ORLANDO, FL-Eosinophils are the bane of nasal mucosa, and no one knows better than Fredrick A. Kuhn, MD, of the Georgia Nasal and Sinus Institute in Savannah, GA-a region where it is not uncommon for otolaryngologists to see patients presenting with polyps. At the ARS section of the recent annual Combined Otolaryngology Spring Meeting, he described the role eosinophils play in polyps and inflammatory sinusitis.
Sinus inflammation is due to the release of eosinophilic inflammatory mediators from the cytoplasmic granules in eosinophils. In sinus disease, the primary problem is the recruitment of the eosinophils to the sinus wound. The secondary problem then is what the eosinophils do to the sinus mucous membrane after they release their inflammatory mediators. They do this in the quest to destroy some offending invading organism, he said.
Once inflammatory mediators are in the sinus mucosa, they can induce tissue damage, edema, the production of sticky thick mucus, and polyp formation.
Although surgery is an important part of managing polyps, it’s not the key form of managing the problem, and postoperative management is hugely important.
We begin oral steroids when we discharge the patient from the hospital; we continue them until the patient is healed and at stage zero. And then we choose some alternate medical management plan to switch the patient over to, and taper them off their steroids, he said.
There is no ideal way of removing polyps-they all bleed. Vasodilation effects of anesthetic gas and mucosal inflammation don’t help, but they cannot readily be changed. For one, anesthesiologists aren’t likely to change how they do things, and as for controlling inflammation, steroids don’t always work.
One could try to reduce the eosinophilic mediators, but this is problematic because if we really treat the patient well, we may end up missing the diagnosis-and that is either finding the eosinophils in tissue and mucus or perhaps not finding the fungus, he said.
For surgery, Dr. Kuhn’s center used a KTP laser from 1985 to 1993. It works great-it coagulates the tissue and cuts it off, and you don’t get any bleeding. But it is unbelievably slow, he said. Radiofrequency debrider blades were effective, too, but they clog easily, the contacts get covered with char…there is thermal injury, and it’s relatively slow, he said.
Recently, Dr. Kuhn has tried using coblation, with an instrument that has been modified by the manufacturer to fit into the nose. He described using the device on a patient who underwent a bilateral procedure: One side was treated with the coblation device, the other using a standard technique. We did the right side without the coblation device, and used a debrider. We lost between two and 400 cc’s of blood doing the ethmoidectomy. On the left side, we used the coblation device, and we had zero blood loss….I think that this is something that’s kind of exciting and has some promise for taking polyps out of the ethmoid, he said.
Postsurgery Management and Mucosal Staging
Medical management of patients postsurgery is vital, and is the hard part, Dr. Kuhn said. His key words of advice were, Use long-term regular office follow-up with nasal endoscopy-that’s an absolute must. In his own practice, patients are followed monthly for a year, then, if they are doing well, every second month. If the inflammation stays low, then follow-up visits can slowly become further apart.
Importantly, the mucous membrane is staged at each visit. We culture secretions whenever they’re present, because the underlying problem with a lot of these polyps and their recurrence is subsequent infection, he said.
There are four stages used in a system Dr. Kuhn helped develop for this. Stage 0 is no evidence of disease; Stage 1 is beginning edema; Stage 2 is the development of polypoid edema; and Stage 3 is the recurrence of polyps.
Allergic Fungal Sinusitis
One type of eosinophilic inflammatory sinusitis is due to allergic fungal sinusitis (AFS). The major criteria for diagnosing AFS are Type 1 hypersensitivity, polyps, a characteristic CT scan, eosinophilic mucus, and a positive fungal smear.
However, patients who have previously undergone polyp surgery and present with AFS will not have a characteristic CT scan-and the diagnosis becomes more difficult, Dr. Kuhn said. These patients will meet the other criteria for AFS, though.
In general, AFS patients can be managed with a tapered regimen of oral prednisone until they reach Stage 0. After that they can be switched to other treatment modalities. Bursts and tapers of prednisone can be used for recurrence, and lesser disease may respond to only two or three cycles. Topical steroids can also be used, via irrigation or other modalities. Dr. Kuhn reported that in his experience, montelukast (Singulair) has not been very useful for this condition, but has had some minor success with nonsteroidal anti-inflammatory drugs
Eosinophilic inflammatory sinusitis is a chronic problem with no obvious cure, and it does not always have an obvious etiology. Consider, for instance, cases that appear to be AFS, but no fungus can be found. These patients generally meet three of the five criteria: Type-1 hypersensitivity, polyps, and eosinophilic mucus.
We believe the patients’ systems have become upregulated to the point that they have learned how to recruit eosinophils to the sinus wound, he said. There has been some suggestion that keeping infections under control may, over time, reduce eosinophil recruitment. I believe that if we can keep their infections under control for a lengthy period of time, perhaps their system downregulates in its willingness or ability to recruit eosinophils to the sinus lamina, he said.
What we’re dealing with is not really a disease in the true sense of the word. Nor is it an infection, Dr. Kuhn said. It is the result of eosinophilic-mediated inflammation. Possibly, it is infection-mediated (or maybe this is the case in some patients) by some sort of superantigen. In some cases, Type 1 hypersensitivity maybe involved in eosinophil recruitment. Patients may have a genetic predisposition to this problem, too.
Still, it is important to listen to patients. Think about what you see. And ask why things are the way they are. And then what is it that you possibly can do to change it. And if you do that, then I think you will progress in your knowledge and your ability to take care of your patients, he said.
©2008 The Triological Society