SAN DIEGO-Michael S. Morris, MD, believes that the everyday illnesses seen by community otolaryngologists should be better analyzed. Is it an allergy or an infection? Is it a bug? We should find out, he said.
A private practice otolaryngologist in Rockville, Maryland, Dr. Morris is also Clinical Associate Professor of Otolaryngology-Head and Neck Surgery and Family Medicine at Georgetown University Hospital. An advocate of more research by community physicians-the ones on the front line of common maladies-he encouraged Georgetown University medical student Akshay M. Mehta to join him in a study of 228 patients with upper respiratory tract infections, some of whom also suffered from allergies.
The result? The two found that allergy status is significantly correlated with bacterial infection and allergic patients have a higher rate of infection than those without allergies. In addition, women had the greatest rates of infection, particularly when compounded with a positive allergy profile.
Their study was presented by Mr. Mehta during the Triological Society’s April 28 program at the Combined Otolaryngology Spring Meeting (COSM). He noted that the highest incidences of bacterial infection were due to Staphylococcus aureus, but causality cannot be ascertained without insight into the basic pathologic mechanisms of allergy and its effects on the upper respiratory tract.
It’s simple stuff, not rocket science, Dr. Morris noted. We conducted an empirical observation supported by a careful review of 228 patients with clinical as well as laboratory documentation of what was wrong. What’s so surprising-maybe not so surprising-is that no one else has ever reported this.
Influence of Allergy on Pathogen Selectivity
Noting that upper respiratory infection and allergy are the most prevalent and challenging aspects of outpatient medicine and contribute to difficulty in determining treatment algorithms, Mr. Mehta and Dr. Morris studied the influence of allergy on pathogen selectivity in patients’ nasal cultures over a one-year period. The men, women, and children had presented with complaints of chronic sinusitis, chronic otitis media, pharyngitis, and chronic and recurrent allergy symptoms involving the head and neck.
Allergy testing was carried out with ImmunoCAP IgE quantification for specific airborne and food allergies. The researchers noted that this testing method is more sensitive and specific than previous RAST methodology and allows IgE quantification for individual allergens. The resulting allergy profiles were classified into six groups according to their quantified IgE levels.
Of the 228 patient cultures, 80 (35.08%) were positive for bacterial infection, with 42.5% of these S. aureus and 17.5% S. pneumoniae. In addition, 62.5% were also positive for allergies. Forty-six percent of those testing positive for both allergy and infection tested positively for S. aureus.
This verifies the previous hypothesis that allergic disease is a predisposition to acquiring a bacterial infection, Mr. Mehta said.
The researchers also noted that patients with a negative allergy profile had a different pathogen prevalence rate, with only 11% S. aureus, an increased incidence of S. pneumoniae (5%), and an increased incidence of infection by other uncommon pathogens.
Female patients with positive infection and positive allergy profiles had an even higher incidence of S. aureus infection-64%, Mr. Mehta said.
The study authors noted that successful treatment of allergic disease might reduce the dependency on chronic use of anti-inflammatory steroid use, decongestants, and especially empirical antibiotic therapy, thereby helping to delay the occurrence and development of antibiotic-resistant organisms.
Because of this study, if a male patient with a cold comes to visit me and he doesn’t have allergies, I’m now more inclined to treat him with symptomatic relief, not antibiotics, Dr. Morris said. If a woman with a cold comes in, and she takes allergy medicine, I’m more likely to think she’s got a bacterial infection.
The bottom line, according to Dr. Morris, is to better differentiate patients empirically and to be more fact-oriented in choosing therapies. Take time to do a culture. Be more certain of what you’re treating, he said.
©2007 The Triological Society