Topical Probiotic Sinus Irrigations for Treating Chronic Sinusitis

Inclusion Criteria: 1. Male and female patients 18 years of age or older. 2. Patients diagnosed with acute exacerbation of CRS, defined by worsening of 1 or more sinonasal symptoms (nasal obstruction/congestion, nasal discharge, facial pain/pressure, reduced sense of smell) and inflammatory and/or infectious changes on sinus endoscopy. 3. Patients that have undergone functional endoscopic sinus surgery \> 12 months prior to enrollment as documented in the patients electronic medical record, with patent sinuses deemed suitable for trial on investigator's discretion. 4. Patients must be willing to follow study related procedures for the duration of the study. 5. Patients must understand the purpose and procedures and be willing to sign the study informed consent document. 6. All adult men and women with active CRS will be considered for participation in this study without regard to race, gender, or socioeconomic status. Exclusion Criteria: 1. Patients who are taking topical antibiotic irrigations and are unwilling to stop them. 2. Patients who are unable to complete self-administered questionnaires because of cognitive impairment, language barrier, or severe medical conditions. 3. Patients who have a terminal illness (malignancy), immunocompromised (medication-related immunosuppression, immunodeficiency disorder) or systemic disease (granulomatosis polyangiitis or other autoimmune disease with sinonasal manifestations, cystic fibrosis), or recent head/sinonasal trauma that may predispose to infectious complications. 4. Patients who have severe or emergent complications from CRS or presence of a sinus tumor. 5. Female patients who are pregnant or breastfeeding. The patient will be asked if she is pregnant or has any chance of being pregnant. In either case, the patient will be excluded. Note in our consent form this is also addressed (excerpt below). 6. Patients who are taking oral corticosteroids or who have taken oral antibiotics in the previous 2 weeks or on oral corticosteroids. 7. Patients who have upper respiratory infection-type symptoms at time of enrollment, e.g., fevers/chills, sneezing, runny nose, sore throat, coughing. Patients can be eligible for enrollment once symptoms have fully resolved if all other inclusion/exclusion criteria are met.