Friday, October 1, 2010

Hepatitis


Hepatitis

Hepatitis (plural Hepatitides) implies injury to liver characterized by presence of inflammatory cells in the liver tissue. Etymologically the word hepatitis is derived from ancient Greek Hepar or heat meaning liver and suffix –itis denoting   ‘inflammation’. The condition can be self-limiting (healing on its own), or can progress to scaring of liver. 
Acute hepatitis is when it lasts less than 6 months and chronic hepatitis is when it persists longer. A group of viruses known as the hepatitis viruses cause most liver damages worldwide. Hepatitis can also be due to toxins (notably alcohol), other infections or from autoimmune process. It may run a sub-clinical course when affected person may not feel ill. Patient becomes unwell and symptomatic when the disease impairs liver functions that include among other things, screening of harmful substances, regulation of blood composition and production of bile to help digestion
What we can do to reduce the risk of hepatitis?
Vaccines are only available for hepatitis A and B viruses and complete cure is not achieved even with best treatment in many cases. Therefore, more attention should be directed towards prevention. Following steps can reduce the spread of hepatitis.
  • Vaccines every new born child against HBV as per EPI schedule of the government of Pakistan
  • Avoid the use of contaminated water ,unwashed and unpeeled fruits and vegetable etc, as they can be a source  of HAV and HEV
  • Keep all utensils covered and clean to avoid contaminated by files.
  • Adopt good personal hygienic measure e.g. washing of hands thoroughly before eating and after toilet use.
  • All the workers of food industry must be monitored on regular basis for the carrier states of Hepatitis A and E.
  • Blood and blood products must always be adequately screened before transfusion.
  • Strongly discourage the sharing of needles, syringes and shaving accessories.
  • Practice safe sex and spread awareness in public about the dangers of unprotected sex.
  • Women who are infected with hepatitis B or C must undertake adequate contraceptive measures.
  • Early recognition and treatment may prevent long-term complications of hepatitis and reduce morbidity due to this disease.
  • Public awareness programs must be put in place to educate general public about clinical features, mode of spread, prevention and treatment of different types of hepatitis.
Types:
Most cases of acute hepatitis are due to viral infections:
  • Hepatitis A
  • Hepatitis B
  • Hepatitis C
  • Hepatitis B with D
  • Hepatitis E
  • Hepatitis F (discredited)
  • Hepatitis G
Hepatitis A
Hepatitis A or infectious jaundice is caused by a picornavirus. The oro-fecal route, transmitted to human through methods such as contaminated food, transmits it. The patient’s immune system makes antibodies against hepatitis A that confer immunity against future infection .people with hepatitis A are advised to rest, stay hydrated and avoid alcohol. A vaccine is available that will prevent infection from Hepatitis A for life. Hepatitis A can be spread through personal contact; consumption of raw seafood or drinking contaminated water. This occurs primarily in third world countries, infected people excrete the Hepatitis A virus with their stool two weeks before and one week after the appearance of jaundice. This time between the infection and the start of the illness can run from 15 to 45 days, and approximately 15% of suffers may experience relapsing symptoms from 6 months to a year following initial diagnosis.
Hepatitis B
Hepatitis B is caused by a hepadnavirus (A DNA virus, aka Dane particle), which can cause both acute and chronic Hepatitis. Identified method of transmission include blood (Blood transfusion, now rare), tattoos (amateur and professionally done), sexually (through sexual inter course and through contact with blood are bodily fluids), or utero from mother to her unborn child (as the virus can cross the placenta). Blood contact and occur by sharing syringes intravenous drug abuse, shaving accessories such as razor blades, or touching bounds of infected persons. In the United States, 95 % of patients clear their infection and develop anti bodies against Hepatitis B virus. 5% of patients do not clear the infection and develop chronic infection: Only these people are at risk of long terms complication of Hepatitis B which include fulminant hepatic failure, cirrhosis and hepatocellular carcinoma, among others.
Hepatitis C
