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Author: Stephen J. Klemawesch, MD

Celiac disease needs two genes and virus to switch on

Celiac disease needs two genes and virus to switch on

It has been known for some time that two HLA genes (DQ2, DQ8) predispose to celiac disease. What was recently discovered, and reported in The New England Journal of Medicine, is that is seems to take a virus to activate these genes that leads to the disease.  The research focused on the interplay between viruses and genes causing celiac disease, with its gluten sensitivity. The genes alone don’t cause celiac disease.

The virus that appears to be the culprit is a Reovirus that infects the intestines, but is otherwise innocuous, in that is doesn’t cause any symptoms or illness. But in people who inherited HLA-DQ2 or DQ8, the genes are “switched on” and the auto-immune gluten sensitivity develops.

This is very compelling research because development of a viral vaccine could prevent millions of cases of celiac disease.

Mighty mites proven peskier

Mighty mites proven peskier

Dust mites have long been known as the No. 1 cause for allergic asthma around the world. They are the “perfect respirable particle” – at only seven microns in size – and thus, easily inhaled into the lungs.

Based on this information it has long been assumed that the development of dust-mite allergy must occur via breathing in the particles.

Well, new research at the Pasteur Institute in Paris has found otherwise. It seems that the early development of dust-mite sensitivity occurs through the skin. This finding helps explain why many infants have eczema caused by dust-mite allergy, and then later develop allergic asthma.

The researchers in Paris found that dust mites are able to initiate this allergic immune response even in children with normal intact skin. Of course, once eczema develops, there is more ready penetration of the skin layers.

Based on this research it seems reasonable to work harder to minimize dust-mite exposure to infants. Good moves: use mite-barrier sheets, avoid stuffed animals and frequently wash sheets.

Pets in home: many allergy studies, mixed results

Pets in home: many allergy studies, mixed results

By Sasha Klemawesch, MD

Finally, scientific proof of dogs’ superiority! Research studies have reported a variety of health benefits provided to owners by their dogs; perhaps most pertinent to this newsletter being those related to allergies.

A trio of studies in 2003, ’04 and ‘05 in various allergy journals (Current Opinions in Allergy and Clinical Immunology, Journal of Allergy and Clinical Immunology, and Current Allergy Asthma Reports) all reported that children who had dogs in their homes as infants were less likely to develop a variety of allergic maladies, including atopic dermatitis and wheezing, compared with pet-free households.

Many doctors will tell you the key core foundations of good health are regular exercise and a balanced diet. Now dogs won’t cook your dinner, but a Journal of Preventative Medicine study showed that dog owners were much more likely to meet the recommended 30 minutes a day goal of moderate physical activity. Dogs also help with your mental health. A University of Portsmouth study showed dog owners were less likely to suffer a depressive episode, and that overall, they had a better sense of well-being, social connection, and less loneliness. And dogs’ psychological benefits can extend beyond the home-front. The International Journal of Healthy Workplaces (yes, that is an actual thing) conducted a study on dogs and workplace productivity, finding that workers who could have their canine companions with them at the office had decreased job stress, increased productivity and job satisfaction.

But don’t worry cat people, you guys aren’t totally wrong. Turns out cats have benefits for their owners too. Cat and dog owners both tend to reap the benefits of a statistically significant decrease in the number of times they get sick each year, and many of the psychosocial benefits apply to cat owners as well.

The one place dogs really seem to display a potentially scientifically founded superiority is the arena of asthma and allergy. And I say potential, because there are a lot of conflicting study results out there, some of which cite no change in asthma among kids who had cats or dogs in their house as an infant, but many which do.

For example, the European study which found an increased risk of asthma in children with feline or farm animal exposure early in life vs decrease risk with canine contact. To date there have been a plethora of studies evaluating various aspects of atopy (a genetic tendency to develop heightened immune responses, even allergic diseases, to common allergens – especially to inhaled and food allergens, and animal exposures. The results have been varied.

A large meta-analysis of them, however, reported that among all the animals studied, dogs are the most consistently proven to have positive effect on the immune system. Cats, birds, reptiles, et al, all tended to have neutral or negative effects.

Selfies

Selfies

Dear Dr. K: Among the many challenges and downsides of our smartphones, can you point to any not-so-obvious upsides to these instruments we glue our eyeballs to?

 

As it turns out, today’s craze in smartphone selfies may have some medical value that extends beyond vanity.

To date, three medical conditions have been diagnosable from selfies: pancreatic cancer, skin cancers and oxygen desaturation. It seems other people’s scrutiny of selfies posted on social media can lead to changes being noticed.

In the case of skin cancers on the face, they may be so small or so slow-growing that the individual doesn’t notice the day-to-day change, but others do.  In people with chronic heart or lung conditions a slight change in facial coloration due to reduction in oxygen concentration in the blood may be more readily perceived by others than by ourselves.

Additionally, one of the earliest changes seen in pancreatic cancer can be a very slight scleral jaundice (yellowing of the whites of the eyes). If caught in its early stages, pancreatic cancer has a much better cure rate. Selfies can be very sensitive in catching this early change. So much so that for people with a family history of pancreatic cancer there is a new app – dubbed “Bili Screen” – in which captured pictures can detect slight levels of scleral yellowing (from bilirubin) before this change is even visible to direct observation

Q – Tips: Don’t get burned…

Q – Tips: Don’t get burned…

  • If you are going to get cut or burned, do it during daylight hours. Scientists have discovered a marked circadian (body clock) difference in healing from injuries. Wounds incurred at night take 60% longer to heal than those incurred during daytime hours. There is slower growth of skin cells and collagen when injuries occur at night.
Allergy testing: body’s timing reveals clues

Allergy testing: body’s timing reveals clues

Dear Dr. K: Until my husband recently came to see you I didn’t realize there was any other type of allergy tests than the prick tests I received. Can you explain?

