Hepatitis C virus (HCV) is one of the most important causes of chronic liver disease throughout the world. HCV is responsible for approximately 20% of acute hepatitis, chronic hepatitis and 60-70% in almost 30% of the final stages of cirrhosis of liver disease and liver cancer. A major characteristic of acute hepatitis C is a tendency to turn into chronic liver disease. At least 75% of patients with acute hepatitis C eventually develop chronic infection.Evolution
Chronic hepatitis C varies greatly in terms of evolution. On the one hand there are patients who have no signs or symptoms of liver disease and liver enzymes were normal serum (blood). In these cases, biopsy usually some degree of chronic hepatitis, but the degree of damage is low and long-term prognosis is favorable.
On the other hand, there are patients with severe hepatitis C who have symptoms, the hepatitis C virus RNA (HCV RNA) is present in blood levels of liver enzymes in the blood are elevated, these patients eventually developing cirrhosis and end-stage liver disease.
Between these two categories of patients are most of the patients who have few or no symptoms, mild or moderately elevated liver enzymes and an uncertain prognosis. Researchers estimate that at least 20% of patients with chronic hepatitis C develop cirrhosis, the process requiring between 10 and 20 years. After 20-40 years, a smaller percentage of patients with chronic disease develop liver cancer.
Chronic hepatitis C can be evaluated for liver cirrhosis, liver failure and liver cancer. Approximately 20% of patients develop cirrhosis after 10-20 years after the onset of infection. Hepatic impairment due to cirrhosis is the most common indication for liver transplantation. Hepatitis C is likely to be one of the most common causes of liver cancer worldwide. In Italy, Spain and Japan, at least half of liver cancers are directly related to HCV.
People are the most common liver cancer due to HCV are:
- Persons over 40 years;
- Consumers of alcoholic beverages;
- Patients with liver cirrhosis;
- Patients infected with HCV of approximately 20-40 years.
Groups at highest risk of acquiring hepatitis C are:
- People frequently exposed to blood products;
- Health care that can sting with infected needles;
- Intravenous drug users, including those who have used drugs many years ago;
- Infants born to mothers infected with HCV.
People frequently exposed to blood products include:
- Patients with hemophilia (a blood disease that requires repeated transfusions);
- Patients with organ transplants;
- Patients with chronic renal failure (dialysis);
- Cancer patients requiring chemotherapy.
Other groups seem to have a higher relative risk for hepatitis C are:
- People with high risk sexual behavior, multiple partners and sexually transmitted diseases;
- Cocaine abusers, in particular by intranasal, using tools already used by others.
The mode of transmission of hepatitis C
HCV is transmitted primarily through contact with infected blood or blood products. Blood transfusions and needles and syringes from one person to another, without being sterilized or sterilized enough were the most common methods of broadcast-infection with HCV. Currently, intravenous drug use is the most common risk factor for contact infection. However, many patients acquire hepatitis C without any known exposure to infected blood or without intravenous drug use.
Transmission of hepatitis C from mother to fetus
Transmission from a pregnant woman to child is unusual. In most studies, only 5% of infants born to an infected mother, become infected. Disease in newborns is usually mild and asymptomatic. This method of broadcast-risk is slightly higher in pregnant women who are co-infected with HIV. The risk of transmission of infection from mother to fetus increases with the amount of virus in the mother’s blood (ie number of copies of hepatitis C virus in the blood). Infection can be transmitted through breastfeeding.
Sexual transmission of hepatitis C
Sexual transmission of hepatitis C among monogamous partners (with one sexual partner) is unusual. In terms of sexual transmission of HCV are conflicting studies and no conclusions have been drawn yet.
Research monogamous husbands or partners of patients with hepatitis C revealed that less than 5% were infected, and many of them had other risk factors for infection. For this reason, changes in sexual behavior are not considered mandatory in monogamous couples, but using a means of protection is a more cautious approach. Partner testing for HCV antibodies (anti-HCV) is helpful in counseling patients. People with multiple sex partners should be advised to use condoms as a way to protect it while protecting them and contacting hepatitis B and HIV.
Sporadic transmission of hepatitis C
Sporadic transmission, when the source of infection is unknown, is recorded in approximately 10% of patients with acute hepatitis C and in 30% of patients with chronic hepatitis C. These cases refer also to the community contact infections. The virus can be contacted by knives, superficial wounds, injections, dental extractions or other medical procedures.
HCV is a virus of small size (40-60 mm), embedded in the Flaviviridae family. Because the virus mutates rapidly, changes capsule (outer) protein helps to get rid of “attack” the immune system. There are at least six major genotypes and about 50 subtypes of HCV. The different genotypes have different geographic distribution. There are very few differences in disease severity or evolution in patients infected with different genotypes. However, patients infected with genotypes 2 or 3 respond more frequently to treatment with interferon alfa.
