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Month: February 2011

Quick Tips – Natural killer cells

Quick Tips – Natural killer cells

Recent research on natural killer cells (NK cells) has discovered that these provide not only innate immunity, but also adaptive immunity. Innate immunity is a primitive, non-discriminatory resistance against all foreign invaders. Adaptive immunity is a learned behavior requiring inter-cellular communication.

Quick Tips – Second-hand smoke

Quick Tips – Second-hand smoke

Scientists in Sweden who did a study on second-hand smoke exposure worldwide found that 40 percent of children, 33 percent of non-smoking males and 35 percent of non-smoking females got second-hand smoke exposure to a degree that it shortens life spans, and adversely affects their health.

Phototherapy vs. nasal allergy

Phototherapy vs. nasal allergy

Dear Dr. K: I read a report that said sunlight can help nasal allergies. Is that true?

Yes, it is true. It has been known for years that sunlight can exert beneficial immune effects.

The report you read was probably one about recent research using intra-nasal phototherapy. The most recently published article in this regard is from the journal, “Therapeutic Advances in Respiratory Diseases,” and was a well-done, placebo-controlled, randomized study.

Before discussing that research, let’s look at phototherapy in general. This modality has been used for years in treating a variety of inflammatory skin conditions. (Keep in mind that nasal allergy is also an inflammatory condition.) The most common skin conditions that respond to phototherapy (UV-A and UV-B) are acne, eczema and psoriasis. Phototherapy exerts a number of immune modulating effects, the primary one being to reduce molecules of inflammation such as prostaglandins.

The study done on nasal allergy used a phototherapy that consisted of 25 percent UV-A, 5 percent UV-B and 70 percent visible light. The treatment time gradually increased from two minutes to three minutes.

Compared to the placebo group there was marked improvement in nasal obstruction, itching, mucous production and sneezing. The only side effect of the treatment was nasal dryness in a few patients.

If these findings hold up to further clinical trials, phototherapy might become a viable option for some allergic patients such as those intolerant of medicines or those unable to take allergy shots.

New guidelines can help diagnose food allergies

New guidelines can help diagnose food allergies

The American Academy of Allergy, Asthma and Immunology (AAAAI) has just released guidelines for diagnosing and managing food allergies. These guidelines were conceived because of a lack of uniformity among physicians in testing and treating food allergy.

Frequently, pediatricians, family physicians and internists will order tests for food allergy. It is especially important that non-allergist physicians – as well as allergists – have a standard guideline for handling food allergy issues.

The AAAAI starts by pointing out that food allergy is common, but that many persons also have adverse reactions to foods that are non-allergic in origin. Proper testing/evaluation can separate these disparate conditions.

The AAAAI notes that the most common food allergens are milk, eggs, peanuts, tree nuts, shellfish, wheat and soy. The natural tendency is for an individual to outgrow the allergy. This is true for most foods, and studies have found that 80 percent of children outgrow their food allergies. This, however, is not true for peanut, tree nut and shellfish, where statistics show that only 20 percent of children outgrow these allergies.

The AAAAI makes a strong point that a positive test does not necessarily mean the patient has a true allergy to the food. What is also needed is a relevant history of prior reaction to the tested food or a confirmation of the test by an oral challenge. Oral challenges can be done at home following an elimination period. In cases of severe anaphylactic food allergies, food challenges may be done in an allergist’s office or in a hospital.

The most sensitive mechanism for testing is skin testing which measures IgE levels to the food. The RAST test, ELISA or Immunocap are blood tests for IgE.

Some labs offer a non-standard IgG food test which has no relevant value in diagnosing food allergy.

Stinging Insect Pain Index – This hurts to read!

Stinging Insect Pain Index – This hurts to read!

Not infrequently, allergists are faced with a patient who has had an allergic reaction to an insect but has not been able to identify the culprit. Allergy testing can help identify the cause of the allergy. In cases where the allergy was mild and testing was therefore not warranted, another way to identify the elusive critter is the Schmidt Sting Pain Index. Justin O. Schmidt subjected himself to the stings of 78 species and 41 genera of hymenoptera. He developed a pain scale from 0 to 4. He also added personalized distinctions between the insect stings.

Some cogent examples from the pain index:

 1.0 Sweat bee: light, ephemeral, almost fruity. A tiny spark has singed a single hair on your arm.

 1.2 Fire ant: Sharp, sudden, mildly alarming. Like walking across a shag carpet and reaching for the light switch.

 1.8 Bullhorn ant: A rare, piercing, elevated sort of pain. Someone has fired a staple into your cheek.

 2.0 Hornet: Rich, hearty, slightly crunchy. Similar to getting your hand mashed in a revolving door.

 2.0 Yellow jacket: Hot and smoky, almost irreverent. Imagine W.C. Fields extinguishing a cigar on your tongue.

 2.0 Honeybee: Like a match head that flips off and burns your skin.

 3.0 Harvester ant: Bold and unrelenting, someone is using a drill to excavate your in-grown toenail.

 3.0 Paper wasp: Caustic and burning with a distinct bitter aftertaste; like spilling hydrochloric acid on a paper cut.

 4.0 Pepsis wasp: Blinding, fierce, shockingly electric — a non-fatal version of a running hair drier being dropped into your bubble bath.

 4.0+ Bullet ant: Pure, intense, brilliant pain; like fire-walking over flaming charcoal with a 3-inch rusty nail in your heel.