The liver is the body’s largest internal organ. It performs many important jobs, including: Changing food into energy, Cleaning alcohol and poisons from the blood, Making bile that helps with digestion, Producing proteins and blood-clotting factors that the body needs, Regulating glucose in the blood and stores extra sugar, Working with the stomach and intestines to digest food, Storing vitamins and minerals, Removing toxic substances from the blood.
Hepatitis swells the liver, stopping it from working well. It can lead to scarring (cirrhosis) or cancer. Viruses cause most cases of hepatitis. Drug or alcohol use can also lead to hepatitis. Sometimes hepatitis goes away by itself. If it does not, it can be treated with drugs. In some cases, hepatitis lasts a lifetime.
Hepatitis: Acute or Chronic? Acute hepatitis is the initial infection, which may be mild or severe. If the infection lasts for six months or longer, the condition is called chronic hepatitis.
Hepatitis viruses A and E do not cause chronic hepatitis. Hepatitis viruses B, C, and D can produce both acute and chronic episodes of the illness. Chronic hepatitis B and C are especially serious.
Symptoms of viral hepatitis: Symptoms of acute viral hepatitis include fatigue, flu-like symptoms, dark urine, light-colored stools, fever, and jaundice; however, acute viral hepatitis may occur with minimal symptoms that go unrecognized. Rarely, acute viral hepatitis causes fulminant hepatic failure. The symptoms of chronic viral hepatitis often are mild and non-specific, and the diagnosis of chronic hepatitis is often delayed.
Hepatitis types: Currently, five different viruses are known to cause viral hepatitis: A, B, C, D, E.
Hepatitis – A Sometimes called “Infectious hepatitis,”. Causative agent (Hepatitis – A virus, HAV which is a hepato tropic RNA virus classified in the family Picorna viridae. It is relatively resistant outside the body, killed by sun ultraviolet rays and chlorination of water), Reservoir (Cases: Acute, in apparent or mild un icteric, Icteric or post icteric, no chronicity and Carriers: Incubatory in last week of incubation period.), Incubation period (2 – 6 weeks, Average 1 month), Foci of infection (Mainly small intestine with exit in feces. Rarely blood and tissue fluids), Infectivity (Throughout last week of incubation period, pre icteric stage, icteric stage). Ecological features (More in rural areas, More among children, Both sexes are affected More in autumn & early winter).
Mode of transmission: Oral infection mainly through Ingestion infection: ingestion of food or water contaminated by food handler, flies or dust as well as Hand to mouth auto – infection. Parenteral infection is uncommon as the period of viremia is short. It may follow blood transfusion, blood contaminated syringes & needles especially in addicts as well as professional infection of medical care providers.
Clinical picture: In apparent & mild un icteric cases (Influenza like picture, no jaundice), Classical disease (Pre icteric stage with acute onset, fever, headache, malaise, anorexia, liver mild pain and tenderness, dark coca cola colored urine and pale stool, Icteric stage with Jaundice first noticed in sclera & enlarged liver & spleen, and Post icteric stage where Jaundice disappears while hepatomegaly and anorexia Persist for sometimes).
Sequelae: Usually no sequelae & no chronicity. Fulminant hepatitis may occur.
Diagnosis: Clinical diagnosis, Isolation of HAV in cell culture, Serology for hepatitis – A antibodies, Liver function tests.
Prevention: General measures (Environmental sanitation including safe water supply, milk and food sanitation & control of flies, Health education for Importance of food sanitation, personal hygiene and clean habits to avoid oral infection and precautions for blood as using disposable syringes and needles, sterilization of surgical & dental instruments, precautions with blood donors, Immunoglobulin’s should be virus free & sterilized with ultraviolet rays, Precautions on handling blood as using gloves), Specific protection (That includes sero-prophylaxis and vaccination. Sero-prophylaxis: Given to contacts, at risk in outbreaks, pregnant women, travelers. To be given before or shortly after exposure, dose is 0.1 ml. /kg. body wt. I.M.
Vaccination: Hepatitis A vaccine is a killed vaccine given as 2 primary doses & yearly booster dose, it is effective in around 95% of cases and lasts for at least fifteen years and possibly a person’s entire life. If given, two doses are recommended beginning after the age of one. These doses should be given at least 6 months apart. Older children and adolescents can get the vaccine after 23 months. Adults who have not been vaccinated previously and want to be protected against hepatitis A can also get the vaccine).
Control: Case control (Early case finding based on clinical and serological findings, Notification to local health office, Treatment, Disinfection and release: Not before 1 month from onset of disease), Contacts control (Enlistment of contacts, Surveillance & examination for 6 weeks, Seroprophylaxis and Precautions for nursing personnel: Using gloves and Thorough hand washing after nursing, Community control: (Environmental sanitation, Health education campaigns, Seroprophylaxis for at risk groups and Epidemiological studies).
