Hepatitis C
Disease Details
Family Health Simplified
- Description
- Hepatitis C is a liver infection caused by the hepatitis C virus, leading to inflammation and potentially severe liver damage if untreated.
- Type
- Hepatitis C is a viral infection that primarily affects the liver. It is caused by the Hepatitis C Virus (HCV). The type of genetic transmission for hepatitis C is not hereditary; instead, the virus is transmitted through contact with infected blood, commonly through sharing needles, blood transfusions (especially before 1992), or from mother to baby during childbirth.
- Signs And Symptoms
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**Hepatitis C: Signs and Symptoms**
Hepatitis C is a liver infection caused by the Hepatitis C virus (HCV). Many people with the infection may not exhibit symptoms, especially in the early stages. However, when symptoms do appear, they might include:
- **Jaundice:** Yellowing of the skin and eyes.
- **Fatigue:** Persistent tiredness and weakness.
- **Dark urine:** Urine may appear darker than usual.
- **Pale stools:** Stools that are lighter in color.
- **Abdominal pain:** Discomfort or pain in the upper right side of the abdomen.
- **Loss of appetite:** Reduced desire to eat.
- **Nausea and vomiting:** Feeling sick to the stomach and possible vomiting.
- **Joint pain:** Pain in the joints, often described as aches.
In chronic cases, additional signs and symptoms may develop as liver damage progresses, including:
- **Weight loss:** Unexplained loss of weight.
- **Itchy skin:** Persistent itching.
- **Swollen abdomen:** Fluid accumulation (ascites) leading to a swollen belly.
- **Swelling in the legs:** Fluid retention causing leg swelling.
- **Easy bruising or bleeding:** Increased tendency to bruise or bleed.
Regular medical check-ups and blood tests are essential for those at risk to detect and manage Hepatitis C early. - Prognosis
- The responses to treatment is measured by sustained viral response (SVR), defined as the absence of detectable RNA of the hepatitis C virus in blood serum for at least 24 weeks after discontinuing treatment, and rapid virological response (RVR), defined as undetectable levels achieved within four weeks of treatment. Successful treatment decreases the future risk of hepatocellular carcinoma by 75%.Prior to 2012, sustained response occurred in about 40–50% of those with HCV genotype 1 who received 48 weeks of treatment. A sustained response was seen in 70–80% of people with HCV genotypes 2 and 3 following 24 weeks of treatment. A sustained response occurs for about 65% of those with genotype 4 after 48 weeks of treatment. For those with HCV genotype 6, a 48-week treatment protocol of pegylated interferon and ribavirin results in a higher rate of sustained responses than for genotype 1 (86% vs. 52%). Further studies are needed to determine results for shorter 24-week treatments and for those given at lower dosages.
- Onset
- Hepatitis C is a liver infection caused by the hepatitis C virus (HCV). It often has a stealthy onset, with many people not experiencing noticeable symptoms until significant liver damage has occurred. Acute hepatitis C may manifest within 2 weeks to 6 months after exposure, but chronic hepatitis C typically develops over many years. It can lead to long-term complications like liver cirrhosis and liver cancer.
- Prevalence
- The prevalence of Hepatitis C varies globally. According to recent estimates, around 58 million people worldwide are living with chronic Hepatitis C infection. The prevalence is particularly high in regions such as Central and East Asia, North Africa, and the Middle East. Effective screening and treatment programs can help manage and reduce the prevalence of this disease.
