Hepatitis
A (HAV)
Hepatitis D (HDV)
Hepatitis
B (HBV)
Hepatitis E (HEV)
Hepatitis
C (HCV)
Hepatitis G (HGV)
WEB WARNING:
We have found most hepatitis discussion sites on the web to be a waste of time, or worse. Try this introduction to the topic,
by an expert Board-certified specialist.
Viral hepatitis is
a disease as old as the history of Medicine. Hepatitis was described in the Babylonian Talmud in the Fifth Century BC, and
was referred to by Hippocrates over 2000 years ago. Despite this ancient knowledge, it was not until 1969 that the first human
hepatitis virus was isolated, Hepatitis B. This was followed quickly by the purification of Hepatitis A in 1973, and more
recently by the isolation of viruses C, D, E, and G. This is an introduction to the 6 major human hepatitis viruses—Viruses
A through G.
Although Viruses A
through E are often discussed, there are more than twenty other viruses which infect the human liver. These are not considered
"hepatitis viruses" as these other viruses tend to infect organs other than the liver more seriously. These include common
viruses such as cytomegalovirus, mumps, and rubella, as well as rare ones such as Lassa Fever and Yellow Fever viruses.
Incidentally, not
all "hepatitis" is caused by viruses. "Hepatitis" means "inflammation of the liver", and can be caused also by other types
of infection (bacteria, fungal, TB, etc.); toxic drugs; poisons; alcoholism; vascular disorders; and immune system diseases.
Hepatitis A (HAV)
Hepatitis A (HAV)
is caused by a RNA virus which is found in feces, saliva, semen, and blood of infected people. It is transmitted primarily
by the fecal, oral or sexual contamination, but can be passed rarely by blood transfusion or contaminated needles.
The illness typically
begins with jaundice (yellow skin), fever, and weakness occurring six weeks after the time of infection. Prior to the onset
of jaundice, there is often a period of mild illness for several days resembling the "flu" with tender lymph nodes (especially
in the neck), mild cough, mild diarrhea, or upper abdominal pain. Symptoms of hepatitis usually resolve in two to six weeks.
Rarely, patients experience
relapses (restarting of symptoms) for up to a year after the first illness; or there may be a prolonged phase with jaundice
lasting for 6 months. Rarely, a fulminate acute hepatitis occurs which often ends in death. Chronic Hepatitis A does NOT occur.
Efforts to prevent
Hepatitis A focus upon limiting exposure to the virus and giving a gamma globulin (antibody) injection to people exposed to
the virus. Vaccination to prevent Hepatitis A is very effective and is required for all school children in the United States.
We recommend that all adults be vaccinated (two injections are given into muscle), especially those likely to travel to endemic
areas such as Latin America, Africa, Eastern Europe, and Asia.
Treatment of Hepatitis
A includes rest, plenty of fluids, and avoidance of medications or herbs which might injure the liver. Patients with fulminate
liver failure are referred for emergency liver transplantation.
Hepatitis B (HBV)
Hepatitis B remains
one of the major causes of human suffering in the world despite a thorough understanding of its transmission and prevention.
It is a DNA virus and there are many serotypes (subtypes). Fortunately, antibody to the protein called "B surface antigen"
gives a person immunity to most HBV’s subtypes.
HBV can be acquired
parenterally (blood transfusions, contaminated needles) or sexually. The acute illness (jaundice, weakness, fever, nausea)
typically resolves after 2-4 weeks. In under one percent of cases, fulminate hepatitis occurs which is often fatal. One in
twenty infections results in chronic hepatitis, defined as persistent hepatitis virus six months after the onset of the acute
illness.
Chronic HBV infection can be entirely benign with normal liver blood tests ("chronic carrier state") or may
be an aggressive inflammatory process ("chronic active hepatitis") which can lead to severe scarring ("cirrhosis"). The risk
of liver cancer (hepatoma) is high in cirrhosis caused by HBV.
The 3-injection vaccine
for HBV is recommended for all school-aged children, for people exposed to HBV, and for some health care workers. These vaccines
are not derived from patients and carry NO RISK of giving someone hepatitis or AIDS virus.
Acute exposures, such
as needle stick injuries, infants born to infected mothers, and rape victims, are managed with the Hepatitis B vaccine and,
in addition, with Hepatitis B high-titer Immune Globulin injection (HBIG).
Interferon has been
approved for the treatment of biopsy-proven chronic active HBV. This treatment is administered as injections given daily
or three times a week for four months.
A new drug, Lamivudine,
is under intense investigation with respect to its role in the management of Hepatitis B. Two early studies investigated
if in combination with interferon there might be better outcomes. Such seems not the case. At present, much investigation
is directed at Lamivudine in a mono-therapy role. A recent article published in the New England Journal of Medicine
by the US Lamivudine Investigator Group (Dienstag et al. Lamivudine as Initial Treatment for Chronic Hepatitis B in The United
States NEJM 19993;41(17):1256-1269) suggest that one year of mono therapy with Lamivudine had positive effect with
respect to histology, virulence and biochemical features.
Unfortunately, liver
transplantation is not effective for HBV with current methods.
