Effect of commercial nasal steroid preparation on bacterial growth

Abstract

Background: Topical budesonide (Pulmicort; AstraZeneca AB, Sodertalje, Sweden) is commonly used in the management of chronic rhinosinusitis (CRS). Although its use is due to its perceived anti-inflammatory effect, studies have suggested that it may also have antibacterial properties. To make the hydrophobic steroid molecule suitable for topical administration, pharmaceutical excipients are used in commercial steroid formulations. Herein we investigated the antibacterial action of commercial budesonide and its excipients. Methods:Planktonic and biofilm forms of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) were treated with Pulmicort or its excipients at clinically relevant concentrations. Bacterial growth was determined by optical density, resazurin assays, colonyforming unit counts, and Giemsa staining. Minimum inhibitory concentration (MIC) studies assessed excipients' potentiation of antibiotics. Experiments were conducted in triplicate and results analyzed using one-way analysis of variance. Results:There was significant reduction in planktonic and biofilm growth of S aureus and MRSA on exposure to budesonide (p < 0.0001) and its excipients (p < 0.0001). Excipient ethylene diamine-tetraactic acid (EDTA) demonstrated an antibacterial property even at the low concentrations used in topical preparations (p < 0.0001). With amoxicillin, excipients exhibited a potential additive/synergistic effect on MIC, whereas erythromycin and aminoglycosides showed an antagonistic action. Conclusion:The commercial product Pulmicort has a direct antibacterial effect on the planktonic and biofilm forms of S aureus and MRSA. This effect is at least in part mediated through the excipient EDTA in the product. Excipients also influenced the antimicrobial activity of antibiotics depending on the bacterial strain and antibiotic tested. C 2019 ARS-AAOA, LLC.

Impact of ciprofloxacin impurities on bacterial growth, antibiotic resistance development and content assays

“…Additionally, the role of excipients on bacterial growth and resistance, which have been shown to influence antimicrobial activity of antibiotics (Cherian et al . 2019), should also be studied in more detail.…”

“…Measuring in vivo target site concentrations of poor-quality drugs that have low API, poor dissolution, and increased impurities and degradation products would also help inform clinical relevance. Additionally, the role of excipients on bacterial growth and resistance, which have been shown to influence antimicrobial activity of antibiotics (Cherian et al 2019), should also be studied in more detail.…”

Novel strategies for inhibition of bacterial biofilm in chronic rhinosinusitis

“…The results demonstrated a significant reduction in the growth of both planktonic and biofilm forms. Notably, EDTA showed an antibacterial effect in the topical application even at a low concentration, which could mediate the antibacterial effect of budesonide in low volume and high concentration in the topical application (Cherian et al, 2019). In another work, antibiofilm effects of topical corticosteroids were evaluated against bacteria recovered from CRSwNP patients.…”

“…Moreover, reduction of mucosal inflammation and decreased recurrence after surgery are other advantages of corticosteroids. However, the response of sinonasal bacteria to topical steroids is unknown (Cherian et al, 2019; Falkenstein et al, 2000; Rudmik & Soler, 2015). In a recent study, the antibacterial effect of topical budesonide (Pulmicort), a commercial nasal steroid, and its excipients, was evaluated against planktonic and biofilm forms of MRSA.…”

Tackling superbugs in their slime castles: innovative approaches against antimicrobial-resistant biofilm infections

“…An example is the use of excipients that are part of pharmaceutical formulations. While being part of commercial products, excipients such as ethylenediaminetetraacetic acid can show antibacterial effects and added as an adjuvant to the efficacy of therapies with and without antibiotic administration 23 .…”