Chronic Sinusitis: Comparison of Amoxicillin Concentration in Diseased versus Normal Mucosa

Abstract

Despite advances in diagnostic and treatment strategies, chronic sinusitis remains both a common entity and a difficult disease to eradicate. Current medical management, which consists primarily of extended antibiotic therapy, is effective in temporarily alleviating symptoms, but is ineffective in a number of patients in eradicating the infection. One hypothesis for the failure of medical management may be due in part to inadequate penetration of antimicrobials into the diseased sinus mucosa. In order to investigate this, mucosal specimens consisting of nasal polyps and/or diseased anterior ethmoid mucosa were harvested from 19 patients with chronic sinusitis who were being treated with Augmentin® and analyzed for amoxicillin concentrations by high pressure liquid chromatography. A biopsy of normal-appearing mucosa from the inferior turbinate was obtained from the same patient and served as the control, and was analyzed for amoxicillin concentration. Nine of 14 (64%) patients who had polyps harvested had amoxicillin concentrations in the polyps less than the amoxicillin concentration in the inferior turbinate. Two of the 14 (14%) patients had amoxicillin concentrations in the polyps greater than the amoxicillin concentration in the inferior turbinate, and the remaining three patients had amoxicillin concentrations in the polyps similar to the amoxicillin concentration in the inferior turbinate, (P = 0.029). Five of the 10 (50%) patients who had diseased anterior ethmoid sinus mucosa had amoxicillin concentrations in the diseased anterior ethmoid sinus less than the amoxicillin concentration in the inferior turbinate. Two of the 10 (20%) patients had similar amoxicillin concentrations in the diseased anterior ethmoid sinus and in the inferior turbinate and three of 10 (30%) patients with diseased anterior ethmoid sinus mucosa had amoxicillin concentrations greater than the amoxicillin concentration in the inferior turbinate. (P = 0.3725). These data suggest that there is impaired penetration of amoxicillin into nasal polyps and possibly a trend toward impaired penetration of amoxicillin into diseased anterior ethmoid sinus mucosa.