Hepatitis C (HCV)
Hepatitis C (HCV)
is a single-stranded RNA virus. In 1990, the partial genetic sequence of the virus was reported and the first diagnostic test
became available to detect antibodies to the virus in blood. These antibodies are not protective against the virus but are
a helpful marker of infection in that most people with HCV antibodies are actively infected and contagious. HCV is responsible
for most cases of what was previously called "Non-A, Non-B Hepatitis".
Risk Factors
For Transmission
· Blood Exposure, Needle Stick Injury or Transfusion
· Illegal Drug Use, Including "snorting"
· Tattoos or Body Piercing
· Sexually Active with Multiple Partners
· Transmission of HCV can occur by blood transfusions (now very rare), needle
· stick injuries to health care workers, and drug abuse through sharing of infected needles (most
common).
One of the mysteries
surrounding HCV is that the mode of transmission is not identified in more than 20% of cases. The spouses of infected people
are at slightly increased risk although the mechanism of transmission to spouses is not known. Transmission to spouses during
intercourse is so rare that condom use is usually NOT advised for a patient who is in a long-term relationship with one partner.
Certainly HCV is in blood, and sexual behavior should be considered dangerous where blood may be spread such as when there
is a cut or sore in the genital areas.
Acute Hepatitis C
develops approximately 6 to 10 weeks after infection. Patients may experience no symptoms or merely a mild flu-like illness
lasting a few days or weeks and usually without jaundice (yellow skin and eyes). Usually, liver blood tests are not measured
and Hepatitis C is not suspected or diagnosed until years or decades later.
Chronic Hepatitis
C disease occurs in 50-62% of cases; most of these people remain contagious for life. The majority of those with chronic HCV
have a relatively mild form, which seldom progresses; though the natural history is mild HCV is still under study. Of those
who develop chronic hepatitis, many develop aggressive hepatitis with gradual progression to cirrhosis (permanent scarring)
and liver failure. Unfortunately, most people with aggressive HCV disease have no symptoms until the late stages of cirrhosis.
The diagnosis of HCV
is usually an accident. Typically, a routine liver blood test will be found to be abnormal, and the physician then orders
the Hepatitis C antibody blood test. The virus itself can also be measured (HCV RNA), and this test has become helpful to
gastroenterologists managing drug therapy for HCV (see below). Liver biopsy, the most precise way to evaluate the severity
of HCV infection, is required for all patients prior to starting drug therapy.
Many studies have
shown that a medicine called interferon, given as an injection three times a week for 6 - 12 months, can improve liver blood
tests and the appearance of liver tissue when seen through a microscope (histology). This is the current standard treatment
for aggressive hepatitis C.
Therapy for
Hepatitis C
Many studies have
shown that a medicine called interferon, given as an injection three times a week for 6 - 12 months, can improve liver blood
tests and the appearance of liver tissue when seen through a microscope (histology).
Four brands of interferon
are available in the United States. This therapy is prescribed by liver specialists and requires careful patient education
and monitoring to be administered safely. The form of interferon used most often is Interferon alpha-2B (Intron-A). Approximately
one half of subjects treated with Intron-A respond with normalization or near-normalization of liver blood tests by six months.
Unfortunately, most will relapse by two years after completion of therapy, and many require long term low-dose treatment,
or other options. The long term, virus-free success rate with Intron-A is well under 10%.
Combination therapy
with two or more medicines is under intense study. In an article published in the New England Journal of Medicine
( McHutchinson et al. NEJM 1998:339(21) 1485-1550) McHutchinson's investigators reported undetectable serum virus levels
24 weeks after treatment with patients treated for 24 weeks with interferon alone at 6% and for patients treated with combination
therapy (Interferon & Ribavirin) to be 31%. In this same study, in-patients who where treated for 48 weeks with either
form of therapy, the results where 13% for mono-therapy with interferon and 38% for patients treated with combination therapy.
In general, the trend
in viral therapy seems to be directed at present with investigating different forms of combination therapy. Of note, several
large multi-center studies investigating the effectiveness of combination therapy will be releasing their data in the next
year, and we look forward to this data to better explain the added role of Ribavirin. At present, the combination of Ribavirin
with Interferon has replaced mono-therapy with interferon, but as with all things in medicine, there will most likely be a
different approach to therapy in the near future. Although not yet proven, the hope is that interferon therapy will prevent
the progression of the disease to cirrhosis and death.
Two years ago the
FDA approved a new form of interferon which was time released called peginterferon Alpha 2b, thus allowing patients
once a week injections vs. three times a week as had been the case . Until recently only one manufacture, Sherring
pharmaceuticals had FDA approval for this new form of long acting self released interferon, but as of last month Hoffman-LaRoche
pharmaceuticals introduced peginterfeon Alpha-2a, and in a recent clinical trial published in the New England
Journal of Medicine dated September 26th, 2002 (Vol.347,no.13,975-982), researchers Fried et al. compared these two different
manufactures interferon in hepatitis C patients. Early data may suggest improved response with peginterferon Alpha-2a, though
as has been the case with all new clinical trials with interferon based treatments, larger study groups will be needed before
the final answer is out. We are pleased now to have other pharmaceutical companies getting involved in the treatment
of hepatitis C, since the competitiveness between companies may extend new treatments to our patients with better and more
effective treatments in the future.
