Saccharin test: Methodological validation and systematic review of the literature

Abstract

Objectives Saccharin test (ST) is a convenient method to assess the efficiency of mucociliary clearance, the primary defense mechanism of the upper airways’ tract. The study objectives are to: (1) substantiate its short- (3 days) and long-term (30 days) repeatability; (2) assess its tolerability; (3) conduct a systematic literature review and to compare our results with the existing evidence. Methods Twenty-nine healthy subjects were enrolled in an observational prospective study to perform an ST on three separate visits (at baseline; at follow-up visits at day 3 and at day 30). Transit times were recorded and self-reported nasal and general symptoms noted. A systematic review of the literature was conducted to compare our results with the existing literature. Results The mean values (±SD) of ST transit time (STTT) were 7.085 (±2.19), 7.788 (±2.11), and 7.790 (±2.06) minutes at baseline, day 3, and day 30, respectively. Significant linear regression analysis was observed between day 3 and baseline ( r = .193; P = .019) and day 30 and baseline ( r = .182 P = .024). Significant agreement for the intrasession repeatability was observed with an ICC = .354 ( P = .001). Outcomes’ comparisons between baseline vs day 3 ( P = .197) and baseline vs day 30 ( P = .173) were not statistically significant. ST was well tolerated. Concordance with existing literature’s data and high level of STTT repeatability were confirmed by the qualitative analysis. Conclusion STTT reproducibility was good both in the short- and long-term. ST tolerability was very good. Our study data are consistent with the existing literature, indicating ST as a sound methodology for detection of early respiratory health changes and for specific regulatory application in respiratory research.

Nasal mucociliary clearance after extremely low frequency by scintigraphic and histopathologic evaluation

“…The nasal MCC can be assessed by various in vitro techniques such as stroboscopy and photograph-electron technique, but they are overpriced and inappropriate for clinical routine studies or by in vivo techniques, using the particles such as saccharin, dye tests, radiopaque discs of teflon, and radiopharmaceuticals placed on the inferior turbinate and the time taken to reach the nasopharynx are measured. [21][22][23][24][25][26] In the literature, the saccharin test is frequently used to evaluate nasal MCC as it is non-invasive, well-tolerated, inexpensive, reproducible, and easily applicable. 23 However, its disadvantage is that NMTR cannot be measured directly and the finding of the test is totally dependent on the patient's subjective sense of taste.…”

“…[21][22][23][24][25][26] In the literature, the saccharin test is frequently used to evaluate nasal MCC as it is non-invasive, well-tolerated, inexpensive, reproducible, and easily applicable. 23 However, its disadvantage is that NMTR cannot be measured directly and the finding of the test is totally dependent on the patient's subjective sense of taste. On the other hand, the scintigraphic method can provide quantitative measurements as well as qualitative measurements that can be utilized in the evaluation of nasal MCC enabling the preclinical studies.…”

Upper Airway Mucociliary Clearance is Impaired in Dyspneic COVID-19 Patients

“…The following data were collected: age, smoking status, presence of rhinitis, presence or absence of symptomatic disease, and symptoms (cough, sore throat, nasal obstruction, runny nose, impaired taste or dysgeusia, loss of smell, dyspnea and headache). All individuals, except those who had dysgeusia, performed the saccharin test to assess the efficiency of mucociliary clearance [ 12 ].…”

Orally administered Chinese herbal therapy to assist post-surgical recovery for chronic rhinosinusitis—A systematic review and meta-analysis

“…Were Sino-Nasal Outcome Test (SNOT), including SNOT20 [ 57 ], SNOT22 [ 58 ] and SNOT8 [ 59 ], visual analogue scale for total nasal symptoms (VAS-TNS) and/or VAS for individual symptoms (VAS-IS), Lund-Mackay computed tomography score (LM) [ 60 ], Lund-Kennedy endoscopic score (LK) [ 61 , 62 ], Mucociliary transport time (MTT) [ 63 ], Mucociliary transport rate (MTR), Mucociliary clearance as percentage (MC), and adverse events (AEs) [ 64 ]. Effective rate scales not used internationally, and measures developed by the authors were excluded.…”