Evaluation and testing for better health

Are you allergic to penicillin? If so, are you sure about that? It’s surprisingly common for people to wrongly think they have a penicillin allergy – and that misconception can be dangerous for their health.

Ten percent of all patients in the United States claim to have a penicillin allergy. Of those, 90 percent are not truly allergic and can tolerate the drug. That means millions of people take alternative antibiotics, which are more expensive and can put their health and potentially the health of others at risk. The solution can be as easy as a simple allergy test.

Why would somebody be labeled as allergic to penicillin when they most likely are not? First, actual penicillin allergy diminishes or resolves within 10 years of the original reaction for 90 percent of patients. Secondly, penicillin allergy may be misdiagnosed after patients break out in a rash, as many rashes are actually due to the bacterial or viral infection itself. Sometimes side effects (for example, diarrhea or upset stomach) to penicillin mistakenly are recalled as penicillin allergies.

It is important to clarify an individual’s penicillin allergy status for several reasons.

Often, a “-cillin” antibiotic is the best choice for certain illnesses, particularly severe infections needing intravenous antibiotics, and unfortunately, testing cannot be accomplished when one is acutely ill. More and more infections are becoming “resistant” to our standard antibiotics, so it is important to have a larger choice available.

Another surprising statistic is that hospitalized patients with penicillin allergy on their record had more complications, lengthier hospital stays and higher costs. Additionally, those with documented penicillin allergies have much greater odds of developing a surgical site infection or experiencing an adverse event.

A study in the British Medical Journal looked at six years’ worth of medical records for patients in the United Kingdom and found that those with a penicillin allergy had an almost 70 percent greater chance of acquiring a methicillin-resistant Staphylococcus aureus (MRSA) infection and a 26 percent increased risk of Clostridium difficile-related colitis (C. diff.). MRSA and C. diff. are significant health risks worldwide. The study compared adults with a known penicillin allergy to similar people without a known penicillin allergy.

People labeled with a penicillin allergy are usually instead given broadspectrum antibiotics, which may kill off more good bacteria along with the bad. This appeared to increase a patient’s risk of infection with MRSA or C. diff., which are common in our environment and can live without causing any problems on someone’s skin or gut. However, if a broad antibiotic kills off competing good bacteria, MRSA and C. diff. can thrive and start to cause problems.

These problems also affect health-care costs, as demonstrated by data showing that a penicillin allergy label translated into an average increased cost of $1,145 to $4,254 per patient for outpatient and inpatient drug costs and inpatient hospitalizations.

How does one go about starting this pathway to better health? Some community allergists offer penicillin evaluation and testing. If your insurance doesn’t require a referral to a specialist, you can call and make an appointment. At the first visit, a careful medical history will be taken, acknowledging that the reaction may have been years or decades ago. It is important to remember as many details as you can, so if you were a child when you reacted, it would help if you talked to your parents about the reaction history before the appointment.

If the history suggests a possibility of an allergic reaction, we will arrange a testing visit to be able to officially disprove that the allergy is still present. We use the PRE-PEN test, which is the only FDA-approved skin test for the diagnosis of penicillin allergy. Penicillin skin testing involves applying skin prick and intradermal tests with PRE-PEN, Penicillin G, and both a positive and negative control, usually on the arm. After 20 minutes, the test sites will be examined for a reaction and, if negative, an oral challenge will be recommended.This involves ingesting divided doses of penicillin over the course of three to four hours while remaining in the doctor’s office, in case there is an adverse reaction or symptom that requires observation or treatment. The good news is that, of patients who undergo allergy testing and challenge, more than 98 percent can tolerate the medication. We compose a letter to your physicians and pharmacist acknowledging that you successfully completed penicillin testing and challenge, and advising them to change their records accordingly.

David Kaufman, M.D., is a board-certified asthma/ allergy/ immunology specialist at Breathe America, located in Ashley Ridge in Shreveport and Viking Drive in Bossier City. He is an assistant clinical professor of pediatrics at LSUHSC. Call 318-221-3584 or visit our website at www.breatheamerica.com to make an appointment, or to find more information on allergies and asthma.