The Effect of Injection Immunotherapy on Mucociliary Clearance in Allergic Patients Ryan C. Cmejrek, MD, a Michael T. Gutman, MD, a Augusto J. Torres, MD, a Kevin J. Keen, PhD, PStat, a,b,c Steven M. Houser, MD, FAAOA, FARS, FACS a a From the MetroHealth Medical Center, University Hospitals of Cleveland, and the b Department of Epidemiology and Biostatistics, Case Western Reserve University, and c University of Northern British Columbia. OBJECTIVE: To assess the effect of injection immunotherapy on mucociliary clearance in allergic patients with the use of the saccharin test. METHODS: In this prospective cohort study, mucociliary clear- ance in 42 allergic patients treated with injection immunotherapy was determined with the saccharin test. Of these patients, 23 were retested 1 year later to assess changes in mucociliary clearance times. Mean results for historical controls were determined in a review and meta-analysis of the existing literature. RESULTS: Saccharin clearance times (SCTs) were initially pro- longed in allergic patients who received injection immunotherapy when compared to historical controls (one-sided P value  0.05). However, after 1 year of immunotherapy, there was a significant reduction in SCTs in our patient population. This finding was independent of other evaluated patient characteristics, with the exception of nasal steroid use, which was also significantly asso- ciated with a decrease in SCT. CONCLUSIONS: After 1 year of injection immunotherapy, there was a significant reduction in mean SCT in our patient population. Of the other factors studied, only nasal steroid was associated with decreased mucociliary clearance times. To our knowledge, this is the first report in the literature documenting the beneficial effect of injec- tion immunotherapy on mucociliary clearance as measured by sac- charin clearance times. Nevertheless, further research is warranted, given the confounding effect of nasal steroid use. © 2005 American Academy of Otolaryngology–Head and Neck Sur- gery Foundation, Inc. All rights reserved. M ucociliary clearance is a primary function of the up- per airway. This process is an important aspect of the first-line defense against infecting organisms, antigens, and debris. Mucus that lines the nasal cavity acts to trap inhaled particles. The trapped particles are then transported by a coordinated action of cilia toward the nasopharynx where they are swallowed or expectorated. This process of trans- port is complex and dependent upon ciliary function and the rheologic properties of mucus. Alterations in either can lead to ineffective mucociliary flow. There are a number of ways to measure mucociliary clearance. Although the gold standard for measurement of mucociliary clearance is the radiolabeled method, 1 a sim- pler, safer, and efficacious alternative is the saccharin test. 2 Saccharin clearance time (SCT) has been documented in the literature to assess mucociliary clearance in normal subjects as well as in those with various sinonasal disorders, such as allergic rhinitis (AR) and chronic rhinosinusitis. 3-5 However, mucociliary clearance in allergic patients un- dergoing injection immunotherapy has not been studied by SCT or by any other method (MEDLINE search, 1966- present). In addition, factors that might alter mucociliary clearance in these patients, such as length of immunother- apy, antihistamine and nasal steroid use, history of sinonasal surgery, and tobacco use, have not been fully elucidated. Whether symptomatology and SCT are associated in these patients is unknown. Presented at the Middle/Southern Section Meeting of the Triological Society, Marco Island, Florida, January 8-11, 2004. Reprint requests: Ryan C. Cmejrek, Case Western Reserve University, University Hospitals of Cleveland, Department of Otolaryngology–Head and Neck Surgery, 11100 Euclid Ave, Cleveland, OH 44106. E-mail address: rcc4@alumni.case.edu. Otolaryngology–Head and Neck Surgery (2005) 133, 9-15 0194-5998/$30.00 © 2005 American Academy of Otolaryngology–Head and Neck Surgery Foundation, Inc. All rights reserved. doi:10.1016/j.otohns.2005.03.062