Wednesday, January 21, 2015

A Wearable Patch for Allergy Desensitization

Food allergies can sometimes be so severe that they can lead to anaphylaxis, an allergic reaction in which a person's airway swells, blocking normal breathing. Some food allergies are so severe that exposure to even the tiniest amount can be life-threatening. Peanuts, eggs, milk, fish, shellfish, and wheat are among the most common food allergens.

One way to treat a person with a food allergy is to inject the allergen - at truly miniscule doses at first, and then when the patient's immune system begins to tolerate the allergen, slowly raising the dose. Another is to have the patient eat (ingest) miniscule amounts of the allergen. Both methods must be done under close supervision. If done properly, the patient gradually becomes "desensitized" to the allergen, that is, he/she becomes able to tolerate higher doses of the allergen. Although there is no guarantee that a person's food allergy will go completely away, desensitization can potentially reduce an allergic reaction enough that an allergic reaction is no longer life-threatening. The problem is that these desensitization methods (injection or ingestion) are somewhat risky - there's always the possibility that too big of an immune reaction (anaphylaxis) will be triggered by one of the treatment doses.

But now a French firm may have a better way. DBV Technologies has developed a plastic patch called Viaskin designed to deliver small doses of allergen slowly and directly into the skin. In the skin the allergen is taken up by cells of the lymphatic system and delivered directly to immune cells in lymph nodes, where the immune response takes place. Because the allergen never enters the bloodstream, the risk of anaphylaxis is reduced.

Initial clinical trials to test the safety and effectiveness of Viaskin using peanut allergen are encouraging. It is likely to be several years before Viaskin is available (more clinical trials are planned), but the company is so confident that it is already working on Viaskin products for milk allergies and for allergies to house dust and mites.

Tuesday, January 13, 2015

Screening for Lung Cancer

Testing individuals who appear to be healthy for signs of a particular disease is called screening. The hope is to find the disease before it has caused undue harm and while it can still be treated. But when the disease is not common or the screening test is expensive, it's simply not cost effective to screen everyone. That's why epidemiologists and health professionals try to develop screening guidelines that focus sub-populations of the population that are at the highest risk. By screening only those most likely to have or get the disease or condition, expensive screening tests DO become cost-effective, at least for that specific group.

So, how about screening for lung cancer? The best test for detecting lung tumors while they are still small enough to be treated is low-dose computed tomography (LDCT). The test is expensive, so screening everyone just isn't practical. That's where the U.S. Preventive Services Task Force USPSTF comes in. The task force is charged with determining which screening tests should be made available to whom, based on a risk/benefit analysis. In 2014 the USPSTF revised their screening recommendations for lung cancer. Under the new guidelines, annual LDCT screening for lung cancer is now recommended for all persons aged 55-80 who have a 30 pack-year history and who are still smoking or have quit within the past 15 years. In 2008, over 7 million U.S. adults were 30- pack-year smokers! Screening all smokers in this high-risk group every year could save more than 20,000 lives per year.

For your information, "pack-years" is the product of packs smoked per day times years smoked. A thirty pack-year smoker has smoked at least a pack a day for 30 years, or two packs a day for 15 years, or three packs a day for 10 get the idea. If you're not a 30 pack-year smoker you aren't eligible for this screening, meaning that your medical insurance probably won't pay for it.

Monday, January 12, 2015

Bone Broth: The Latest Trendy Drink

Are you a believer in the health benefits of bone broth? Do you make it from scratch in your own home, or sip it in a trendy boutique? Seriously? You need to read two articles: A feature article in the New York Times, and a rebuttal article in the Huffington Post. Together, they'll give you a pretty good sense of the breadth of opinions about bone broth.

Who is right, do you think?

Sunday, January 4, 2015

Current Guidelines for HIV Screening

The USPSTF currently recommends routine screening for HIV infection for all adults between the ages of 15 and 64, all pregnant women, and persons of any age who are "at risk". The current recommendations were last updated in 2013; before that, the USPSTF did not recommend routine screening for HIV.

