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Month: August 2021

Common Variable Immunodeficiency

Our immune system defends us against microorganisms that cause infections. It also protects us from certain cancers. Thus when the immune system functions sub-optimally, we are more susceptible to infections and cancers.

Common variable immunodeficiency (CVID) is one of the most common conditions where the immune system is deficient or less functional.


It is thought that genetic defects are most likely the underlying cause for this condition, although specific gene defects were identified in only 10% of the cases. Common variable immunodeficiency is known to occur more commonly in certain families which also suggests a genetic cause.
Males and females are equally affected in CVID. Common variable immunodeficiency occurs in approximately 1 out of every 25,000 individuals. Even though the condition is present from early childhood, it is most commonly diagnosed in the second or third decades of life.


The most common presentation of CVID involves recurrent infections involving various organ systems. The infections are typically as specified below:

  • Upper respiratory and/or sinus infections
  • Ear and/or throat infections
  • Bronchitis and/or pneumonia
  • Gastrointestinal infections
  • Neurological infections
  • Fatigue, joint pains (i.e., arthralgias), and/or muscle pains (i.e., myalgias)

The infections can vary in severity from mild to severe. Many patients require emergency room visits and/or hospitalizations for the management of severe infections.

Physical examination sometimes reveals enlarged lymph nodes and rarely skin rashes.


The diagnosis of common variable immunodeficiency is initially suspected on the basis of a history of recurrent infections for a number of years, often with unusual or rare organisms.

Confirmation of the diagnosis is completed by blood tests which reveal lower numbers of lymphocytes and antibodies (i.e., proteins that fight infections) compared to normal reference levels. Measuring antibody levels before and after vaccinations is also helpful in testing the ability of the immune system to manufacture specific antibodies. It should be noted that CVID patients cannot respond to immunizations adequately and thus do not mount a good immune response to vaccinations.


  • Antibiotic treatment for infections: Patients need prolonged courses of antibiotics in order to adequately treat severe bacterial infections.
  • Prophylactic antibiotics: Patients require prophylactic antibiotics in order to prevent infections prior to surgical and/or dental procedures.
  • Antibody supplementation: Most patients need regular infusions of antibodies, which are pooled from donors, either through a vein (i.e., intravenous) or under the skin (i.e., subcutaneous) on a regular basis. This treatment maintains the integrity of the immune system and helps prevent frequent and repeated infections. This treatment, known as gamma globulin therapy (i.e., immunoglobulin therapy, antibody replacement therapy), needs to be continued lifelong, as there is no cure for common variable immunodeficiency.


Patients with CVID are more likely to develop autoimmune disorders affecting the thyroid gland, liver, and connective tissues. Autoimmune conditions may also attack blood cells resulting in anemia and/or low platelet counts. Low platelet counts usually manifests itself as easy bruisability and/or increased bleeding.

Individuals with common variable immunodeficiency are also more susceptible for certain types of cancers and granulomas (i.e., inflammatory swellings) in the skin, lymph nodes, stomach, and/or liver. For this reason, patients need regular monitoring, surveillance, and screening for these type of cancers. It is recommended that all individuals with this disorder follow up with their primary care physician on a routine basis in order to be diligent in this regard.


With regular antibody replacement therapy, prophylactic and curative antibiotic regimens, and close monitoring for complications, most individuals with CVID can lead long and fulfilling lives.

The board certified allergy doctors at Black & Kletz Allergy have 3 convenient office locations in the Washington, DC, Northern Virginia, and Maryland metropolitan area and are very experienced in the diagnosis and treatment of immunodeficiency disorders such as common variable immunodeficiency. Black & Kletz Allergy treat both adults and children and have offices in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA. We offer on-site parking at each location and the Washington, DC and McLean, VA offices are Metro accessible. There is a free shuttle that runs between the McLean, VA office and the Spring Hill metro station on the silver line. Please call our office to make an appointment or alternatively, you can click Request an Appointment and we will respond within 24 hours by the next business day. The allergy specialists at Black & Kletz Allergy have been serving the Washington, DC metropolitan area for more than 5 decades. We pride ourselves in providing excellent immunological care as well as exceptional allergy and asthma care in a professional and friendly setting.