- Epidemiology
- The World Health Organization estimated in a 2021 report that 58 million people globally were living with chronic hepatitis C as of 2019. About 1.5 million people are infected per year, and about 290,000 people die yearly from hepatitis C–related diseases, mainly from liver cancer and cirrhosis.Hepatitis C infection rates increased substantially in the 20th century due to a combination of intravenous drug abuse and the reuse of poorly sterilized medical equipment. However, advancements in treatment have led to notable declines in chronic infections and deaths from the virus. As a result, the number of chronic patients receiving treatment worldwide has grown from about 950,000 in 2015 to 9.4 million in 2019. During the same period, hepatitis C deaths declined from about 400,000 to 290,000.Previously, a 2013 study found high infection rates (>3.5% population infected) in Central and East Asia, North Africa and the Middle East, intermediate infection rates (1.5–3.5%) in South and Southeast Asia, sub-Saharan Africa, Andean, Central and Southern Latin America, Caribbean, Oceania, Australasia and Central, Eastern and Western Europe; and low infection rates (<1.5%) in Asia-Pacific, Tropical Latin America and North America.Among those chronically infected, the risk of cirrhosis after 20 years varies between studies but has been estimated at ~10–15% for men and ~1–5% for women. The reason for this difference is not known. Once cirrhosis is established, the rate of developing hepatocellular carcinoma is ~1–4% per year. Rates of new infections have decreased in the Western world since the 1990s due to improved screening of blood before transfusion.In Egypt, following Egypt's 2030 Vision, the country managed to bring down the infection rates of hepatitis C from 22% in 2011 to just 2% in 2021. It was believed that the high prevalence in Egypt was linked to a discontinued mass-treatment campaign for schistosomiasis, using improperly sterilized glass syringes.In the United States, about 2% of people have chronic hepatitis C. In 2014, an estimated 30,500 new acute hepatitis C cases occurred (0.7 per 100,000 population), an increase from 2010 to 2012. The number of deaths from hepatitis C has increased to 15,800 in 2008 having overtaken HIV/AIDS as a cause of death in the US in 2007. In 2014, it was the single greatest cause of infectious death in the United States. This mortality rate is expected to increase, as those infected by transfusion before HCV testing become apparent. In Europe, the percentage of people with chronic infections has been estimated to be between 0.13 and 3.26%.In the United Kingdom, about 118,000 people were chronically infected in 2019. About half of people using a needle exchange in London in 2017–18 tested positive for hepatitis C of which half were unaware that they had it. As part of a bid to eradicate hepatitis C by 2025, NHS England conducted a large procurement exercise in 2019. Merck Sharp & Dohme, Gilead Sciences, and Abbvie were awarded contracts, which, together, are worth up to £1 billion over five years.The total number of people with this infection is higher in some countries in Africa and Asia. Countries with particularly high rates of infection include Pakistan (4.8%) and China (3.2%).Since 2014, extremely effective treatments have been available to eradicate the disease within 8–12 weeks in most people. In 2015, about 950,000 people were treated while 1.7 million new infections occurred, meaning that overall the number of people with HCV increased. These numbers differ by country and improved in 2016, with some countries achieving higher cure rates than new infection rates (mostly high income countries). By 2018, twelve countries are on track to achieve HCV elimination. While antiviral agents will curb new infections, it is less clear whether they impact overall deaths and morbidity. Furthermore, for them to be effective, people need to be aware of their infection – it is estimated that worldwide only 20% of infected people are aware of their infection (in the US, fewer than half were aware).
- Intractability
- Hepatitis C is not considered intractable. It is a viral infection that can lead to significant liver damage, but with advancements in antiviral treatments, many people can achieve a sustained virologic response (SVR) which is effectively a cure. Modern direct-acting antiviral (DAA) medications have high cure rates, often exceeding 90%. Early detection and treatment are key to preventing severe complications.
- Disease Severity
- Hepatitis C is a liver infection caused by the hepatitis C virus (HCV). Severity can vary greatly among individuals. Some people may experience only a mild, acute illness, while others may develop chronic hepatitis C, which can lead to serious complications. Chronic hepatitis C can result in long-term health issues, including liver fibrosis (scarring), cirrhosis (severe scarring), liver failure, and hepatocellular carcinoma (liver cancer). The severity of the disease often depends on factors such as the duration of the infection, coexisting medical conditions, and lifestyle factors like alcohol consumption. Early diagnosis and appropriate treatment can significantly improve outcomes.
- Healthcare Professionals
- Disease Ontology ID - DOID:1883
- Pathophysiology
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Hepatitis C is a viral infection caused by the hepatitis C virus (HCV), which primarily affects the liver. The pathophysiology of hepatitis C involves several stages:
1. **Viral Entry and Replication**: HCV enters the liver cells (hepatocytes) by binding to specific receptors on the cell surface. Once inside, it releases its RNA genome, which is then replicated and translated into viral proteins by the host's cellular machinery.
2. **Immune Response and Inflammation**: The presence of HCV triggers the immune system to respond. This response includes the activation of various immune cells like T cells and the release of cytokines, leading to inflammation. However, the immune system often fails to completely eradicate the virus, resulting in persistent infection.
3. **Liver Damage**: Chronic inflammation due to the immune response leads to liver cell injury and death. Over time, the continuous cycle of liver cell damage and repair can cause the development of fibrosis, where scar tissue replaces normal liver tissue. As fibrosis progresses, it may lead to cirrhosis, characterized by extensive scarring and impaired liver function.
4. **Complications**: Advanced liver disease due to hepatitis C can result in severe complications, including liver failure, portal hypertension (increased blood pressure in the portal vein), and an increased risk of hepatocellular carcinoma (liver cancer).