The Centers for Disease Prevention and Control (CDC) has been recommending routine screening for HIV since 2006, so the fact that the USPSTF ultimately came to the same conclusion (albeit seven years later) shouldn't have been a big surprise. However, the USPSTF's recommendations carry more weight than the CDC's, because under the Affordable Care Act private insurance companies are required to pay for preventive services that the USPSTF recommends with grades of "A" or "B". These recommendations were given a grade "A" level of approval.

Friday, January 2, 2015

Compounding Pharmacy Executives Face Murder Charges

Back in 2012 a compounding pharmacy in New England made some injectable steroid compounds that caused an outbreak of fungal meningitis, ultimately killing 64 people in nine states. At the time, (see this blog Oct. 9, 2012) I pointed out that compounding pharmacies are regulated by state boards of pharmacy, not by the federal government, making it difficult to oversee facilities pharmacies that sell their products across state lines. It wasn't even clear when (or if) anyone would be held accountable.

Well, finally: the United States attorney's office in Massachusetts has just charged 14 people with crimes associated with the event. An owner of the company and the company's head pharmacist were each charged with 25 counts of second-degree murder in seven states; both could receive maximum sentences of life in prison if convicted. According to the indictment, the two knew that the drugs they were producing were not being tested properly for sterility, but they permitted the company to continue producing and shipping the drugs anyway. (Oops!) Twelve other people were charged with various related crimes including mail fraud, conspiracy, and violation of the Food, Drug and Cosmetic act. Some of those charged were pharmacists working at the company.

The company ceased operation and declared bankruptcy after the 64 deaths. But that probably wasn't enough for relatives of the deceased, especially when (according to an FBI press release), several of the owners tried to transfer 33 million in assets to various banks after a court had ordered the company's assets frozen. We'll be watching to see who (if anyone) actually goes to jail.

Monday, December 22, 2014

E-cigarette Use Among Middle and High School Students

The most recent annual survey by the National Institute on Drug Abuse (NIDA) shows that the use of regular cigarettes by middle and high school students continues to trend downward. However, for the first time the NIDA survey includes questions about the use of e-cigarettes, and the results are startling. Already, the use of e-cigarettes among middle- and high-schoolers exceeds the use of regular cigarettes. Among eighth-graders, 8.7% have used e-cigarettes but only have used regular cigarettes. And by the 12th grade, 17% have used e-cigarettes and 13.7% have used regular cigarettes.

This is the first time the annual NIDA survey has included questions about e-cigarettes, so there's no way to determine how quickly e-cigarette use is rising among young people. Within the next year or so (once we have more data) the trend will become clearer.

Health officials and e-cigarette manufacturers couldn't be farther apart on their goals for e-cigarettes. Health officials would like to see e-cigarettes used only as a useful tool to help current smokers quit smoking. Their chief concern is that e-cigarettes may encourage a whole new generation of young people to smoke who might otherwise never have smoked. E-cigarette manufacturers, on other hand, stand to reap huge profits from the much larger youth market. My guess is that the e-cigarette manufacturers are secretly pleased by the latest statistics, though I don't expect them to say so.

Although e-cigarettes are considered to be relatively safe, they do contain nicotine, an addictive drug. It will be interesting to see how (or if) the federal government or the states choose to regulate e-cigarette use in the future.

Wednesday, December 17, 2014

The FDA Approves a New Version of Gardasil

The FDA has approved a "new and improved" version of Gardasil, the controversial vaccine against Human Papillomavirus (HPV), the group of viruses that cause cervical cancer. The original Gardasil was effective against four types of HPV. The new version, called "Gardasil 9", is effective against those four types of HPV plus five more, for a total of nine.

Gardasil 9 is approved for use in both males and females. In males it is approved for prevention of anal cancer, and coincidentally it would also be effective in preventing the spread of HPV to females. Like the original Gardasil, Gardasil 9 is administered as a series of three shots.

Gardasil remains a controversial vaccine. Some people think that vaccinating young girls against a sexually transmitted virus will lead to promiscuity, even though the available suggests otherwise (see this Blog Oct. 21, 2012). There's also a rumor going around that Gardasil has caused the deaths of dozens of young women; that's not true, either, according to a leading rumor-checking site. The CDC, which collects reports of "adverse effects" on all drugs, continues to stress that Gardasil is safe.