Other areas
of active clinical studies involve other types of cytokines such as IL-2, which has been reported to have benefit in HIV therapy
and IL-10 which may have some anti-fibrosis properties.
One of the newest
areas of interest, are those patients in whom some form of long term interferon based therapy has been given in advanced cases
of fibrosis. There is some early evidence that the use of interferon in such patients may retard...at least for a while.
the eventual progression to cirrhosis and decompensated liver disease and hence the need for transplantation. While
it is too early to say if long term administration of interferon based therapy may succeed in this, there are on going trials
in the U.S. to study this.
As with all clinical
studies, if one is considering becoming a participant, one should be cautious of several things. First, is
study participation in any way going to interfere with your health care insurance contract? Many HMO's and PPO's will
not cover clinical research trials, and if you become ill during such a clinical trial, your insurance carrier may not cover
those medical cost incurred by yourself. Be sure to have clarification of this point, and inquire whether the clinical
trial that you are going to participate in will cover such costs if needed. Second, many drug studies are in fact pseudo-marketing
ventures with the investigators and the drug manufactures, inquire about the type of study that you are considering with the
investigator. Do they have a financial incentive to enroll patients? Studies are designated as Phase 1,
2, 3 and 4. Phase 4 studies tend to be post drug (FDA) approval studies, and these you should be most leery of, since
they tend to be marketing studies usually funded by the marketing arms of the pharmaceutical industry and not by the research
sides of the industry. Phase 2 & 3 studies are usually pre-approval studies, and most often are funded by the research
divisions of the pharmaceutical industry. These studies ask such questions as to whether the drug really does what it
is intended to do, and what are the appropriate doses.
At present, all
patients who have chronic Hepatitis C should be vaccinated for both Hepatitis A & B if they do not already have immunity.
This , per a recommendation of the NIH and most leading experts in the field of hepatology.
The diagnosis of Hepatitis
C and all of these treatments are available from Borland-Groover Clinic physicians and their expert staff.
Treatment with interferon,
ribavarin, and other medicines is very difficult and expensive. For patients requiring therapy but unable to afford the medications,
many of the pharmaceutical companies involved in therapy have provided ways to get medications for free, one needs to
ask ones physician if this is an issue.
All patients have
complications, sometimes severe, while taking these drugs. Unfortunately, for patients with aggressive hepatitis C there often
is no good alternative as other approaches (diets, herbs, exercise etc.) are ineffective. People with hepatitis C should discuss
these issues in detail with their primary care physician or Board-certified gastroenterologist.
Liver transplantation
is considered when hepatitis C results in end stage cirrhosis and liver failure. The time from initial infection to liver
failure is 20- 40 years. |
Hepatitis D (HDV), the Delta Virus
Hepatitis D (HDV or
Delta) is a defective RNA virus which cannot survive on its own. It only infects liver cells which are co-infected with Hepatitis
B virus.
The Delta virus takes
advantage of enzymes of HBV in order to replicate and to acquire a surface coating which allows it to survive outside the
liver.
The virus is transmitted
parenterally (transfusions, dirty needles, etc.) or through sexual contact. When chronic carriers of HBV are super infected
with HDV, a more aggressive or even fulminant illness may occur. Neither interferon nor transplantation is effective for hepatitis
D.
Hepatitis E (HEV)
The first reports
of the isolation and partial molecular sequencing of Hepatitis E were published in 1990. HEV is similar to hepatitis A in
many respects: it is an RNA virus, is transmitted by the fecal-oral routes, and causes acute (but not chronic) illness. This
agent appears to be the principle cause of epidemic, water-borne hepatitis in the Third World. A few cases have been reported
in the United States among travelers recently returned from Mexico or Asia. Generally a benign illness, the greatest risk
is to pregnant women for whom the case fatality rate is approximately 20%. A 1997 report suggests that a strain of HEV may
be a rare cause fatal fulminant hepatitis in the United States.
Hepatitis G (HGV)
No Hepatitis
F virus has been named, but Hepatitis G (HGV) was newly described in 1995.
This virus is very
similar to the Hepatitis C (HCV) : both are RNA viruses and 25% of their molecular structures are identical. HGV is transmitted
from person-to-person by the same methods as HCV (see above), and approximately one in five people infected with HCV also
carries HGV.
Fortunately, it appears
that HGV is an "innocent" virus in that it is commonly found in livers but does not seem to cause disease or lead to complications.
Patients with HCV and HGV confection are no more ill than those with HCV infection alone.
Blood tests are available
to detect antibodies to HGV but these are ordered rarely by physicians. No therapy has been described although it does not
appear that therapy is necessary.
The Future? Hepatitis H?
The next five years
should bring more widespread use of the Hepatitis A and Hepatitis B vaccines, and progress towards the development of a HCV
vaccine. There will be better medication regimens for HCV, with options using 2 or more medicines in combination. Long term
survival rates will improve for liver transplantation.
