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Month: December 2017

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.