Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
To diagnose food allergy, a doctor first must determine if the
patient is having an adverse reaction to specific foods. The doctor
makes this assessment with the help of a detailed history from the
patient, the patient's dietary diary, or an elimination diet. He or
she then confirms the diagnosis by the more objective skin tests,
blood tests, or food challenges.
History: The history usually is the most important diagnostic
tool in diagnosing food allergy. The physician interviews the patient to determine if the facts
are consistent with a food allergy. The doctor may ask the following questions:
What was the timing of the reaction? Did the reaction come on
quickly, usually within an hour after eating the food?
Was treatment for allergy successful? For example, if hives stem
from a food allergy, antihistamines should relieve them.
Is the reaction always associated with a certain food?
Did anyone else get sick? For example, if the person has eaten
fish contaminated with histamine, everyone who ate the fish should be
sick. In an allergic reaction, however, only the person allergic to
the fish becomes ill.
How much did the patient eat before experiencing a reaction? The
severity of the patient's reaction can sometimes relate to the amount
of the suspect food eaten.
How was the food prepared? Some people will have a violent
allergic reaction only to raw or undercooked fish. A thorough cooking
of the fish destroys those allergens in the fish to which they react,
so that they then can eat it with no allergic reaction.
Were other foods eaten at the same time as the food that caused
the allergic reaction? Fatty foods can delay digestion and thus delay
the onset of the allergic reaction.
Dietary diary: Sometimes, a history alone cannot determine the
diagnosis. In that situation, the doctor may ask the patient to keep
a record of the contents of each meal and whether reactions occurred
that are consistent with allergy. The dietary diary provides more
details than the oral history, so that the doctor and patient can
better determine if there is a consistent relationship between a food
and the allergic reactions.
Elimination diet: The next step that some doctors use is an
elimination diet. Under the doctor's direction, the patient does not
eat a food suspected of causing the allergy, for example, eggs, and
substitutes another food, in this instance, another source of
protein. If after the patient removes the food, the symptoms go away,
the doctor almost always can make a diagnosis of food allergy. If the
patient then resumes eating the food (still under the doctor's
direction) and the symptoms return, this sequence confirms the
diagnosis. The patient should not resume eating the food, however, if
the allergic reactions have been severe because this re-challenge is
too risky. This technique is also not suitable if the allergic
reactions have been infrequent.
If the patient's history, dietary diary, or elimination diet
suggests that a specific food allergy is likely, the doctor then will
use tests, such as skin tests, blood tests, and a food challenge,
which can more objectively confirm an allergic response to food.
Skin tests: In a scratch-the-skin test, a dilute extract of the suspected food is placed on the skin of the forearm or back. This portion of the skin then is scratched with a needle and observed for swelling or redness, which would signify a local allergic reaction to the food. A positive scratch test indicates that the patient has the IgE antibody that is specific for the food being tested on the skin's mast cells. Skin tests are rapid, simple, and relatively safe.
A person can have a positive skin test to a food allergen, however, without experiencing allergic reactions to that food. A doctor diagnoses a food allergy only when the patient has a positive skin test to a specific allergen and the history suggests an allergic reaction to the same food. In some highly allergic people, however, especially if they have had anaphylactic reactions, skin tests should not be done because they could provoke another dangerous reaction. Skin tests also cannot be done in patients with extensive eczema.
Blood tests: In those situations where skin tests cannot be done, a doctor may use blood tests such as the RAST and the ELISA. These tests measure the presence of food-specific IgE antibodies in the blood of patients, but they cost more than skin tests, and the results are not available immediately. As with positive skin tests, positive blood tests make the diagnosis of a specific food allergy only when the clinical history is compatible.
Food challenge: The double-blind food challenge has become the gold standard for objective allergy testing. (Some physicians prefer the term double-masked, rather than double-blind.) In this test, various foods, some of which are suspected of inducing an allergic reaction, are placed in individual opaque capsules. Both the patient and the doctor are blinded, so that neither of them knows which capsules contain the suspected allergens. (The capsules are prepared by another medical worker.) The patient swallows a capsule and the doctor then observes whether an allergic reaction occurs. This process is repeated with each capsule. Alternatively, the food to be tested may be disguised in another type of food to which the person is not allergic.
The advantage of a food challenge is that if the patient has an allergic reaction only to the suspected foods and not to the other foods tested, the diagnosis of food allergy is confirmed. Just as with a re-challenge after the elimination diet and with the skin tests, however, someone having a history of severe reactions should not be tested with a food challenge because of the danger of inducing another severe reaction. In addition, this procedure is expensive because it is difficult and requires a lot of time, especially for patients with multiple food allergies. This type of test must also be done under the careful supervision of a physician. Consequently, double-blind food challenges are done infrequently. They are done most commonly, however, when the doctor wishes to obtain evidence to confirm the suspicion that the patient's symptoms are not due to a food allergy. Then, additional efforts may be directed at finding the real cause of the patient's symptoms.
Abdominal pain is pain in the belly and can be acute or chronic. Causes include inflammation, distention of an organ, and loss of the blood supply to an organ. Abdominal pain can reflect a major problem with one of the organs in the abdomen such as the appendix, gallbladder, large and small intestine, pancreas, liver, colon, duodenum, and spleen.
