 of the 182 patients. One or two pathological
peripancreatic lymph nodes (PLNs) were present in 30 of the 182
patients and, of the 30, 28 were anti-HCV positive. Only one
patient in the non-PLN group was positive for anti-HCV, there being
statistical significance between the PLN and non-PLN groups. In
HCV-positive patients, extrahepatic immunological manifestations
were observed (cryoglobulinemia; positivity to anti-smooth muscle,
antinuclear and antimitochondrial antibodies; positivity to
rheumatoid factor and LKM1). In five patients the presence of focal
lymphocytic aggregates was detected by biopsy, whereas one patient
presented typical ocular lesion of Mikuliez's syndrome. "Our
results may confirm the marked lymphotropism shown by the HCV virus
and indicate more complex immune system involvement, especially in
view of the coexisting signs of immune system involvement related
to the presence of intrahepatic cellular aggregates detected in our
study," Neri et al. wrote. "We believe that the peripancreatic
adenopathy in chronic HCV hepatitis is an important diagnostic sign
and may indicate an involvement of the C virus in the still
unexplained extrahepatic immunological disorders."
The corresponding author for this study is
S. Neri, Istituto di Medicina Interna e Medicina d'Urgenza,
Ospedale S. Marta, Via Clementi 36, 95124 Catania, Italy.
Source: Hepatitis Weekly