HCV genotypes and serotypes
There are 6 known genotypes and more than 50 subtypes of hepatitis C. Knowing the genotype is useful in specifying the epidemiology of hepatitis C. Knowing the genotype or serotype (genotype-specific antibodies) of HCV is helpful in recommending and managing treatment. Patients with genotype 2 or 3 3 or more efficiently respond to therapy with interferon or interferon alfa therapy combining with ribavirin.
Moreover, when using combination therapy, the recommended duration of treatment depends on the genotype. For those infected with genotype 2 or 3 is recommended therapy for 24 weeks, while those with genotype 1 require 48 weeks. For these reasons, detection of genotype is helpful. Once identified genotype is not necessary a new retest. Genotypes can not change in the course of infection.
Signs and Symptoms
Many patients with chronic hepatitis C are completely asymptomatic. When symptoms are present, are usually mild, nonspecific, and intermittent.
- Tenderness or discomfort in the right upper quadrant (under the ribs on the right);
- Inappetence (loss of appetite);
- Muscle pain;
- Joint pain.
Similarly, physical examination may be normal or may reveal liver tenderness or hepatomegaly mild (liver increased in size). Some patients angiomas (red spots some star-shaped) or palmar erythema (hand stained red).
Once a patient develops cirrhosis or severe liver has a pain, signs and symptoms are more obvious.
The patient may present:
- Muscle weakness
- Weight loss;
- Pruritus (itching);
- Fluid retention;
- Increasing the size of the abdomen.
Physical examination of patients with cirrhosis may include:
- Hepatomegaly (enlarged liver in size);
- Splenomegaly (enlarged spleen size);
- Jaundice (yellow skin and scleroticelor, white portion of the eyeball);
- Decreased muscle tone;
- Excoriations (scratches itching caused by jaundice);
- Ascites (fluid collection in the abdominal cavity);
- Various extrahepatic manifestations.
Extrahepatic complications occur in 1-2% of cases of patients with hepatitis C. The most common complication is extrahepatic cryoglobulinemia which is marked by:
- Skin rash, such as purpura, or urticaria vasculitis;
- Muscle pain;
- Joint pain;
- A positive cryoglobulins in the blood;
- A positive rheumatoid factor in the blood;
- Decreased complement levels in the blood.
Treatment algorithm in patients with chronic hepatitis C
- Diagnosis based on elevated aminotransferase levels (liver enzymes) antibodies and HCV RNA in the blood and liver biopsy to confirm the diagnosis.
- Evaluation of therapy and contraindications possibility.
- Hepatitis C virus genotype testing
- Discussing side effects and evolution after treatment.
- Starting therapy with peginterferon one subcutaneous injection once weekly and ribavirin 1000-1200 mg daily orally.
- Assessment of adverse effects, symptoms, blood counts and aminotransferases from 1.2 to 4 weeks after initiation of therapy and then every 4-8 weeks.
- In week 24 of therapy should be assessed HCV RNA and aminotransferase levels. In patients infected with genotypes 2 or 3 stops therapy. In patients with genotype 1 stop therapy if HCV RNA is still positive but continue up to 48 weeks if HCV RNA negative at week 24, making it the retest at the end of therapy.
- After cessation of therapy, aminotransferase levels must be measured at intervals of 2-6 months.
- In patients who responded to therapy, reassessment is done at 6 months after discontinuation.
Algorithm evaluations during therapy with interferon alfa and ribavirin
- Evaluation of blood counts and aminotransferase levels at 1, 2 and weeks after initiation of therapy and then every 4-8 weeks.
- Dosage adjustment of ribavirin by decreasing by 200 mg once appeared if significant anemia (hemoglobin less than 10mg/dl or hematocrit less than 30%).
- Discontinuation of ribavirin if the hemoglobin is less than 8.5 mg / dL or hematocrit less than 26%.
- Measurement by the polymerase chain reaction for HCV RNA levels at 24 weeks of initiating treatment. If HCV RNA is negative and the patient is infected with genotype 1 (1a or 1b) therapy should be continued for 24 weeks.
- The use of contraceptive methods during therapy and 6 months after stopping it.
- Testing by polymerase chain reaction HCV RNA at end of treatment to check the response to therapy or not.
Algorithm evaluation after cessation of therapy
- Evaluation aminotransferases every 2-6 months after cessation of therapy.
- After 6 months should be tested HCV RNA by PCR (polymerase chain reaction). If it is still negative, long-term evolution is excellent. Relapses have been reported rarely in these situations.
Currently, the only means of preventing the occurrence of new cases of chronic hepatitis C are:
- Monitoring of blood tests;
- Precautions in handling blood, blood products, body fluids;
- Informing the public about the activities at risk of infection.
Programs that promote the use of needles interruption by more than one person are promising in terms of decreasing the number of new cases of chronic hepatitis C among intravenous drug users.
There is no vaccine or immunoglobulin products against hepatitis C, but there is hope that in the near future will be revealed.