Eczema, also known as dermatitis, is a general term for many types of skin inflammation. The most common form of eczema is atopic dermatitis. The other forms of eczema include: contact eczema, seborrheic eczema, Nummular eczema, Neurodermatitis, stasis dermatitis, and dyshidrotic eczema. Symptoms, diagnosis, and treatment of eczema may vary from person to person and may depend on the type of eczema.
Diarrhea is a change is the frequency and looseness of bowel movements. Cramping, abdominal pain, and the sensation of rectal urgency are all symptoms of diarrhea. Absorbents and anti-motility medications are used to treat diarrhea.
Rheumatoid arthritis is an autoimmune disease that causes chronic inflammation of the joints, the tissue around the joints, as well as other organs in the body. Because it can affect multiple other organs of the body, rheumatoid arthritis is referred to as a systemic illness and is sometimes called rheumatoid disease.
Migraine is usually periodic attacks of headaches on one or both sides of the head. These may be accompanied by nausea, vomiting, increased sensitivity of the eyes to light (photophobia), increased sensitivity to sound (phonophobia), dizziness, blurred vision, cognitive disturbances, and other symptoms. Treatments for migraine headache include therapies that may or may not involve medications.
Hives, also called urticaria, is a raised, itchy area of skin that is usually a sign of an
allergic reaction. The allergy may be to food or medications, but usually the
cause of the allergy (the allergen) is unknown.
Nausea is an uneasiness of the stomach that often precedes vomiting. Nausea and vomiting are not diseases, but they are symptoms of many conditions. The causes of vomiting differ according to age, and treatment depends upon the cause of nausea and vomiting.
Itching can be a common problem. Itches can be localized or generalized. There are many causes of itching to include: infection (jock itch, vaginal itch), disease (hyperthyroidism, liver or kidney), reactions to drugs, and skin infestations (pubic or body lice). Treatment for itching varies depending on the cause of the itch.
Osteoarthritis is a type of arthritis caused by inflammation, breakdown, and eventual loss of
cartilage in the joints. Also known as degenerative arthritis. Osteoarthritis
can be caused by aging, heredity, and injury from trauma or disease.
In lactose intolerance, the digestive system cannot digest lactose (the main sugar in milk). Symptoms of lactose intolerance include diarrhea, flatulence, abdominal pain, abdominal bloating, abdominal distention, and nausea. There are several tests to diagnose lactose intolerance. Treatment is generally made with dietary changes, supplements, and adaptation to small amounts of milk.
Celiac disease is a result of an immune reaction to gluten, a protein found in wheat or related grains and present in many foods that we eat. Celiac disease causes impaired absorption and digestion of nutrients through the small intestine. Signs and symptoms of celiac disease include malabsorbption (diarrhea, foul smelling gas, bloating, and increased amounts of fat in the stool) and malnutrition (weight loss, edema, anemia, bruising easily, neuropathy, and infertility). Treatment for celiac disease is a gluten free diet, and at times if necessary, medications
Food poisoning is common, but can also be life threatening. The most common form of food poisoning is caused by bacteria and include symptoms such as fever, abdominal pain, diarrhea, nausea and vomiting.
Asthma is a common disorder in which
chronic inflammation of the bronchial tubes (bronchi) makes them swell, narrowing the airways. Signs and symptoms include shortness of breath, chest tightness,
cough and wheezing.
Colic is crying or fussing that begins suddenly, lasting for a total of three hours a day and happening more than three days a week for about three weeks. Symptoms include the baby's face turning red, the belly is distended, the feet may be cold, the hands clenched, and the legs may alternate between being flexed or extended. Treatment may involve ruling out other causes of the fussing and the doctor prescribing anti-gas bubbly medicine.
An allergy refers to a misguided reaction by our immune system in response to bodily contact with certain foreign substances. When these allergens come in contact with the body, it causes the immune system to develop an allergic reaction in people who are allergic to it. It is estimated that 50 million North Americans are affected by allergic conditions. The parts of the body that are prone to react to allergies include the eyes, nose, lungs, skin, and stomach. Common allergic disorders include hay fever, asthma, allergic eyes, allergic eczema, hives, and allergic shock.
Anaphylaxis is a serious allergic reaction that affects a number of different areas of the body at one time, and can be fatal. Causes of anaphylaxis can be food allergy, latex allergy, allergy to insect or but stings/bites, asthma, or other materials or conditions. Symptoms include flushing, itching, hives, anxiety, rapid or irregular pulse. Severe symptoms may be throat and tongue swelling, swallowing, and difficulty breathing. Some disorders appear similar to anaphylaxis such as fainting, panic attacks, blood clots in the lungs, heart attacks, and septic shock. If you think that you may be having an anaphylactic reaction, seek emergency care or call 911 immedately.
It's important to know whether you will breastfeed or bottle-feed your baby prior to delivery, as the breasts' ability to produce milk diminishes soon after childbirth without the stimulation of breastfeeding. Breast milk is easily digested by babies and contains infection-fighting antibodies and cholesterol, which promotes brain growth. Formula-fed babies actually need to eat somewhat less often since formula is less readily digested by the baby than human milk. This article explores the advantages and disadvantages of both forms of feeding.
Occupational asthma is a type of asthma caused by exposure to a substance in the workplace. Symptoms and signs include wheezing, chest tightness, and shortness of breath. The usual treatment for occupational asthma involves removal from exposure and the use of bronchodilators and inhaled anti-inflammatory medicines.