Lastly, most experts
believe that more viruses remain to be discovered to explain the 10 to 15% of patients whose chronic hepatitis is unexplained. One of these is likely to be named
the new Hepatitis H virus. | |
|
|
Second article on Hepatitis C: |
|
FROM: http://www.borland-groover.com/articles/HepCandHIV.htm
Article by Kyle P. Etxkom, M.D. F.A.C.P.
HEPATITIS C AND HIV: Is There an Argument to Treat?
Hepatitis C (HCV) is a single-stranded
RNA virus. In 1990, the partial genetic sequence of the virus was reported and the first diagnostic test became available
to detect antibodies to the virus in blood. These antibodies are not protective against the virus but are a helpful marker
of infection in that most people with HCV antibodies are actively infected and contagious. HCV is responsible for most cases
of what was previously called "Non-A, Non-B Hepatitis".
Risk Factors For Transmission
· Blood Exposure, Needle Stick Injury or Transfusion
· Illegal Drug Use, Including "snorting"
· Tattoos or Body Piercing
· Sexually Active with Multiple Partners
· Transmission of HCV can occur by blood transfusions (now very rare), needle
· Stick injuries to health care workers, and drug abuse through sharing of infected needles (most common).
One of the mysteries surrounding
HCV is that the mode of transmission is not identified in more than 20% of cases. The spouses of infected people are at slightly
increased risk although the mechanism of transmission to spouses is not known. Transmission to spouses during intercourse
is so rare that condom use is usually NOT advised for a patient who is in a long-term relationship with one partner. Certainly
HCV is in blood, and sexual behavior should be considered dangerous where blood may be spread such as when there is a cut
or sore in the genital areas.
Acute Hepatitis C develops approximately
6 to 10 weeks after infection. Patients may experience no symptoms or merely a mild flu-like illness lasting a few days or
weeks and usually without jaundice (yellow skin and eyes). Usually, liver blood tests are not measured and Hepatitis C is
not suspected or diagnosed until years or decades later.
HIV & Hepatitis C
The last
several years, as the overall prognosis of maintained life with aggressive antiviral therapy with respect to HIV has become
a reality, issues surrounding other chronic confections have taken on new interests with the HIV patient. Specific to this is the issue of co infection of the HIV patient with hepatitis C. There is some data to suggest that patient who in fact have HIV and who are co infected with hepatitis
C may have a particularly poor prognosis with respect to liver disease caused by hepatitis C.
Hence, there is increasing interest in the protocol for treating patients with HIV and hepatitis C, with eradication
being its end-point. Essentially, hepatitis C and HIV are very similar viruses,
in that they are both single-strand RNA viruses. They both have worldwide distribution. With respect to hepatitis C, there are six general genotypes that are well described
in the literature. In addition, within genotypes there are sub variations of
genetic makeup, known as quasi-species. In the majority of hepatitis C patients,
infection causes chronic infection of the liver, of which most infections are sub clinical, with respect to symptomatology,
until at a later point when end-stage liver disease develops secondary to cirrhosis.
The rate of viral production is very high for both HIV and hepatitis C.
Globally, approximately 30 to 35 million people are infected
with HIV, and about 170 million people are thought to be infected with hepatitis C, almost six times as many as with HIV. Although hepatitis C has not historically received the recognition that HIV has, both
viruses are significant public health problems worldwide, and of recent, there has been increased recognition in the United
States of the importance of hepatitis C. This is due to a recent announcement
made by the CDC regarding attempts to contact blood recipients from prior to 1990 with respect to the possibility that they
may have been infected with the hepatitis C, and also due to multiple targeted media campaigns, sponsored by both the pharmaceutical
industry and by researchers and healthcare organizations.
Hepatitis C, hepatitis B and HIV may be transmitted by percutaneous
sharp exposure, but hepatitis B and hepatitis C are transmitted much more readily by this route. Hepatitis B and hepatitis C are found with a high prevalence among HIV drug abusers, though likelihood
of infection seems to have increased with time with respect to IV drug abuse. It
is interesting that several studies suggest that at the initiation of an IV drug use habit, infection by either hepatitis
C or hepatitis B tends to occur in the first few months of addiction. In a study
published by Thomas et al. in the Journal of Infectious Disease in 1996,
there is some evidence to suggest that HIV infections may increase the risk of transmission of hepatitis C. As CD-4 counts are shown to decline, hepatitis C viral loads tend to increase dramatically. Perinatal transmission of HIV and hepatitis C virus is greater in co infected women
than in those who have either HIV or hepatitis C virus infection alone. In a
study done by Zanetti et.al.(Lancet. 1995), these researchers compared the likelihood of perinatal transmission of
HCV between women who either were or were not co infected with HIV. Hepatitis
C virus was transmitted to 36% of infants whose mothers were HIV positive but to none of the infants whose mothers were HIV
negative. Similarly, in a study by Hershow et al. in the Journal of Infectious Disease in 1997, HIV-infected women were more likely to transmit the virus perinatally
if they were also infected with hepatitis C virus.