Effective antiviral therapies can clear the virus from the body, reducing or eliminating the risk of these long-term complications. - Carrier Status
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For hepatitis C:
**Carrier Status:** Hepatitis C can result in a chronic infection where the virus persists in the body. Some individuals may have no symptoms but can still transmit the virus to others, effectively being carriers.
**NaN:** "NaN" is a term often used in computing to denote "Not a Number" or missing/undefined data. It isn't applicable in a medical context for hepatitis C unless referring to data errors or missing information in medical records or research data. - Mechanism
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Hepatitis C is caused by the Hepatitis C virus (HCV), which primarily affects the liver. Here's a brief overview of its mechanism and molecular mechanisms:
### Mechanism:
1. **Entry into Host Cells**: HCV primarily targets liver cells (hepatocytes). The virus binds to specific receptors on the surface of the hepatocyte, such as CD81 and the scavenger receptor class B type I (SR-BI), leading to endocytosis of the virus.
2. **Replication**: Once inside the cell, HCV releases its RNA genome into the cytoplasm. This RNA serves as a template for both translation and replication. The viral RNA is translated into a single polyprotein, which is then cleaved by host and viral proteases into individual functional proteins.
3. **Viral Assembly and Release**: Newly synthesized viral RNA and proteins are assembled into new virus particles within the endoplasmic reticulum. These particles are then transported to the Golgi apparatus and ultimately released from the cell to infect new hepatocytes.
### Molecular Mechanisms:
1. **RNA Genome**: HCV has a positive-sense single-stranded RNA genome, approximately 9.6 kb in length. The RNA contains an internal ribosome entry site (IRES) at the 5' untranslated region (UTR) which facilitates the translation of the viral polyprotein.
2. **Polyprotein Processing**: The polyprotein is processed into structural (Core, E1, E2, p7) and non-structural (NS2, NS3, NS4A, NS4B, NS5A, NS5B) proteins. Host signal peptidases and viral proteases such as NS3-4A are involved in this cleavage process.
3. **Replication Complex**: Non-structural proteins NS3, NS4A, NS4B, NS5A, and NS5B form a membrane-associated replication complex. NS5B is the RNA-dependent RNA polymerase responsible for synthesizing the new RNA genomes. NS5A plays a role in RNA replication as well as in the assembly of new virions.
4. **Host Interactions**: HCV manipulates host cell mechanisms to favor its replication. For instance, NS5A interacts with host cell factors to inhibit apoptosis and modulate immune responses. Additionally, HCV induces changes in lipid metabolism and rearranges intracellular membranes to create a favorable environment for its replication.
These processes allow HCV to persist in the liver, often leading to chronic infection, which can result in liver inflammation, fibrosis, and eventually cirrhosis or hepatocellular carcinoma. - Treatment
- Those with chronic hepatitis C are advised to avoid alcohol and medications that are toxic to the liver. They should also be vaccinated against hepatitis A and hepatitis B due to the increased risk if also infected. Use of acetaminophen is generally considered safe at reduced doses. Nonsteroidal anti-inflammatory drugs (NSAIDs) are not recommended in those with advanced liver disease due to an increased risk of bleeding. Ultrasound surveillance for hepatocellular carcinoma is recommended in those with accompanying cirrhosis. Coffee consumption has been associated with a slower rate of liver scarring in those infected with HCV.
- Compassionate Use Treatment
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For hepatitis C, compassionate use treatments and off-label or experimental therapies may be considered in certain cases, particularly for patients who have not responded to standard treatments or have specific medical conditions that limit available options. Some of these treatments include:
1. **Experimental Direct-Acting Antivirals (DAAs)**: Newer DAAs in clinical trials may be used under compassionate use for patients with limited options.
2. **Adjunctive therapies**: These can include the use of drugs like ribavirin in novel combinations that are not yet standard practice.
3. **Alternative regimens with approved DAAs**: Sometimes, physicians may use different combinations or durations of existing FDA-approved DAAs tailored to patient-specific factors.
4. **Host-targeted therapies**: Experimental drugs targeting host factors rather than the virus, such as cyclophilin inhibitors.
5. **Immunomodulatory therapies**: These include interferon or newer immune-based therapies that are still in experimental stages.
These treatments are typically accessed through clinical trials or special compassionate use programs set up by pharmaceutical companies, and they require close monitoring by healthcare professionals. - Lifestyle Recommendations
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For hepatitis C, here are some lifestyle recommendations:
1. **Avoid Alcohol**: Alcohol can accelerate liver damage. It’s important to stop drinking completely.
2. **Healthy Diet**: Consume a balanced diet rich in fruits, vegetables, lean proteins, and whole grains to support liver health.