Hepatitis C (originally “non-A non-B Hepatitis”) is caused by a flavivirus. It can be transmitted through contact with blood as well as through sexual contact. Hepatitis C may lead to a chronic form of Hepatitis, although in January 2007, Researchers at the University Washington announced a breakthrough, which they predict, will lead to a vaccine within five years. {2} Patient with Hepatitis C prone to severe Hepatitis if they contract either Hepatitis A or B, so all Hepatitis C patients should immunized against Hepatitis A & Hepatitis B if they are not already immune. The genotype of the virus determines the rate of response to treatment. Genotype 1 is more resistant to interferon therapy than other HCV genotype.  The cellular receptors for the virus are CD81 and SR-B1 with claudin-1 as a co-receptor required for a later-step in entry.
Hepatitis E
Hepatitis E produces symptoms similar to Hepatitis A, although which can take a fulminant course in some patients, particularly pregnant woman: it is more prevalent in the Indian sub-continent.
Hepatitis G
Another type of Hepatitis, Hepatitis G, has been identified, and is probably spread by blood and sexual contact. There is, however, doubt about whether it causes Hepatitis, or is just associated in Hepatitis, as it does not appear to be primarily replicated in the liver.
Drug induced hepatitis.
A large number of drugs can cause Hepatitis. The anti-diabetic drug Troglitazon was withdrawn in 2000 for causing Hepatitis. Other drugs associated with Hepatitis:
  • Allopurinol.
  • Amitriptyline (antidepressant).
  • Amiodarone (anti-arrhythmic).
  • Azathioprine.
  • Halothane (anesthetic gas).
  • Hormonal contraceptives.
  • Ibuprofen and indomethacin (NSAIDs).
  • Ketoconazole (antifungal).
  • Methylbopa (antihypertensive).
  • Minocycline (tetracycline antibiotic).
  • Nifedipine (antihypertensive).
  • Nitrofurantioin (antibiotic).
  • Phenytoin and valproic acid (antiepileptics).
  • Zidovudine (antiretroviral i.e. against AIDS).
  • Some herbs and nutritional supplements.
  • Isoniazid (INH), rifampicin, and pyrazinamide
Treatment
Drug therapies
The standard of care for hepatitis C treatment is weekly injunctions of a drug called pegylated interferon Alfa combined with twice-daily oral doses of ribvirin (rebetol) – a broad- spectrum antiviral agent. Two pegylated interferon medications are available, pig interferon alfa-2b (Pig-intron) and pig interferon Alfa 2a (pegasys).
The goal HCV treatment is to clear the virus from your blood stream. Combined pegylated interferon and ribavirin clear HCV infection in up to half of the people 1—the most common genotype found in the U.S—and in up to 80% of those with genotype 2 and 3.
If you have genotype 1 HCV, your doctor may recommend a course of relatively high dose medications for 48 weeks. If you have genotype 2 or 3, a 24 week course of medication at the lower dose may be adequate.
If one course of combined Pegylated interferon and Ribavirin does not clear HCV from your bloodstream, your doctor may recommend a second course of combination therapy. If your viral load declined during the first round of medication, a second round may clear the virus completely. Even if there was no change in your viral load during the first course of treatment, a second course may help reduce the damage HCV does to your liver.
Guidelines from NIH: indication of Inteferon therapy
  • A positive test result indicating hepatitis A diagnosis of HCV does not necessarily mean you need treatment. The national institute of Health recommends treatment for HCV if you have
  • C virus circulating in bloodstream
  • A biopsy that indicate significant liver damage
  • Elevated levels of liver enzyme called alanine amminotransferase (ALT) in blood
Side effect of medication
Side effects from interferon include serve flu like symptoms, irritability, depression, concentration and memory problem and insomnia. Ribavirin can cause a low red blood cell count (anemia), gout and birth defect. Both drugs can cause skin irritation and extreme fatigue. A small number of people taking combined pegylated interferon and ribavirin may experience psychosis or suicidal behavior.
Side effect from combine pegylated interferon and ribivirin are generally most serve during the first week of treatment, and may be improved with pain relief medications and antidepressant. However, some people taking interferon need their dosage reduce because of severe side effect, and others must stop treatment altogether.
Contra-indication of interferon therapy
  • Uncontrolled major depression
  • Untreated thyroid diseases
  • Very low blood cell count
  • Autoimmune disease
  • Compulsive alcohol abuse
  • Compulsive drug abuse

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