With respect to chronic hepatitis C infection in general, this
tends to be an organ-specific disease in that it causes primarily chronic hepatitis in the majority who are infected with
the virus. In a minority of these patients, chronic infection may lead to cirrhosis,
and certainly in those patients with cirrhosis, there is an increased risk of hepatocellular carcinoma. In addition to organ-specific disease of the liver, hepatitis C has been clearly linked to the development
of mixed cryoglobulinemia, membranoproliferative glomerulonephritis, and porphyria cutanea tarda (PCT). With respect to PCT, recent studies have suggested that approximately 85% of the patients who
have PCT have hepatitis C virus, though the precise relationship between hepatitis C infection and PCT is not exactly known. In general, most patients who get hepatitis C will develop chronic hepatitis C in
that approximately 80% of the patients who are infected with the virus go on to develop some form of chronic infection of
their livers. Of those patients with chronic liver disease, approximately 20%
to 30% will go on to develop cirrhosis, and approximately 80% will have some form of stable chronic disease, causing chronic
inflammation with mild-to-moderate fibrosis.
It is the
patients who develop cirrhosis that are of the greatest concern, since these patients have an increased risk of hepatocellular
carcinoma and may go onto early decompensated liver disease resulting in death
if not provided hepatic transplantation. In fact today, the leading indication
for liver transplantation in the United States is hepatitis C. It has been estimated
that there are approximately 8000 to 10,000 deaths per year attributed to hepatitis C in the United States today. It has been suggested in some modeling by the CDC that medical costs for hepatitis C cost well over 600
million dollars annually and that these costs will only increase over the next several years as patients become more advanced
with respect to their liver disease and transplantation is required. It has been
estimated that approximately 1.8% of the population has hepatitis C in the United, States or approximately 3.9 million people.
( In a city of Jacksonville’s size of 1.1 million people, that would mean approximately 19,800 are presently infected.)
Of these 3.9 million infected Americans, 2.7 are considered chronically infected, and most of these infected patients today
are between the ages of 30 and 50 years of age. In addition, with respect to
active new cases, the actual epidemic has already happened. In fact, the incidence
of new infection has declined in the last several years, especially in the last half decade.
This probably is the result of the ability to now mass screen the blood supply, especially in blood components being
used for transfusion purposes. In addition, all patients undergoing insurance
examinations, most executive physical examinations, and all blood donors are tested for hepatitis C. Hence, this has dramatically increased the awareness of who is already infected with this disease. In addition, there have been several national campaigns, as described above, increasing
the awareness of this infection, highlighting those who are at greatest risk to have this infection, and causing a substantial
increase in the number of patients tested by their primary care physicians in the last several years.
It has been suggested in a study by Dr. Gary Davis, presented
at the 49th Annual Meeting of the American Association for the Study of Liver Disease in 1998, that the percentage
of hepatitis C virus positive patients with cirrhosis will increase from approximately 15.6% in 1998 to approximately 28.9%
by 2018. Of these, the percentage with hepatic decomposition will increase dramatically
as will the number with hepatocellular carcinoma. In addition, liver-related
deaths will increase threefold. Hence, the issue of hepatitis C is real. In general, if one were to develop an algorithm in one’s mind about the outcome
of hepatitis C and were to take 100 patients affected acutely with hepatitis C, approximately 85 would go on to develop some
form of chronic liver disease. Of those, approximately 17, or 20%, would develop
cirrhosis. Of those with cirrhosis, approximately 25% would go on to have decomposition
with early mortality.
Hepatitis C Disease Pathogenesis
With respect to the pathogenesis of hepatitis C infection, this is not completely understood. Infection of hepatocytes by hepatitis C results in cell death, probably as a result of hepatitis C-induced
apoptosis. The cell-mediated immune system may also play a role in the destruction
of hepatocytes, especially as a result of the activity of CD8 and T-helper cells. In
addition, the production of various cytokines in response to hepatitis C virus infection increases the activity of hepatic
stellate cells, the principal producers of the extra cellular matrix. This activation
may occur directly in response to exposure to factors such as Interferon, or it may be an indirect response to the release
of TGF-beta from Kupffer's cells.
Increased activation of hepatic stellate cells results in an increased
production of extra cellular matrix, hence causing new fibrosis. There still
are factors that influence the progression of hepatitis C virus infection. These
include viral load, genotype, and the presence of quasi-species and mode of transmission.
In addition, host-related issues such as age, race, gender and immune response also play a role. In addition, co infection with HIV and hepatitis B, the consumption of alcohol and less geography and smoking
may also play as factors influencing the progression of hepatitis C virus infection.
With respect to HIV, the progression of fibrosis among the patients with hepatitis C virus infection is accelerated
by co infection with HIV. A study by Benhamou et al. in Hepatology in
1999, found that an increase in hepatitis C virus-related fibrosis over time was significantly greater among patients who
were HIV positive than among HIV-negative control. The two groups were matched
with regard to several clinical factors, including age, sex, and alcohol consumption.
These findings suggest that hepatitis C infection behaves as an opportunistic infection with respect to HIV.