Reactions to Food Additives

The food we consume everyday contains many natural and artificial additives. Most of these additives to food are chemicals and biological substances. In most of the cases, they are usually either preservatives or coloring substances.

Though additives have been used for hundreds of years, there has been an increase in the number and variety of substances added to food in the past few decades. The Food and Drug Administration (FDA) lists more than 4,000 different additives on their Food Additive and Color Additive lists.

Some of us can be “intolerant” to food additives, however, food additives may cause both immediate (i.e., symptoms beginning within a few minutes of eating food) and/or delayed (i.e., symptoms beginning several hours after eating food) hypersensitivity reactions. Immediate reactions are mediated by an antibody called IgE and delayed reactions are usually caused by T-lymphocytes (i.e., T-cells). The exact mechanism of reactivity however, may be unknown in a number of reactions caused by the additives.

Two common additives found in food in the U.S. that need special mention include sulfites and food dyes.


Sulfites are one of the most commonly used preservatives for foods. They reduce spoilage and prevent fruit and vegetable browning. They also have some beneficial anti-oxidant properties. Sulfites are present in dried fruits in high quantities. They are also usually added to baked goods, shrimp, and condiments. Sulfites are also present in several varieties of wines and beers.

There are many case reports of sulfites causing hives (i.e., urticaria), angioedema (i.e., soft tissue swellings), and flare-ups of asthma. The FDA now requires that most preservatives, including sulfites, be cleared mentioned in the food labels. Sulfites can appear as alternate verbiage on product labels and can be written as potassium bisulfite, potassium metabisulfite, sodium bisulfite, sodium metabisulfite, or sodium sulfite.

Sulfite, sulfa, sulfate, and sulfur are 4 terms that sound very similar but are very different when it comes down to their allergy profile. Sulfa drugs contain the sulfonamide molecule and are typically broken down to sulfonamide antimicrobials (i.e., antibiotics) and sulfonamide non-microbials. The chemical structures are different between the sulfonamide antimicrobials and the sulfonamide non-microbials and thus individuals who have allergic reactions to one group should not have allergic reactions to the other group of sulfonamides. It should be noted that approximately 3% of individuals are allergic or have adverse effects from sulfonamide antimicrobials. The sulfonamide antibiotics may include sulfamethoxazole (i.e., Bactrim, Septra), sulfafurazole, sulfisoxazole (i.e., Pediazole), and sulfadiazine. The non-microbial sulfonamides may include Celebrex (i.e., celecoxib), Lasix (i.e., furosemide), Microzide (i.e., hydrochlorothiazide), Imitrex (i.e., sumatriptan), Amaryl (i.e., glimepiride), and Diabeta (i.e., Glyburide).

Sulfates are present in many medications (i.e., magnesium sulfate, ferrous sulfate), supplements (i.e., glucosamine sulfate), and personal care products (toothpaste, shaving foam, shampoo). Sulfates are different chemically from sulfites and sulfa drugs and are unlikely to cause allergic reactions.

Sulfur is a chemical element and omnipresent. It is thus practically impossible to have an allergy to sulfur.

Food Dyes:

Carmine is a coloring agent present in red-colored foods. It is extracted from the insect known as the cochineal. It is known as “cochineal extract” or “natural red 4.” It has been shown to cause facial swelling, rashes, wheezing, and/or anaphylaxis.

Saffron, annatto, and yellow dye # 5 are added to foods to color them yellow. Saffron is a spice that has been around for thousands of years. It can be toxic in larger quantities. An allergy to saffron is known to cause itching, skin irritation, rashes, redness of the skin, and hives. Annato comes from the seeds of the achiote tree and can be found in some cereals, drinks, cheeses, and snack foods. It has been shown to cause rashes and anaphylaxis is some individuals. Yellow dye # 5 (i.e., tartrazine) is known to cause hives and angioedema is selected individuals. It is also known to trigger asthma in some individuals.

