Hepatitis C strain poses severe threats, but treatment undergoes 'huge advance'
BY Katie Charles THE DAILY CHECKUP
Wednesday, July 20th 2011, 4:00 AM
As the director of outpatient hepatology at Mount Sinai, Dr. Douglas Dieterich treats liver disease and specializes in treating hepatitis B and C. He oversees the care of several thousand patients with hepatitis C a year.
Who's at risk
According to the CDC, almost 2% of the American population have hepatitis C, but half of these people don't know they're infected. "Hepatitis C is an infection of the liver by a hepatitis virus, which can cause liver disease, cirrhosis and liver cancer," says Dieterich. "Hepatitis C is way more common than everybody thinks."The different strains of hepatitis vary in how they are spread. "The C strain is transmitted almost exclusively through blood-to-blood contact, while A is transmitted through contaminated food and water,"says Dieterich. "The most common strain is hepatitis B, which can be transmitted sexually or through blood, and then passes mother to child."Dieterich recommends universal screening for hepatitis C, because many people are infected without the obvious risk factors. "The CDC recommends that every baby boomer born between 1946 and 1966 should be screened for hepatitis C, because they're at especially high risk,"says Dieterich. "We didn't start screening the blood supply for hepatitis C until 1992, so anyone who had a blood transfusion before then is also at risk," he says.
The clear risk factors for hepatitis C are behaviors that expose you to other people's blood. "The risk factors include injecting drugs or even just snorting drugs,"says Dieterich. "But getting any tattoo or body piercing, even earrings at the mall, is also a possible means of exposure, as are manicures and pedicures and bloody sports like boxing and rugby."Among health-care workers, being accidentally stuck by a needle is also a significant risk. Where you are born in the world can put you at a higher risk, too. "As a result of unsafe medical practices, hepatitis C may affect up to 15% of Egyptians and 5% to 30% of Russians,"says Dieterich.
Signs and symptoms
One reason that hepatitis C is so dangerous is that it has a long incubation period, a time when most patients have no idea they're infected. "The point of screening is to catch hepatitis C when it is not causing symptoms,"says Dieterich. "If you catch it early, it's much more easily treated and even cured."Depending on the condition of the liver, there could be 30-40 years before liver disease sets in, or just two to three years.
Hepatitis C usually starts showing symptoms only when it has damaged the liver enough to cause liver failure. "The symptoms are pretty severe: swelling of the abdomen, swelling of the feet, yellow eyes and jaundice, blood clotting disorders and liver cancer,"says Dieterich. "Unfortunately, it's often too late to treat hepatitis C by the time it becomes symptomatic."The goal of screening is to catch hepatitis C early enough to cure it and prevent patients from suffering these debilitating symptoms.
Traditional treatment
For the past 13 years, doctors relied on a therapy that paired interferon injections with ribavirin pills. "We were able to get about a 40% cure rate with that combination therapy,"says Dieterich. "But as of May 2011, we've had a huge advance.
The FDA has approved two new drugs that allow us to approach 80% cure rates."The latest-generation drugs, telaprevir and boceprevir (brand names Incivek and Victrelis), are both protease inhibitors. "As the virus starts to produce viral proteins, the proteins have to be broken off to be assembled — like taking the plastic wrap off a model airplane,"says Dieterich. "The protease is the enzyme that takes off the wrapping. If it can't do that, the virus can't reassemble."Both drugs are taken in pill form three times a day, on top of the ribavirin pills and interferon injections. "The other good news about the new drugs is that they shorten the time of treatment,"says Dieterich. "If you have genotype 1, like 80% of hepatitis C patients, the standard treatment was 48 weeks. The new drugs can cut that to 24 in over half the cases."Side effects for telaprevir include rash, nausea and diarrhea, and boceprevir can cause anemia and a bad taste in the mouth. "If you respond well to these new drugs, you can stop at 24 weeks and be cured for life,"says Dieterich.
Research breakthroughs
Doctors are confident that the treatment of hepatitis C is undergoing a revolution. "This is the beginning of the new era of direct-acting antivirals (DAAs), of which there are more than 30 undergoing clinical trials,"says Dieterich. Some of these drugs would eliminate interferon — and its side effects — altogether. "I like to think that it's the beginning of the end for hepatitis C,"says Dieterich. "It's like HIV in 1996, except that we can cure it."
Questions for your doctor
If you've been diagnosed with hepatitis C, a key question to ask is, "What genotype do I have?"The genotype determines the length of treatment. A good follow up is, "Will you screen me to rule out liver cancer?"Hepatitis C is a leading cause of liver cancer, so your doctor should order an ultrasound, cat scan or MRI of the liver to check. Another thing to ask is, "Do you think I need to be treated now?"In some cases, it may be appropriate to wait a short period of time, though the rule of thumb for therapy is the sooner the better.
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