Hepatitis B Also called Serum hepatitis. Hepatitis B spreads from mother to child at birth or soon after, and also through sexual contact, contaminated blood transfusions and needles. Hepatitis B may cause scarring of the liver (cirrhosis) and may lead to liver cancer.
Causative agent: Hepatitis B virus.
Incubation Period (1 – 6 months, Average 3 months). Reservoir of infection (Man, Cases: acute and 5% become chronic for years or lifelong and Carriers: incubatory, convalescent & healthy, no contact carrier. Roughly 95 percent of people who become infected with the hepatitis B virus clear the virus, though they may become very ill. The other 5 percent become chronic carriers of the disease. They are often not ill when they acquired it and may otherwise be unaware of the infection until it does substantial damage (including that which leads to liver cancer), Foci of infection (Blood, Tissue fluids as semen, vaginal secretions and saliva, Breast milk).
Mode of transmission: Exposure to infected blood (Contaminated syringes &needles as with addicts, Blood or blood products transfusion, Tattooing, Professional infection where skin with abrasion may be contaminated on giving IV. Injection, taking blood sample, dental or surgical manipulation). Other ways of transmission (Using shaving razors & tooth brushes in common, Sexual contact, Congenital infection, Organ transplantation, Renal dialysis, Semen banks, Oral route), Clinical picture (Manifestations are similar to hepatitis – A except Onset is insidious, No or mild fever. There is arthralgia).
Sequelae: Persistence of carrier state and infectivity for years or for life. Sequelae include liver cirrhosis & malignancy, Fulminant hepatitis with high case fatality.
Prevention: General measures (Using disposable syringes & needles. For dental & surgical safety use sterile disposable kits. If not available, sterilize instruments before & after use. Medical personnel must use gloves. Exclude addicts from donating blood. Exclude those who have had hepatitis before from donating blood. Screening blood taken from blood donors and exclude the positives. Avoid sex with known hepatitis cases).
Diagnosis: Clinical findings, Hepatitis markers, Liver function tests. Laboratory significance of HBsAg: The antigen persists in the body for years & stimulate the formation of antibody (HBsAb) which can be used for Screening blood donors for HBsAg and Differentiating hepatitis B from other types of hepatitis.
Specific measures (Vaccination and Sero-prophylaxis).
Hepatitis B Vaccines: Including HBSAg vaccine, Recombinant vaccine. HBSAg plasma derived vaccine: Is prepared from HBSAg plasma + ve and is to be given as 3 doses, the 2nd dose to be given as soon as possible and the 3rd dose to be separated from the 2nd dose by at least 8 weeks. Recombinant vaccine: prepared by genetic engineering on yeast cells. It is the one used in Egypt. Three doses are required, 0.5 ml each, I.M. Ideally the vaccine is to be given as follows: 1st dose ( 20 micrograms) to be given within 24 hours of birth then 2nd dose( 20 micrograms) after 1 month then the 3rd dose (10 micrograms) after 6 months. In Egypt it is given at 2,4,6 months for the sake of coverage. Routine hepatitis B immunization results in more than 95% of people being protected. Infants born to HBV-infected mothers should receive hepatitis B vaccine and hepatitis B immunoglobulin within 12 hours of birth. It is also recommended that health-care workers be vaccinated.
Seo-prophylaxis: Hepatitis B immunoglobulin is recommended for People exposed to blood known or suspected to be infected with hepatitis B virus as by being poked with a used injection needle; being splashed in the mouth, nose or eyes with infected blood; being bitten by someone with hepatitis B; or having contact with household articles such as a toothbrush, dental floss, or a razor contaminated with blood from an infected person, People who have had unprotected sex with a person with hepatitis B, Victims of sexual assault, Newborns and infants less than 12 months of age whose mothers have hepatitis B, Newborns whose mothers are at high risk of infection with hepatitis B, such as injection drug users or sex trade workers.
A dose of hepatitis B vaccine may be given at the same time as hepatitis B immunoglobulin. Two more doses of hepatitis B vaccine may be given later to provide full, long-term protection against infection.
Control: Case finding, Treatment (Hepatitis B drug therapy: Lamivudine, adefovir, entecavir, telbivudine and tenofovir are approved oral antiviral agents. Before the approval of these antiviral agents, interferon, an immune potentiator, had been used to treat chronic hepatitis B infection. Resistance to drug therapy is common).