It is important to note that any food dye may cause allergic reactions in susceptible individuals. Although food dye allergies are not too common, it is important to be aware that reactions such as itchy skin, redness of the skin, hives, angioedema, and anaphylaxis may occur.


If one experiences untoward reactions to many different unrelated foods or if reactions occur only after eating commercially packaged foods, sensitivity to the additives should be suspected. Maintaining a food and symptom diary can be helpful in narrowing down the additive in question by establishing a temporal relationship between exposure and the onset of adverse effects.

Skin prick testing or blood testing are not useful in the diagnosis of food additive sensitivity; however, they may be useful in ruling out specific foods. Oral food challenges are usually helpful in the diagnosis. In this procedure, foods are eaten in small increments at regular intervals, beginning with a tiny quantity, while closely monitoring for adverse reactions under controlled circumstances with standardized protocols to treat an allergic reaction.


Avoidance of the foods containing the suspected or confirmed sensitizing additive is essential in order to prevent untoward reactions. Careful reading of labels before eating is essential in reducing the likelihood of reactions. Enquiring about the specific ingredients of a dish in restaurants will go a long way in preventing untoward symptoms.

Patients with a history of anaphylaxis triggered by either known or unknown substances should always carry a self-injectable epinephrine device (e.g., EpiPen, Auvi-Q, Adrenaclick) at all times. If the device is used, the patient must go immediately to the closest emergency room.

More and more natural and artificial chemicals are being added to our food as preservatives, flavor enhancers, and coloring agents.  The U.S. Food and Drug Administration (FDA) lists close to 4,000 substances as food additives.

Despite widespread use of these chemicals in food, adverse reactions are fortunately uncommon.  Most cases are described in the literature as single case reports or reports of a small cluster of patients.


Sulfites:  These chemicals in the gaseous form can cause lung irritation and may trigger asthma in sensitive asthmatics.  They are commonly found in liquid form in processed cold drinks and fruit juice concentrates in order to extend their shelf lives.  Sulfites are also added to most wines and sprayed onto cut foods in order to keep them fresh and prevent discoloration or browning. They are used to preserve smoked and processed meats, dried fruit (e.g., apricots), and salads.  In its solid form, sulfites can cause hives when ingested.

Benzoic acid (i.e., benzoate) and Parabens:  Benzoates and parabens have antibacterial and anti-fungal properties in order to help with the prevention of food spoilage.  These agents are added to pharmaceutical and food products such as drinks (e.g., sugar-free cola). They occur naturally in prunes, cinnamon, tea, and berries.  These substances may cause urticaria (i.e., hives), asthma and angioedema (i.e., swelling) in sensitive individuals.

Antioxidants:  Synthetic phenolic antioxidants [e.g., BHA (butylated hydroxyanisole) and BHT (butylated hydroxytoluene)] are typically added to processed foods such as dry cereals and potato flakes in order to prevent the fats and oils in these foods from turning rancid when exposed to air.  Unfortunately these antioxidants may trigger asthma, rhinitis, and urticarial in some sensitive individuals.

Flavor Enhancers:

Aspartame (e.g., NutraSweet, Equal), a low-calorie sweetener, can occasionally trigger itchy hives and swelling of the body.  It is also important to note that individuals with genetic condition phenylketonuria should avoid aspartame. Aspartame breaks down into an essential amino acid called phenyalanine which is toxic to individuals with phenylketonuria since these patients are unable to metabolize phenyalanine.


Azo dyes [e.g., tartrazine (i.e., yellow dye #5)] and Non-azo dyes (e.g., erythrocine) can trigger hives, asthma, and generalized allergic reactions.

Nitrates and Nitrites give meat a pink color to look more attractive.  These food colorings are typically found in bacon, salami, and frankfurters.

