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Month: December 2016

Alas, what we have wrought

Alas, what we have wrought

Allergic diseases arise in response to normally innocuous environmental agents, including airborne allergens and the foods we eat.

Why does the immune system cause this mischief and why is it becoming so prevalent?

The answer to both these questions is T-regs.

T-regs, better known as T-regulatory lymphocytes, were first discovered about 20 years ago. However, over the past 10 years scientists have learned the vital role they play in causing allergy. As their name implies, these cells regulate the immune system. When they function normally they regulate the immune system to be tolerant to airborne allergens and foods (that is, to be non-allergic).

As it turns out, it seems to be the proinflammatory environment created since the industrial revolution that has caused the T-regs to go awry. The main environmental factors are modern chemicals, petroleum exhausts, plus our water and food supply that contains chemicals and antibiotics.

One of the biggest arenas in immunologic research is to find a way to get the T-regs back into a friendly mode, despite the pro-inflammatory environment we have created for ourselves.

 

Dear Doc: So carbon monoxide not always harmful?

Dear Doc: So carbon monoxide not always harmful?

Dear Dr. K: I’ve always heard that carbon monoxide is deadly, but then I read it’s being researched as a transplant medicine. What gives?

What gives is the dynamic of toxic levels versus helpful levels. There are many examples of this in the history of medicine. For example, in the pre-antibiotic era, heavy metals such as gold, silver and arsenic were used to treat infections, in very controlled doses.

Even oxygen, which we breathe every day, and can be supplemented for hospitalized patients can be toxic if given at too high a dose.

The same turns out to be true with carbon monoxide (CO). It wasn’t until fairly recently that scientists discovered humans actually produce CO, and that it plays a vital role in many bodily processes.

In the brain, it is a neuro-transmitter, important in learning and memory. In the heart, it keeps blood vessels wide open. In the liver, intestines, kidneys, lungs and reproductive organs it improves natural functions. And in the immune system it improves host resistance and lessens undesirable inflammation.

It is this last property that has led to the research you are alluding to in organ transplant rejection. Carbon monoxide has been shown to prevent transplant rejection in several animal models; it hasn’t been studied yet in humans.

Because CO reduces inflammation it also is being studied in traumatic brain injuries, multiple sclerosis, pulmonary fibrosis and atherosclerosis – all of which have unwanted inflammation as a common denominator.

Three methods of delivering CO as a treatment are being studied: breathing in small amounts, using CO-releasing compounds and using pro drugs to generate extra CO.

Perhaps being stuck in traffic has an upside.

DRESS: Short name for scary new allergic reaction

DRESS: Short name for scary new allergic reaction

DRESS, a helpful acronym for Drug Reaction with Eosinophilia and Systemic Symptoms, is a newly recognized form of allergic reaction. Potentially quite severe, it is important to recognize and stop the offending medication and start proper treatment. The exact pathogenesis is still not fully understood, but it seems to occur because of immune response and reactivation of a latent herpes virus.

A form of rash with facial redness and swelling is common, but a measles-type rash also can occur. Other common symptoms include fever, achiness and lymph node swelling. The most frequently affected internal organs are the liver and kidneys. Blood work can show elevated liver enzymes and kidney factors, and reveal an elevation in a specific white blood cell called the eosinophil.

The drugs most often found to cause DRESS are anticonvulsants and sulfur drugs. Others that have been implicated are Gleevec (an anti-cancer drug), various antibiotics, Amlodipine (a blood pressure medicine), and NSAIDS (non-steroidal anti-inflammatories).

As mentioned above, recognizing DRESS as soon as possible is important so the offending drug can be discontinued. The most effective therapy is the use of steroids. In life-threatening cases, intravenous immunoglobulin has been used.

So far, despite the interplay of viral interaction in causing the condition, no studies have been done on the use of antiviral therapy.

One less parental worry

One less parental worry

Harvard researchers at Boston Children’s Hospital recently finished a detailed study of the use of acetaminophen in asthmatic children. The outcome allows for a sigh of relief.

In 2000 British researchers questioned whether acetaminophen use led to exacerbation of wheezing in children. The concern arose because when children are sick with respiratory infections, this common, over -the-counter drug is frequently used to treat fever. So, the question arose: was it the illness itself or, perhaps, the acetaminophen that caused worsening of asthma?

One reason acetaminophen was a suspect is because it is known to temporarily reduce glutathione in the lungs – a natural compound that has anti-oxidant properties. Because of these concerns, many pediatricians in the U.S. and the U.K. were shying away from the use of acetaminophen in asthmatics. It was for this reason that Harvard undertook a randomized prospective study.

Their results were very reassuring. They found no increased risk of worsening asthma in the acetaminophen group versus the “control group.” Thus, they concluded it is safe to use, and that it’s the infection that worsens the asthma, not the popular drug.

Q – Tips: Food and migraines

Q – Tips: Food and migraines

Foods known to induce migraine headaches include cheeses (especially aged cheeses), chocolate, chicken liver, beer, wine, nuts, mushrooms, smoked/pickled meat and fish, bouillon cubes, yoghurt, eggs, soy sauce, MSG and foods with nitrites (hot dogs, bacon, deli-meats).