Hepatitis C Formerly known as “non-A, non-B hepatitis,”. Hepatitis C is the most common form of viral hepatitis. Causative agent (Hepatitis C virus, HCV which is a small RNA virus that is closely related to the flaviviruses and animal pestiviruses), Reservoir (Man, cases and incubatory carriers), Incubation period (The incubation period ranges from 2 weeks to 6 months. It is most commonly 6–9 weeks, after which serum alanine transaminase (ALT) levels rise. Current HCV antibody tests become positive 2–3 months after exposure).
Mode of transmission: Hepatitis C is primarily transmitted by blood-to-blood contact. While it can be transmitted through contaminated blood transfusions and/or needles, for a substantial number of patients, the cause is unknown.
Routes of transmission include Use of non- sterile injecting equipment, Needle stick injury or other parenteral inoculation; this includes blood and blood product transfusions before blood-bank screening, Some household activities, such as sharing razors or toothbrushes (very rare), Invasive procedures with inadequate infection control e.g. dental or medical procedures, tattoos or body piercing, Vertical transmission from mother to neonate, breastfeeding has no additional risk. Rates of sexual transmission of HCV infection are negligible. The risk is increased if the HCV-positive partner is immune compromised, as the viral blood titer may be increased, or when there is the possibility of blood-to-blood contact – for example, sex during menstruation and traumatic sexual practices.
Period of communicability: Communicability is from 1 or more weeks before the onset of symptoms, and during the acute clinical stage of HCV infection. All HCV-positive individuals – that is, people with chronic infection – should be considered potentially infectious, although the risk is minimal in the non viraemic (PCR-negative) individual.
Susceptibility: All non- immune people are susceptible to infection. The degree of immunity following infection is uncertain. If infection resolves and the virus is cleared, the person can be re infected with the same and other genotypes.
Prevalence: Hepatitis C occurs worldwide. Hepatitis C infection is common in about 25 percent of people who are HIV-positive. Hepatitis C also infects up to 90 percent of HIV-infected injection drug users. It is more severe in patients with HIV. Three-quarters of people infected with HCV become chronically infected with the virus. Of these, approximately 10–20 per cent will develop liver cirrhosis and an estimated 5 per cent will develop hepatocellular carcinoma.
A high percentage of people (50–80 per cent) develop a chronic infection. However, if infection resolves and the virus is cleared, the person is not immune and can be re infected.
Clinical picture: More than 90 per cent of infections with HCV are asymptomatic. When symptoms and signs do occur, they are similar to other forms of viral hepatitis, but usually milder. Symptoms include anorexia, abdominal discomfort, nausea, vomiting, lethargy, and occasionally rashes and arthralgia. Jaundice and dark urine may follow.
Diagnosis: HCV infection is confirmed by using the combination of an HCV antibody test and polymerase chain reaction (PCR) to detect HCV RNA. A positive antibody test implies previous infection with the virus, and a positive HCV RNA test implies ongoing infection.
The hepatitis C virus was only discovered in 1989, and testing of blood used for transfusions for hepatitis C has only been done since the 1990s. What this means, is that anyone who had a blood transfusion prior to that time could be at risk, hence the testing recommendations.
Prevention: All healthcare providers with potential contact with blood or body fluids should use standard precautions. Use single-use equipment for all skin-penetration procedures, or use appropriate cleaning, disinfection or sterilization methods when reusable instruments are used for any procedure. This includes needles. There is no vaccine available for the prevention of hepatitis C Post-exposure prophylaxis with immunoglobulin has no role.
Both hepatitis B and hepatitis C can be passed sexually. The consistent use of condoms can greatly reduce risk of contracting not only hepatitis but other sexually transmitted infections, including HIV. Hepatitis C is less likely to be transmitted sexually than hepatitis B, but it is still possible.
Control: Case finding: All people diagnosed with HCV infection should be reviewed by a hepatitis specialist. If it is determined that a person carries hepatitis C, medications are available that can clear the virus in up to 99 percent of people. This means that even if someone is positive, he or she may be able to prevent cirrhosis and reduce risk of liver cancer. Treatment is offered based on the presence of liver fibrosis. Combined therapy with pegylated interferon and ribavirin is a possible treatment regimen. Newer antiviral agents may also be available via clinical trials. Counseling of the patient is a very important part of management.
Hepatitis D Also called delta hepatitis. Is a rare and serious form of hepatitis that most often infects intravenous (IV) drug users who are also carriers of the hepatitis B virus. It is spread only in the presence of the hepatitis B virus and is transmitted in the same ways. Hepatitis D is a serious health problem because it occurs in those with hepatitis B, increasing the severity of symptoms associated with hepatitis B.
Hepatitis E Similar to hepatitis A, hepatitis E is prevalent in countries with poor sanitation.
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