In another study Darby et. al. published in Lancet in 1997, the study
looked at 4,865 men and boys in the United Kingdom who had had hemophilia and who were treated with blood products having
a high probability of contamination with hepatitis C virus between 1969 and 1985. Compared
with the general United Kingdom population, patients with hepatitis C virus infection have a 16.7 fold increase in the likelihood
of dying from liver-related causes. However, the incidence of liver-related mortality
among the co-infected patients was increased by a factor of nearly 100, approximately seven times that of patients who are
HIV negative.
In another study published in the Journal of Infectious Disease in 1999 by Lesens et al, the effects
of HIV infection on the progression of liver disease due to hepatitis C was examined in the cohort of patients with hemophilia. A total of 154 hepatitis C virus-positive
patients were studied. 81
patients were also infected with
HIV. More than 25% of patients with progressive liver disease were co infected with HCV and HIV while only approximately 5% were infected with the hepatitis C virus
alone. Risk of occurrence of progressive liver disease in co-infected patients was 7.4. Progressive liver disease developed,
with duration of 17.2 years. The development of progressive liver disease in
these patients was more likely among those with severe AIDS-defining immunodeficiency’s than among patients without
AIDS-defining immunodeficiency. 73% of patients who had AIDS survived for 3.2
years after experiencing progressive liver disease.
Overall, about 40% of patients with HIV infection are co infected with hepatitis C virus. The number of co-infected patients seen by physicians will vary with
the patient population served. The greatest number of co-infected patients are
found in settings where there are large numbers of HIV drug abusers. About 70%
of patients being treated for HIV are on protease inhibitors. A significant number
are also infected with hepatitis C virus, thus increasing the risk for progression of liver disease. Even in the absence of co infection with hepatitis C virus, it is common for patients with HIV to have
liver function abnormalities. Protease inhibitors that are currently used for
the treatment of HIV do not affect the hepatitis C virus. There is no sufficient
homology between the two viruses. The degree of control of HIV replication obtained
using HAART does not affect hepatitis C viral levels. Initiation of HAART can
produce transient elevation of ALT, AST and hepatitis C virus levels. Much of
the hepatotoxicity that is associated with nucleoside analogue drugs is caused by damage to mitochondrial DNA. Replication of mitochondrial and nuclear DNA are regulated by different enzymes. Several nucleoside analogues, most notably FIAU, are inhibitors of DNA polymerase gamma, the mitochondrial DNA polymerase. The disruption of mitochondrial
metabolism causes an accumulation of triglycerides and pyruvates, which in turn causes the development
of lactic acidosis. The drugs, D4T, DDC, and DDI are the most likely to cause
lactic acidosis, although these effects can be produced by any nucleoside analogue.
Underlying liver disease, such as hepatitis B or hepatitis C, can also impair mitochondrial function, and thus patients
who are infected with hepatitis B virus or hepatitis C virus are at risk for added hepatotoxic effects.
In the study published in JAMA this year by Sulkowski, 282 patients were evaluated who were being treated
with new anti-viral treatments were followed prospectively for the appearance of hepatotoxicity assessed by performing serial
ALT determinations during a period of six months. The primary purpose of this
study was to determine whether the risk of hepatotoxicity is comparable for all anti-viral treatment regimens and determines
the impact of hepatitis C virus co infection on anti-viral drug-associated hepatotoxicity.
Of drug studies, ritonavir was associated with a higher incidence of severe hepatotoxicity than any other treatment
regimen examined. Most patients (88%) with hepatitis B virus infection did not
develop severe hepatotoxicity. Among patients prescribed a treatment regiment
that did not include ritonavir, hepatitis C virus infection increased the risk of hepatotoxicity by 3.7-fold. Among patients who received ritonavir, there was no difference in hepatotoxicity between patients with
hepatitis C virus positive and hepatitis C virus negative.
Based on this study, a following approach has been suggested in the management of HAART-associated hepatotoxicity. For mild to moderate increases in serum ALT or AST, the patient should be monitored
and observed closely without change in therapy until the patient becomes symptomatic.
With severe elevation, 3.5-fold increases, all anti-viral medications should be stopped. To continue the use of only one or two the anti-viral medications could lead to increased resistance to
therapy. The physician should also rule out alternative possibilities, such as
hepatitis A and hepatitis B. Liver enzymes will usually decrease over a period
of five to ten weeks with the cessation of anti-viral therapy. When re-starting
HIV medication treatment, consider a non-ritonavir-based regimen.
With respect to patients who have HIV, with respect to hepatitis C, screening for hepatitis C should be mandatory. In addition, patients who have co infection with hepatitis C should not drink alcohol. There is clear evidence that alcohol consumption has synergistic effects on the viral
activity of hepatitis C with respect to its ability to induce progressive liver damage.
Anti-viral medications are well known to cause liver disease as described above.
An aggressive HIV therapy should not be withheld from patients who have hepatitis C, but hepatic effects should be
clearly monitored.