The skin test your husband received was patch-testing to try to ferret the cause of his skin rash. The test is designed to determine if he is sensitive to any contact allergens. The patches are applied and left in place for several days before being read. The test investigates a type of allergy called delayed hypersensitivity (DH).

The tests you received were scratch tests for food and airborne allergies. These assess for a type of allergy called immediate hypersensitivity (IH), which is why the tests are read within minutes of being applied.

These two distinct types of allergies have different physiologic causes. IH is mediated* by an allergic protein called IgE, and accounts for most common allergies such as hay fever, asthma, hives and food allergy. The reactions (and also the tests) are “immediate” because the IgE is a tiny protein distributed throughout the body and bloodstream and can react right away. DH, on the other hand, is mediated* by white blood

cells called lymphocytes that must migrate from the blood stream into the tissue (such as the skin) that is experiencing the allergy. This migration is a bit ponderous, hence, the delayed nature of the allergy (and true results of the test). The tests are read twice: upon removal of the patches and then, 48 hours later.

Familiar examples of this type are rashes from poison ivy or from mango.

 

Allergy Primer

*From the medical dictionary: Mediate: to serve as an intermediary substance.

When you are tested for either type of allergy, what is revealed is that your body has generated these intermediary defenses which help us discern what made you react.

Shingrix now available; better protection from shingles

Shingrix now available; better protection from shingles

Shingrix is the new shingles vaccine which was recently approved by the FDA. It is an improved vaccine for preventing shingles and its complications. Unlike its predecessor vaccine, Zostavax, it requires two doses to be given between two and six months apart.

It is a better vaccine because it uses recombinant technology plus an adjuvant. Recombinant technology means inserting the DNA encoding for the shingles virus into a tissue culture. The culture produces the protein antigens of the virus, but no living virus! These proteins are used to vaccinate.

The adjuvant makes the immune system respond better to the vaccine. This adjuvant (OS-21 Stimulon) is the same one used in the children’s malaria vaccine.

The new vaccine provides much better protection than the original, and is recommended for people 50 and older – regardless of whether they have previously received Zostavax. At this point, cost for both shots is $280. The main side effect is soreness at the vaccine site.

Sensitive – but timely and critical conversation for families to have

Sensitive – but timely and critical conversation for families to have

 Death. Unfortunately, in my line of work, it’s part of my daily life. If you’ve had an appointment with my dad anytime in the past year, you know that I recently shifted gears from an Emergency residency to a Critical Care fellowship. Having spent the last several years in the Emergency Department (ED), I’d forgotten what a different beast death is in the Intensive Care Unit (ICU). In the ED, death is swift, often unexpected and sometimes merciful. ICU deaths however, are frequently prolonged, often excruciatingly so – and in my experience, much more slow, painful experiences for everyone involved.

In the ICU, I often feel like I’m prolonging death and suffering rather than restoring life and vitality. My patients often have more organ systems that have failed than ones still functioning; death is being kept at bay by multiple forms or life support; ventilators, vasopressors, dialysis, ECMO (a form of partial cardiopulmonary bypass), etc. Very rarely is the person who emerges from that cloud of clinical contrivances the same that went into it. More commonly, they are frail shells of their former selves, often without all their faculties, and now condemned to the all-too-common narrative of discharge to rehab facility, where they will continue to linger until they incur one in a long line of complications and end up back in the hospital, often to do the whole thing all over again.

Now, you may say this is a very bleak representative of what the ICU is. Certainly, there are success stories, and not everyone is condemned to this fate. While that is true, those cases are not the impetus behind my writing this column. One of the reasons even frankly futile cases end up languishing on life support for days or months on end is their family’s inability to make complex medical decisions for the patient, which is why Advanced Directives (ADRs) are so important.

While it can be an uncomfortable or awkward discussion for many people to have, it is absolutely imperative that you think about and discuss your goals and wishes before you or your loved one end up in an unfortunate, unforeseen situation. Unless you’ve had a sick family member, or happen to work in health care, you likely have never heard of ADRs. Even those who have may not know everything that can go into them.

And while deciding if you want a breathing tube or CPR are certainly key decisions (described in the “DNR/DNI” portion of an ADR), advanced directives can go way beyond just that. You can make yours as personal and intricate as you want; e.g., blood transfusions, dialysis, feeding methods, surgeries, etc., etc. Or you can stick to the very basic DNR decision. There is a lot to think about and the time to do it is now. Making these choices by no means locks you into anything; you can change, update or rescind any decision at any time.

But where do you even start? Your primary care doctor is a good first stop. He/she likely has a social worker or specialized nurse who can help you through the steps or provide you with worksheets or information pamphlets. Or this person may refer you to a Palliative Care colleague. Family lawyers can be good non-medical resources to assist you through the process as well. Or you can do some research on your own—www.caringinfo.org and theconversationproject.org are both excellent resources.

Q – Tips: Dogs and allergies

Q – Tips: Dogs and allergies

 The University of Chicago just finished a research study showing the benefit of dog ownership in reducing the likelihood of allergies in children born into a pet-owning household. Children born to allergic parents reduced their risk for developing allergies by 33% if born into a household with dogs.