Rooting Out CRS Causes Is Cause for Debate

Dr. Ponikau examined several types of fungi, but Alternaria produced the most significant effects. All the other fungi didn’t really matter, he said. It was really a signal that was coming out of Alternaria which was doing that.

Antifungal medications have shown promise in treating chronic rhinosinusitis patients. In a small study including 10 patients taking amphotericin B, an antifungal, and 14 control subjects, those with the disease showed a 10% reduction in nasal blockage, according to CT scans. The control group showed hardly any change. When the same groups were examined using an endoscope, the amphotericin B group showed much better results than a placebo group, after both three months and six months.

Further studies have shown that IL-5 levels were reduced in patients taking amphotericin B.

In a larger study of amphotericin B’s effects, on 299 chronic rhinosinusitis patients, the primary endpoint-complete clearance of congestion and the total loss of headache-was not met. But Dr. Ponikau said that the study still showed promise because of the effects that could be seen in those patients with more severe symptoms.

When you slice this trial apart, it was interesting that, if you look at the patients who had more severe intense inflammation, the trial becomes significant in improving the patients’ symptoms, he said. The more inflammation that they had, the better the antifungals would work.

The reason for the discrepancy was that in the patients with less severe symptoms, the effects of the lavage could not be distinguished from the effects of the drug. The problem, he said, was that there was actually a therapeutic effect of the lavage itself. And the antifungals were working better, but it was very difficult to overcome that therapeutic effect.

Evidence for Bacterial Causes

Dr. Kern expressed doubts that fungi play as critical a role in chronic rhinosinusitis as Dr. Ponikau suggested, pointing instead to studies highlighting the role of bacteria.If you look at the microbiology of CRS, you can look at a number of studies that suggest that staph are disproportionately present in CRS patients with nasal polyps, as opposed to controls, he said, although he acknowledged that fungi are present as well.

The research group at Northwestern isolated staphylococcal toxins in polypoid sinusitis and found evidence of a characteristic T-cell response to those toxins in polyp tissues. There is a fingerprint of the staph effect, Dr. Kern said. The fingerprint is seen in about half of the cases. Nevertheless, this fingerprint is definitely there. The staph effect can be seen.