Treatment For HCV
As described above, with the increasing effectiveness of chronic therapy
for patients with HIV and the successful ability to maintain these patients for indefinite periods of time, the clinical and
relevant issues of hepatitis C co infection have become real. Hence, treatment
is now clearly indicated. There are patients, though, for which probably therapy
is more indicated than in others.
In general, all patients with hepatitis C should have a liver biopsy. This
will serve as a good baseline with respect to the effects of hepatitis C that has occurred to the liver. Patients, who have very mild disease, may very well not have aggressive disease, especially if they have
had the virus for some time. On the other hand, patients who have rather advanced
fibrosis and inflammation probably have an advanced form of the disease, either solely as a result of the hepatitis C or secondary
to co-factors such as HIV or long-term alcohol consumption. There is increasing
evidence that the use of long-term maintenance therapy in patients who have hepatitis C with advance fibrosis may retard for
a period of time the progression of the liver to full decompensation and the need for transplantation, and in fact there are
ongoing, long-term clinical trials to prove the efficacy of long-term administration of Interferon in such patients irrespective
of its ability to clear the virus.
At general, in patients who are HIV negative who have hepatitis C, the first primary goal of
therapy with pharmacotherapy is to eradicate the virus. Unfortunately, this goal is often not met. But as described above, the mere presence of some form of long-term pharmacotherapy for the eradication
of hepatitis C, even when met with failure with respect to eradication, may have some long-term benefits with respect to retarding
the virus with its effect of fibrosis and subsequent cirrhosis.
The present gold standard for hepatitis C therapy in patients
who are not HIV positive includes the use of two drugs known as Interferon and ribavirin.
Initially, several years prior, the sole therapy for hepatitis C was monotherapy with Interferon, given for approximately
6 months’ time. With gradual accumulation of data, recommendations from
the national institute of health suggested lengthening this treatment up to 12 to 18 months.
Approximately 3 years ago, the introduction of ribavirin as a form of synergistic pharmacotherapy with Interferon was
suggested and eradication rates were suggested to be significantly improved with this form of combination therapy. In general, Interferon therapy alone for approximately 6 months probably only causes approximately
6% to 8% sustained response. With combination of Interferon and ribavirin, we
can see increased sustained response of between 30% and 40%(McHutchison et al. NEJM 1998). This response can be measurably increased by lengthening the duration of Interferon and ribavirin therapy
such that in most cases, we are treating now patients for approximately 48 weeks.
Patients who seem to respond the best with respect to Interferon- and ribavirin-based therapy are those with genotype
II and III. Unfortunately, the majority of the patients we will see in the United
States have genotype Ia and Ib, which seems to be the least effective with conventional Interferon and ribavirin therapy. In addition, pretreatment viral loads of less than 2 million copies per cubic centimeter
have been suggested to have a better prognosis with respect to long-term Interferon and ribavirin therapy. In addition, the female gender or an age less than 40 has also been suggested to be associated with increased
response to Interferon and ribavirin therapy.
Cirrhotics in general do not do well with respect to Interferon
and ribavirin therapy, but on the other hand, as already described, there is increasing evidence that such patients should
not be discounted from therapy, as long-term Interferon therapy may improve these specific patients with respect to outcomes
and the need for early transplantation. However, this issue still awaits
long-term outcome studies which are presently being undertaken. Historically,
the gold standard for consideration for Interferon therapy with ribavirin in patients with hepatitis C have been in those
patients who have elevations of their ALT. Hepatitis C is a unique viral hepatitis
in that you may see fluctuations from normal to high levels of ALT through the course of serial blood draws. This is not the case, necessarily, with hepatitis B or other forms of chronic hepatitis. Hence, one single normal ALT does not exclude the presence of chronic hepatitis. Early clinical studies suggested that in patients, though, who have persistently normal ALTs and who are
treated with Interferon, there may be actually no improvement with respect to their chronic hepatitis C and potential worsening
of their disease, though this issue is an area of intense investigation, with a large multi-center study presently being undertaken
by Dr. Bruce Bacon of St. Louis University. In this study, he is investigating
in the first large multi-center study the effectiveness of treating patients who have persistently normal ALTs with Interferon
therapy. At present, however, the gold standard is to not treat patients who
have normal ALTs with Interferon. This may be somewhat troublesome in that, if
you biopsy many patients who have normal ALTs persistently, their biopsies may in fact show evidence of chronic hepatitis. As already stated above, the present standard of care is to not treat such patients
with persistently normal ALTs.
In general, Interferon is well tolerated. Early on in its use, there was tremendous concern about the potential relationship between Interferon and
underlying depression and other psychiatric disorders. In fact, we have found
that with close monitoring, even in patients with known documented psychiatric history, a full 48 weeks of pharmacotherapy
can be achieved. In fact, we have advocated the initiation of patients who are
going to be treated with Interferon therapy with some kind of antidepressant; specifically, we have used SSRIs as the principal
form of antidepressant in these patients, usually initiating therapy approximately 2 to 3 weeks prior to the start of Interferon-based
therapy. Interferon may cause the clinical manifestations of underlying thyroid
disease. In addition, it has been reported to manifest underlying diabetes mellitus. In addition, it may have several hematological disturbances. Ribavirin, though, has been more of a concern secondary to its effect of hemolysis. Hence, any patient on ribavirin needs to be closely monitored with serial CBCs, which we usually recommend
every other work for at least the first 3 months of therapy. If hemolysis occurs,
we recommend dose reduction of the ribavirin to an appropriate level, where hemoglobin levels can be maintained in a safe
therapeutic range. There are early studies looking at the effects of antioxidants,
specifically vitamin E, in preventing this effect of hemolysis, though data with respect to vitamin E is still pending. In addition, there is some data that erythropoietin may help with respect to off setting
this hemolysis, though again this is certainly by no means the standard of care at present.
