Chronic sinus infection & fungi

Townsend Letter for Doctors and Patients,  Nov, 2005  by Jule Klotter

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Mayo Clinic scientists have found a connection between chronic rhinosinusitis (CRS) and a person's response to common airborne fungal spores. Their research is shifting attention away from the bacterial infections that characterize CRS and towards underlying inflammation. The scientists found spores from Alternaria, Aspergillus, Penicillium, and Cladosporium in the upper airway secretions belonging to healthy people as well as those with chronic sinusitis. People with CRS, however, "show exaggerated humoral and cellular responses ... to common airborne fungi, particularly Alternaria." Alternaria, whose spore is larger than the other fungi, has been associated with asthma in several countries.

In a December 2004 study, scientists took blood samples from 18 patients with CRS and 15 normal individuals and looked for cellular and humoral immune responses to airborne fungi. Although all serum samples had IgG antibodies to the fungi, people with CRS had higher levels: "The median serum IgG antibody level to Alternaria was about 5-fold higher for patients with CRS." IgE antibodies to the fungi, however, appeared in less than 30% of those with CRS. Cell cultures showed that about 90% of people with CRS produced the cytokines IL-5 and IL-13 when exposed to Alternaria. In addition, cells from people with CRS responded to Alternaria with significantly more IFN-[greater than or equal to] than cells from normal people did. The scientists also collected nasal secretions from nine additional patients and nine controls and checked the samples for fungal proteins and inflammatory mediators. All of the samples from the CRS group showed "markedly elevated levels of eosinophil [major basic protein] (4093 [+ or -] 878 mg/mL, mean [+ or -] SEM) and IL-5 (226 [+ or -] 69 pg/mL) compared with the undetectable levels in secretions from 9 other normal individuals (P = .0003 and .0092, respectively)."

In a later study, published in Journal of Allergy and Clinical Immunology (August 2005), Mayo Clinic scientists reported that the nasal and sinus mucus taken from people with CRS contains activated white blood cells (eosinophils) that produce a toxic protein (Major Basic Protein). Although Major Basic Protein was not found in the tissue itself, levels in the mucus "far exceeded that needed to damage the nasal and sinus membranes and make them more susceptible to infections such as chronic sinus infection." Mayo Clinic ear, nose and throat specialist Jens Ponikau, MD, stated in a Mayo Clinic news release that "some surgeons have already started to change the way they do surgery for patients with chronic sinus infections, focusing now on removing the mucus, which is loaded with toxins from the inflammatory cells, rather than the tissue during surgery."

Chronic Sinus Infection Thought to Be Tissue Issue, Mayo Clinic Scientists Show It's Snot. www.mayoclinic.org 28 July 2005

Shin, Seung-Heon, MD et al. Chronic rhinosinusitis: An enhanced immune response to ubiquitous airborne fungi. J Allergy Clin Immunol December 2004

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