Month: June 2016

“Microbiome” and Allergies

Explained By Allergists McLean VA Patients Trust
There has been an increase in the incidence of allergic diseases over the past 20-30 years and this phenomenon is more pronounced in industrialized countries compared to developing countries.  Many researchers believe that environmental and dietary changes play major roles in the development of allergies.  This is true in areas such as Falls Church, VA, Gainesville, VA, and Tysons Corner, VA as well as the rest of the Washington, DC metro area.

The primary role of our immune system is to defend and protect us from infections caused by germs like viruses, bacteria, and parasites.  Exposure of the immune system to infections with germs in early life stimulates the maturation of the immune system in a normal balanced way.  The absence of this stimulation can trigger the immune system to mistake innocuous substances such as dust mites, molds, pollens, and certain foods as potentially harmful and mount a defensive attack on them causing allergic disease.  This “hygiene hypothesis” aims to explain why more people suffer from allergic disorders in the developed, overly hygienic Western world.  An alternative interpretation of the evidence supporting the hygiene hypothesis forms the basis for the “microflora hypothesis,” which says that rather than specifically limiting infection, even the decreased exposure to microbes changes the colonization of bacteria of the infant gut, which has a negative effect in the development of the normal immune system which ultimately leads to allergic disease.

An adult human harbors about 100 billion bacteria in the intestines alone.  These gut bacteria account for 90% of the cells in the human body!  Human cells contain about 21,000 different genes, but the microbes living in the human comprise about 3 million genes.  The composition and function of the bacteria in the gut varies from person to person (i.e., biodiversity) and evolve during the first years of life and stabilize within the first 3 years of life.

The development of the gut microbiome (i.e., all the microorganisms that live in the gut) is influenced by interactions between diet, environment, and host-associated factors.  There is increasing evidence that these bacteria play many helpful roles in the modulation of our immune responses, especially in maintaining a balance between 2 different types of white blood cells called Th1 lymphocytes and Th2 lymphocytes.  The Th1 lymphocytes help protect us from infections, whereas the Th2 lymphocytes help mediate allergic disease.

The emerging hypothesis infers that environment or lifestyle-driven aberrancies in the early-life gut microbial composition and function represent a key mediator of childhood allergies and asthma.  Significant perturbations in the gut bacterial composition, especially reduced diversity, in the Western societies due to frequent antibiotic usage, environmental and lifestyle changes, etc. have disrupted the mechanisms of mucosal tolerance leading to more allergic disease.

Epidemiologic and clinical data supporting this interpretation include:

  1. A positive correlation between increasing risk for asthma and allergies and increasing use of antibiotics in industrialized countries.
  2. Correlations between altered fecal microbial flora and atopic disease
  3. Successful prevention and/or reduction of allergies in some individuals by the use of oral probiotics (live commensal bacteria) and dietary changes.

A recent meta-analysis of 25 studies revealed that the administration of probiotics reduces allergy-causing IgE antibody levels and the risk of atopic sensitization.  An example of dietary factors influencing allergies is the landmark LEAP study which demonstrated that early introduction of peanut products to high risk infants significantly decreased the subsequent development of peanut allergy.

There are a number of ongoing studies which will improve our understanding of the mechanisms underlying allergic disorders and hopefully offer new and exciting options in the management of these conditions in near future.

The board certified allergists of Black & Kletz Allergy always strive to keep abreast of new developments in the field of Allergy, Asthma, and Immunology in order to offer new and emerging diagnostic and therapeutic modalities, as soon as they are available.  Black & Kletz Allergy has 3 offices in the Washington, DC, Northern Virginia, and Maryland metropolitan area.  We have offices in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA and offer on-site parking at each location.  In addition, the Washington, DC and McLean offices are Metro accessible.  There is a free shuttle that runs between the McLean office and the Spring Hill metro station on the silver line.  The allergy specialists of Black & Kletz Allergy see both adults and children in the Tysons Corner, VA, Falls Church, VA, and Gainesville, VA areas and we have been serving the greater Washington metro area for over 50 years.  Please call one of our convenient offices to make an appointment or alternatively, you can click Request an Appointment and we will reply within 24 hours by the next business day.

Air Quality and Its Effects on Allergic Individuals

The Washington, DC, Northern, Virginia, and Maryland metropolitan area has its share of pollutants in its air as well as the many allergens that are known to be prevalent. The allergens that are common in the DC metro area include tree and grass pollens in the Spring, ragweed pollen in the Fall, and mold spores which are perennial in nature. The molds are year-round due to the history of Washington, DC being a swamp many years ago. The humidity also tends to be high in the area, which favors the growth of molds. Regarding pollutants, there are many different types of pollutants in the Washington, DC metropolitan area including such cities as Gainesville, VA, Falls Church, VA, and Tysons Corner, VA.. Some of these pollutants include carbon monoxide, ozone, organic dusts and other fine particulate matter, nitrogen dioxide, sulfur dioxide, and lead emissions.