Other areas of active research include the use of IL-10 along with interferon
therapy, since IL-10 is known to have anti-fibrosis activity. There has been
some work looking at the use of IL-2 along with interferon, in addition, there are studies looking at different dosing strategies
with interferon.
In general, for all patients who we treat with hepatitis
C, either HIV or not HIV infected, we recommend drawing a baseline CBC, hepatitis-C PCR RNA with Genotype, electrolytes, liver
function studies, and TSH prior to the initiation of therapy. In addition all
patients with Hepatitis C who do not have immunity to either Hepatitis A and or B we recommend vaccination as per the CDC. With the initiation of therapy thereafter, every 2 weeks we repeat the CBC, liver
function studies and electrolytes, and if we see stabilization of the CBC within acceptable parameters, then we can lengthen
the intervals between lab draws to every 4 weeks after the first 3 months of therapy.
Clearly, amongst clinicians there are variations in these schedules of blood draws, but we have found this protocol
to be the most useful with respect to picking up early hematological concerns in relation to pharmacotherapy. In addition, I have employed a standard of seeing these patients physically every 2 weeks during
the first 3 months of therapy since the effects of Interferon with respect to psychological ,biochemical, and hematological
concerns seems to be most pronounced during the initiation of therapy. Thereafter,
if patients seem to be doing well, every month seems to be a reasonable interval to meet with the patient and review their
labs. We also recommend a full physical examination on each visit, with careful
attention with respect to any clinical complaint that the patient may be having.
Lastly, we have strongly encouraged the use of outside support
groups for patients considering therapy or who are on therapy. The support group
seems to help the patient find fellowship with other sufferers. More importantly,
it allows them a standard to which they can feel comfortable with respect to the magnitude of impact that the therapy has
on their daily lives. We have such a support group here in Jacksonville, and it has been active for the last 3 years.
In conclusion, hepatitis C is a real infection of concern, and
especially now that our HIV patients are living and doing well with antiviral therapy, with the goal that we will eventually
find some form of therapy to cure them of their HIV, it is only appropriate that we treat them for their hepatitis C virus.
Article by Kyle P. Etzkorn, MD, FACP
CHRONIC AUTOIMMUNE HEPATITIS
Chronic autoimmune hepatitis is a condition which predominantly
affects females. It has an 8:1 female to male predominance.
Autoimmune hepatitis can be subcategorized into six primary subtypes. Type 1, also known as lupoid, is the most common. In these
patients, an ANA antibody, which is a serum test, and an SMA, which is another serum test, will be positive. Type 2a predominantly has only antibodies in the serum against liver kidney microsomes, also known as LKM. Type 2b is very uncommon in the United States and is found predominantly in Europe
in patients who have hepatitis C. In these patients with chronic hepatitis C
infection in Europe, approximately 7% of these will have LKM antibody present in their serum.
Interestingly, these patients with hepatitis C and the presence of LKM respond better to antiviral therapy against
their hepatitis C versus therapy directed against the autoimmune portion of their hepatic disease. Type 3 is associated with a positive ANA and SMA. Lastly,
two conditions known as autoimmune cholangiopathy and primary biliary cirrhosis will have a primarily ANA and AMA respectively
positive.
Chronic autoimmune hepatitis, the most common being type 1, again known as lupoid
hepatitis, was first described in 1950 by Waldenstrom. This is a disease that
primarily affects young people, primarily women. The exact etiology is unknown. There appear to be defects in suppressor T-cells.
This results in the production of autoantibodies against hepatocyte surface antigens.
It is not known whether this is an acquired or primary dysregulation of the immune system.
The injury in type 1 autoimmune hepatitis can vary from severe chronic hepatitis to near
normal activity of the liver. Under the microscope, large lymphocytes and plasma
cells are noted to be infiltrating the liver cells. This condition tends to clinically
present in young women, but there seems to be a bimodal presentation in that the next group of patients mostly diagnosed are
in their fourth and sixth decades of life. The clinical symptoms tend to be insidious
with general malaise, which may progress to outright jaundice, or yellowing of the skin and eyes. Classic treatment is with the initiation of steroids. This
may take up to two years of treatment. Confirmation of a “cure” is
continuous assessment of liver function studies while on a course of prednisone, along with a liver biopsy to confirm resolution
of the hepatitis. Many patients, though, will not respond to prednisone alone
and they require other medications, specifically, azathioprine.
For more information on autoimmune hepatitis, please consult your Borland-Groover
Clinic physician.
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