Monosodium Glutamate (MSG) may trigger the “Chinese Restaurant Syndrome” which causes individuals to experience headaches as well as burning and/or tightening of the chest, neck, and face.  MSG may be found in soups, pot noodles, and instant drinks, among other foods.

Naturally Occurring Substances:

Vasoactive amines: Natural histamine, serotonin, and tyramine occur in some ripe cheeses, fish, cured sausage, red wine, chocolate, and pickled vegetables and may induce cramping, flushing, headache, and palpitations in a dose-related manner.  Of note, there is a condition known as “scombroid poisoning” which occurs in individuals who eat spoiled fish. In this condition, there are abnormally high quantities of histamine in the fish due to improper storage or processing.  The typical fish affected may include tuna, mackerel, herring, sardine, anchovy, marlin, and bluefish. The symptoms may include flushing, headache, generalized itching, blurred vision, abdominal cramps, and/or diarrhea. Scombroid poisoning is often wrongly diagnosed as a fish allergy since similar symptoms may be associated with a true fish allergy.  One key factor to look for is to see if other individuals eating the same piece of fish exhibited symptoms. If so, it is more likely to be scombroid poisoning due to eating spoiled fish as opposed to a fish allergy.

Caffeine found in foods, medication, tea, coffee, and carbonated beverages induces dose-dependent agitation, palpitations, nausea, and/or tremors.

Salicylates (i.e., aspirin-like naturally occurring chemicals) may induce urticaria, asthma, and/or nasal polyp growth.  They are found in curry powder, paprika, oranges, apricots, ginger, honey, berries, fruit skins, tea, and almonds.  Salicylate sensitive individuals also tend to have adverse reactions to benzoates and tartrazine.


The precise mechanism how food additives cause reactions is not well understood in many instances.  The IgE antibody, which plays a crucial role in immediate-type (i.e., Type I) allergic reactions to food, is usually not involved in adverse reactions caused by food additives.

Skin prick tests and allergy blood tests are not helpful in identifying the food additive culprit in most cases.  Careful observation and maintaining food and symptom diaries are sometimes useful in narrowing down the offending additive. Oral challenges under close monitoring in controlled environments may be needed to arrive at a specific diagnosis.


Avoidance of the suspected food additive is the only certain way of preventing adverse effects.  One should be vigilant about reading food labels and asking restaurants about ingredients and cooking methods.

If there is a history of anaphylaxis, carrying an epinephrine auto-injector (e.g., EpiPen, Auvi-Q, Adrenaclick) is extremely helpful in emergency treatment.  It is important to emphasize that if a self-injectable epinephrine device is used, one should go immediately to the closest emergency room.

The board certified allergy doctors at Black & Kletz Allergy have 3 locations in the Washington, Northern Virginia, and Maryland metropolitan area. We have offices in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA. Our 3 office locations have on-site parking and the Washington, DC and McLean, VA offices are Metro accessible. Our McLean office has a free shuttle that runs between our office and the Spring Hill metro station on the silver line. The allergy doctors at Black & Kletz Allergy diagnose and treat both adult and pediatric patients. To schedule an appointment, please call our office directly or alternatively, you can click Request an Appointment and we will respond within 24 hours by the next business day. The allergy doctors at Black & Kletz Allergy have been serving patients with food additive allergies, food allergies, hay fever (i.e., allergic rhinitis), asthma, sinus disease, hives, eczema, insect sting allergies, medication allergies, and immunological disorders for more than 50 years. If you are bothered from allergies, it is our mission to improve your quality of life by reducing or preventing your unwanted and bothersome allergy symptoms.

Pregnancy and Allergies


Asthma and allergies are quite common in pregnancy. Although complications from asthma and allergies are much less common, approximately 1% of pregnant women suffer from asthma during their pregnancy. Many more suffer from allergic rhinitis (i.e., hay fever) and other allergies (e.g., food, medication). Allergy symptoms due to allergies tend to be worse in pregnancy for approximately one-third of women, better in another one-third, and about the same as before pregnancy for the other one-third. It is important to note that it is also possible to develop new allergies during pregnancy.