It is not news to anyone that the traffic in the Washington, DC metro area is sometimes horrific. Not only does it play havoc with people’s temperament, but so many motor vehicles produce emissions which contribute greatly to the air pollution and thus the air quality of the area. In the summers, this pollution tends to be worse. The sunny days will produce increased levels of ozone which has been determined to be hazardous to one’s health, particularly people with lung disease such as people with asthma and chronic obstructive pulmonary disease (COPD). Chronic bronchitis and emphysema are the two most common conditions that contribute to COPD.

Almost all patients with allergic rhinitis (i.e., hay fever) and/or asthma know a lot about the pollen count and what it means. The pollen count is the number of pollen grains in one cubic meter of air. For example, if the pollen count for tree pollen is 250, it means that there are 250 grains of tree pollen in a sample of air that is 1 meter X 1 meter X 1 meter. Keep in mind that 1 meter is 39.37 inches. Different locations throughout the U.S. have different guidelines depending on the types of pollens they have and the quantity of the pollen released into the air. As a general rule, the pollen count levels can be interpreted by the following values: Trees – 1-14 is Low; 15-89 is Moderate; 90-1,499 is High; 1,500 and above is Very High. Grasses – 1-4 is Low; 5-19 is Moderate; 20-199 is High; 200 and above is Very High. Weeds – 1-9 is Low; 10-49 is Moderate; 50-499 is High; 500 and above is Very High. Molds – 1-6,499 is Low; 6,500-12,999 is Moderate; 13,000-49,999 is High; 50,000 and above is Very High. In fact, you can always click Today’s Pollen Count at the top of our website to see the latest pollen count for the Washington, DC, Northern Virginia, and Maryland metropolitan area. Many individuals use this knowledge to help them guide when they should avoid certain outdoor activities. Generally, the pollen counts are the highest in the mornings through midday. Planning to do outdoor activities, such as exercising or doing yard work, in the evening is usually recommended to minimize pollen exposure.

In addition to being aware of the pollen count, it is also important to be aware of the Air Quality Index (AQI). The AQI indicates how polluted the air is in your area. The AQI is calculated based on 5 major pollutants which include carbon monoxide, nitrogen dioxide, sulfur dioxide, fine particulate matter, and ground-level ozone. The last two pollutants (fine particulate matter and ground-level ozone) pose the greatest threat to an individual’s health. The AQI is divided into 6 different zones of increasing amounts of pollution and thus health risk. The zones are color-coded and in order from less pollution to more pollution are as follows: Green, Yellow, Orange, Red, Purple, and Maroon. In the Washington, DC area, it is not uncommon to have a few “Code Red” days during the summer, particularly when it is hot, humid, and sunny. “Code Green” is the best air quality and poses little or no risk of any health concern. “Code Yellow” signifies acceptable air quality and may pose a moderate health concern for a very small number of people who are very sensitive to air pollution. “Code Orange” indicates an unhealthy quality of air for some sensitive groups of people. “Code Red” means that the air quality is generally unhealthy for the general public, although usually only sensitive groups will experience more serious health effects. “Code Purple” notifies the general public that the air is very unhealthy and tends to occur in emergency conditions, such as when there is a chemical spill. “Code Maroon” indicates hazardous conditions where everyone will most likely experience untoward health issues. Generally, it is recommended to stay indoors when the level is “Code Red” and above.

The board certified allergists of Black & Kletz Allergy treat patients of all ages including children and the elderly in the Falls Church, VA, Tysons Corner, VA, and Gainesville, VA areas. Children and elderly persons tend to be more sensitive to poor air quality, as well as individuals with lung conditions such as asthma and COPD. Black & Kletz Allergy has 3 office locations in the Washington, DC, Northern Virginia, and Maryland metropolitan area with offices in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA. The Washington, DC and McLean offices are Metro accessible and there is a free shuttle that runs between our McLean office and the Spring Hill metro station on the silver line. If you would like to make an appointment, please call us or you can click Request an Appointment and we will respond within 24 hours by the next business day. The allergy doctors of Black & Kletz Allergy have been serving the greater Washington, DC metro area for more than 50 years and we pride ourselves in excellent quality allergy, asthma, and immunology care in a friendly, caring, and professional environment.