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Author: Stephen J. Klemawesch, MD

My aging immune system…and flu shots

My aging immune system…and flu shots

 Dear Dr. K: I read that since I’m 68 years old I won’t get as good immunity from the flu shot as a 30-year-old. Am I wasting time by getting vaccinated?

The complete and total answer to your question is “No.” However, let me elaborate.

The issue at hand is immunosenescence, or aging of the immune system. Just like other parts of our body, our immune systems age. It is for that reason that persons over age 50 are more likely to get shingles and to die from influenza. We (I can say that since I’m over 50) also are more likely to get bacterial pneumonia, urinary tract infections, meningitis, gastroenteritis and tuberculosis.

Because of these risks, it makes it all the more important to take preventive steps to bolster our immunity.

People over 65 get only 56 percent of the protective effect of flu vaccine and only 65 percent of the protective effect of the pneumonia vaccine, as compared to young people. Still, that 56 and 65 percent improvement is better than 0 percent.

There has been intense research on the aging immune system, especially with the wave of baby boomers enlarging the elderly population. One unexpected finding was that in addition to increased risk of infection in people over 50, there is a specific infection that by itself can actually speed the senescence of the immune system. The culprit is a virus called CMV – Cytomegalovirus.

As it turns out, this dastardly virus reduces the helper T-cell lymphocytes which are so important in building good immune function. CMV is in the family of herpes viruses and once you’re infected, it stays with you life long.

Since CMV is fairly common, there is intense research into finding a way to prevent its immunologic mischief.

Big word, important concept – Dermatographism

Big word, important concept – Dermatographism

Dermatographism is a term that comes from Greek and Latin words dermos (skin) and graphia (to write). It literally means to write in the skin and thus, describes an exaggerated cutaneous response to physical stimuli in the form of hives.

The physiologic mechanism is histamine degranula-tion from mast cells in the skin by mechano-immuno-logic triggers. Thus, systems of burning, itching, redness and welting occur from pressure such as tight clothing, belts and bra straps.

Stroking the skin or scratching can also lead to symptoms, as can continuous pressure such as sitting (on your buttocks) or standing (on your feet).

There are some subtypes of dermatographism such as the cholinergic form. This form is worse when the body is heated as from exercise, a hot shower or a fever. Follicular dermatographism tends to center around hair follicles and manifests as several papules rather than larger welts.

White dermatographism is, as the name implies, blanching of the itchy skin rather than redness, and is due to vasoconstriction (blood vessel narrowing). Cold-dependent dermatographism requires cold exposure.

Dermatographism can be primary (inherited) or secondary. Secondary can be systemic disease-induced such as hyperthyroidism, diabetes and mastocytosis; drug-induced as in allergic reactions (especially to amoxicillin, cephalosporins, atorvastatin and famotidine); from infectious triggers (this is especially common in children with strep infections and viruses), and from psychological factors such as stress and anxiety.

The mainstay of treatment is antihistamine drugs. Usually a combination of a histamine one (H1) receptor blocker and a histamine 2 (H2) receptor blocker is required. A combo that often works well is Zyrtec (H1) and Zantac (H2).

In more severe cases a third drug can be added – a leukotriene modifier (Singulair or Accolate). Also, phototherapy using narrow-band UVB has been shown to be helpful.

Quick Tips – fire ants

Quick Tips – fire ants

Fire ants are wingless bees and they sting with an abdominal stinger while holding on with their jaws. (Eeeww! and Ouch!)  The allergic reaction is to the sting, not the bite. When gardening or picnicking, be sure to wear shoes and socks to make fire ant contact less likely.

Quick Tips – barbecuing

Quick Tips – barbecuing

When barbecuing, keep in mind the issue of second-hand smoke. Be sure to position the grill in such a way that the smoke blows away from adults and children. Some people with oak or hickory allergy are more sensitive to these flavoring wood chips.

Quick Tips – insect bites

Quick Tips – insect bites

Insect bites and stings can hamper an active outdoor lifestyle. For people sensitive to bug repellants there is a new line of clothing, hats and scarves that are impregnated with a safe, effective repellant.  This clothing is widely marketed in catalogs and on websites.

More lung injury from smoking

More lung injury from smoking

Researchers at the University of Alabama Medical Center have discovered a new reason cigarette smoke causes lung damage.

They found that smoke inhibits leukotriene A4 hydrolase (LTA4A). This molecule is important in shutting down white blood cells following a successful response to inflammation. By not shutting down white blood cells, smokers experience ongoing inflammatory damage to the lung and airways; this leads to COPD and emphysema.

The same researchers also discovered previously unknown substrata of LTA4H called proline-glycine-proline (PGP), which actively recruits white blood cells into lunch tissues.

Discovering these two molecules naturally helps understand how smoking injures lungs, but may also lead to research that allows manipulating these molecules to reduce lung injury.

This could be of benefit not only for smoke-related lung disease, but also for other inflammation problems such as asthma and cystic fibrosis.

LTRA’s

LTRA’s

 

The lead article in a recent issue of the New England Journal of Medicine was on leukotriene antagonists in treating asthma. The lead-article status reflects the importance of this research.

As reported, scientists at the University of Aberdeen, U.K., evaluated leukotriene antagonists in two ways.

The first part of the study compared the adding of inhaled steroids to the adding of leukotriene antagonists as add-on therapy for control of asthma. In the hundreds of patients they studied, the researchers found the two therapies to be equally effective. Both restored asthma control so that symptoms improved and the need for rescue medication was reduced.

The second prong of the study looked at patients who were already on an inhaled steroid but still needed more controller help. Again the patients had additional therapy either in the form of a leukotriene antagonist or a long-acting bronchodilator (Salmeterol).

Both groups improved with the add-on medication, and the improvement was similar in both groups.

The leukotriene antagonist used in this study was montelukast (Singulair), but there are two other drugs in this family – Accolate and Xyflo. They work by reducing the inflammation that causes asthma. This is also how steroids work.

Hum Away Your Sinutitis

Hum Away Your Sinutitis

Simple viruses or colds can often lead to sinusitis because the cold causes the sinus cavity to obstruct, thus trapping bacteria in a closed space. Once in this closed space, bacteria multiply and lead to the pain and pus of sinusitis.

Keeping the sinuses healthy and bacteria overgrowth-free requires good ventilation of the sinuses.

A recent article in the American Journal of Respiratory and Critical Care Medicine cited a research project on humming. The scientists conducting this study found that humming leads to higher levels of exhaled nitric oxide, a gas produced in the sinuses.

It seems that humming exerts a positive pressure into the sinuses in a fluttering way that promotes their unblocking.

Another research group also studied humming and sinusitis and published their data in the European Respiratory Journal.

Both groups found that repeated humming sessions during days when people had colds markedly reduced the incidence of sinusitis.