Many women without a previous history of allergies complain of allergy symptoms during pregnancy. In some of these women, they indeed have developed allergies. In others, the allergy symptoms are present, but there is no definitive allergy. In these latter women, their elevated estrogen and progesterone levels are responsible for the typical nasal congestion that they may be experiencing. The increased hormone levels cause one’s mucus membranes to swell. When this swelling affects the nose, nasal congestion is the result. The diagnosis of hormone-induced nasal congestion of pregnancy is then justified if the hormonal elevation alone is responsible for the nasal congestion. Note that in addition to the nasal congestion, some nonallergic pregnant women who have hormone-induced nasal congestion of pregnancy may also experience a post-nasal drip and an associated cough due to the post-nasal drip.

The most common allergies during pregnancy are not any different than in non-pregnant women. Allergic rhinitis symptoms during pregnancy are still due to the same common allergens which usually include pollens, dust mites, molds, pets (e.g., cats, dogs), and cockroaches. The classic symptoms still may include sneezing, runny nose, itchy nose, nasal congestion, post-nasal drip, itchy throat, sinus congestion, sinus headaches, itchy eyes, watery eyes, puffy eyes, and/or redness of the eyes. In asthmatic individuals, wheezing, chest tightness, coughing, and/or shortness of breath may also occur. It should be emphasized that the lack of sneezing and itching in a pregnant woman with nasal congestion should be a red flag to consider a diagnosis of hormone-induced nasal congestion of pregnancy, as opposed to the classic allergic rhinitis in a pregnant individual.

The diagnosis of allergic rhinitis and/or asthma while pregnant begins with a comprehensive history and physical examination history performed by a board certified allergist, like the ones at Black & Kletz Allergy. Allergy blood tests may be ordered to diagnose a pregnant patient. Allergy skin testing is generally not performed on pregnant women.

Once the diagnosis is made, the focus turns to treatment. Treatment of allergic pregnant women is similar to non-pregnant women however the medications used to treat pregnant women are more limited. Only medications that have a Category B pregnancy rating and occasionally a Category C pregnancy rating (if needed) are generally used. There are antihistamines, nasal sprays, leukotriene antagonists, and asthma inhalers that are Category B which are utilized first in the treatment of allergic rhinitis and asthma. Most of the time, improvement can be obtained by using just Category B pregnancy medications. Pregnant women should be cautious before using any medication while pregnant, particularly during the first trimester. Pregnant women should get approval from their Ob/Gyn physician before using any medication, even if prescribed by another physician.

Allergy immunotherapy (i.e., allergy shots, allergy injections, allergy desensitization, allergy hyposensitization) can be continued in pregnant women. Individuals however are not started on allergy immunotherapy if one is already pregnant.

One other important caveat regarding the treating allergies in both allergic and nonallergic patients is the concept of avoidance. It is always recommended to avoid the offending allergen whether it is in the environment (e.g., pollens, molds, dust mites, pets), in the food (e.g., peanuts, shellfish, nuts, fish), or anywhere else. Avoiding what one is allergic to is always the best alternative if possible.

The board certified allergists at Black & Kletz Allergy have been treating pregnant and lactating women for many years. Black &Kletz Allergy has 3 convenient locations in the Washington, DC, Northern Virginia, and Maryland metropolitan area. We have offices in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA which all offer on-site parking. The Washington, DC and McLean, VA locations are Metro assessable. We offer a free shuttle that runs between our McLean, VA office and the Spring Hill metro station on the silver line. Please call us to schedule an appointment or you can click Request an Appointment and we will reply within 24 hours by the next business day. The allergy specialists of Black & Kletz Allergy are eager to help you with your allergy, asthma, and immunology needs. We are dedicated to providing exceptional care and service to you as we have been doing in the Washington, DC metro area for more than 50 years.