3. **Stay Hydrated**: Drink plenty of water to help your liver function properly.
4. **Exercise Regularly**: Engage in regular physical activity to maintain a healthy weight and overall well-being.
5. **Avoid Certain Medications**: Consult with your doctor about over-the-counter medications and supplements that may affect your liver.
6. **Safe Practices**: Avoid sharing needles, razors, toothbrushes, or any items that may have blood on them to prevent the spread of the virus.
7. **Regular Monitoring**: Keep up with regular medical appointments for liver function tests and follow your healthcare provider’s advice.
8. **Avoid Unsafe Tattoos or Piercings**: Ensure these procedures are done in sterile conditions to prevent infections.
9. **Vaccinations**: Get vaccinated against hepatitis A and B if you are not already immune, as co-infections can complicate liver disease.
Following these recommendations can help manage the disease and prevent further liver damage. - Medication
- More than 95% of chronic cases clear with treatment. Treatment with antiviral medication is recommended for all people with proven chronic hepatitis C who are not at high risk of death from other causes. People with the highest complication risk, which is based on the degree of liver scarring, should be treated first. The initial recommended treatment depends on the type of hepatitis C virus, if the person has received previous hepatitis C treatment, and whether the person has cirrhosis. Direct-acting antivirals are the preferred treatment and have been validated by testing for virus particles in patients' blood.
- Repurposable Drugs
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For Hepatitis C, some repurposable drugs include:
1. **Ribavirin**: Initially used for respiratory syncytial virus (RSV), it's part of some combination treatments for Hepatitis C.
2. **Sofosbuvir**: Originally designed for Hepatitis C, it has been considered for repurposing in other viral infections.
3. **Ledipasvir**: Often combined with sofosbuvir, it targets viral proteins and is considered for other RNA viruses.
4. **Velpatasvir**: Used with sofosbuvir, it can potentially treat other viral infections.
These drugs have shown efficacy in different stages or in combination therapies for Hepatitis C and other viral infections. - Metabolites
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Hepatitis C involves alterations in various metabolites due to liver dysfunction. Some key metabolites affected include:
1. **Amino Acids**: Elevated levels of aromatic amino acids (e.g., phenylalanine, tyrosine) and decreased branched-chain amino acids (e.g., valine, leucine, isoleucine).
2. **Bile Acids**: Abnormal bile acid metabolism, often leading to increased serum bile acids.
3. **Lipids**: Dyslipidemia, including altered levels of cholesterol, triglycerides, and phospholipids.
4. **Glucose**: Insulin resistance and altered glucose metabolism.
These metabolic changes reflect the liver’s impaired functional capacity and systemic effects of chronic infection. - Nutraceuticals
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Nutraceuticals refer to products derived from food sources with extra health benefits in addition to the basic nutritional value found in foods. For hepatitis C, several nutraceuticals may offer supportive benefits:
1. **Milk Thistle (Silybum marianum)**: Known for its liver-protecting properties, it may help improve liver function and reduce inflammation.
2. **N-Acetylcysteine (NAC)**: This antioxidant boosts glutathione levels, potentially aiding in liver detoxification.
3. **Turmeric (Curcumin)**: Exhibits anti-inflammatory and antioxidant properties that may help reduce liver inflammation.
4. **Vitamin D**: Chronic hepatitis C patients often have low vitamin D levels, and supplementation may support overall health and improve treatment outcomes.
5. **Omega-3 Fatty Acids**: Found in fish oil, these can help reduce liver fat and inflammation.
Nanotechnology applications (nan) in hepatitis C treatment are an emerging field. Potential uses include:
1. **Targeted Drug Delivery**: Nanoparticles can be engineered to deliver antiviral drugs directly to liver cells, enhancing efficacy and reducing side effects.
2. **Diagnostics**: Nano-based sensors can improve early detection and monitoring of the virus.
3. **Vaccines**: Nanoparticle-based vaccines are being researched to elicit stronger and more targeted immune responses.
While these approaches show promise, they are not substitutes for standard medical treatments and should be discussed with healthcare providers. - Peptides
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Regarding hepatitis C, peptides derived from the virus's proteins, such as the core, envelope, and non-structural proteins (e.g., NS3, NS4, NS5), are often used in diagnostic assays and vaccine development. These peptides can stimulate an immune response and help in the identification of HCV-specific antibodies.
As for nanoparticles (nan), they have significant potential in hepatitis C research and treatment. Nanoparticles can be utilized for targeted drug delivery, improving the efficacy and reducing the side effects of antiviral therapies. They also serve as novel platforms for vaccine delivery, enhancing the immune response by effectively presenting viral antigens to the immune system.