Memorial Day Hours

Please note: due to the Memorial Day holiday, we will be closed on Monday (5/30/11), and are adding extra allergy shot hours on Tuesday 9-12:45 and 2-4:45.

Chronic Hives and High Blood Pressure

A recent study found that the duration of hives was significantly longer in patients with high blood pressure that is not adequately controlled. This finding had nothing to do with the medications being used to treat hypertension. It has not yet been determined whether or not adequate treatment of high blood pressure will result in improved management of hives.

Take home message: For those patients who have chronic hives and are also being treated for high blood pressure, check with your family doctor to see if your hypertension is well controlled.

Scombroid Poisoning Masquerading as a Fish Allergy

Tuna and mackerel belong to the Scombridae family of fish. These fish naturally contain a high level of the chemical, Histidine. It turns out that a bacteria in inadequately refrigerated fish (not limited to this family of fish) is able to convert Histidine to Histamine, the chemical that all allergy sufferers want to avoid like the plague. Histamine is released in large quantities in people who have hay fever, allergic asthma, and allergic hives; it is, in large part, responsible for the allergic symptoms that occur with exposure to a specific trigger. Patients with scombroid poisoning develop allergy-like symptoms within an hour of eating "bad" fish: flushing, hives, gastrointestinal discomfort, and shortness of breath. There are tests available to distinguish "poisoning" from "allergy."  Immediate medical attention should be sought if these symptoms occur.

Take home message: Seared Ahi Tuna sandwiches do not have to be avoided for life if you have been "poisoned." Scombroid poisoning can masquerade as a fish allergy and fool people into a life-long avoidance of their favorite food.

Could ladybugs or cockroaches be causing your allergic respiratory symptoms?

Home infestations with ladybugs (Harmonia axyridis) occur throughout the U.S.   During a screening of blood bank donors,  about 10% had evidence of allergy to ladybug.  However, the test used may not always distinguish between ladybug and cockroach specific allergy antibodies.  A skin test using ladybug extracts was more successful in distinguishing the two, but is not commercially available at this point.

Cockroach allergy is quite common, especially in urban areas where people are more likely to be exposed to cockroaches in the home as well as in public buildings.  Cockroach exposure can trigger a sensitized person to have a major asthma attack or nasal allergy symptoms.  Now we should also consider the possibility of ladybug sensitization as a cause of similar symptoms.

Ann Allergy Asthma Immunol 2009 Nov; 103(5): 432-5.  Clark MT, Levin T, Dolen W.  Cross-reactivity between cockroach and ladybug using the radioallergosorbent test.

Ann Allergy Asthma Immunol 2010 Aug; 105(2): 182-3. Goetz DW. Clinical efficacy of asian ladybug whole-body extract skin testing.

Latex Allergies

It has been a well recognized fact for years that many patients with a sensitivity to latex will experience allergic symptoms (hives, itching of the mouth & throat, swelling of the lips) following the ingestion of foods that share allergenic properties with latex. The most common foods on the list include: banana, chestnut, avocado, and mango. Passion fruit has now been added to the foods to be avoided list. A recent article in the allergy literature reported on a latex allergic woman who developed oral allergy symptoms after ingesting a soft drink containing passion fruit extract.

Take home message: Patients with latex allergy should avoid ingestion of passion fruit until testing is done.