Another recent study from that publication found that people with the chronic allergic “triad” of rhinitis, asthma and eczema have a much greater risk of developing Sjogren’s Syndrome (an auto-immune condition causing dry eyes and mouth) than the general population.
Twenty percent of children with milk allergy will also be allergic to beef, according to Allergy and Asthma Proceedings.
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.
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.
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.
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
• Harvard researchers have confirmed that Vitamin D supplements in pregnant women significantly reduce the chance for their children of developing asthma. It seems that this benefit is conferred primarily in the first trimester of pregnancy.
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 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.