Patient Studies

Therapeutic efficacy of topical glycerol in atrophic rhinitis: A case series analysis

Lien Deschuytere, Shavina Frank, Darlene Lubbe

Received: 06 June 2024; Accepted: 02 Dec. 2024; Published: 24 Jan. 2025

Copyright: © 2025. The Author(s). Licensee: AOSIS.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Introduction: Managing atrophic rhinitis (AR) poses ongoing challenges, with no clear consensus on the optimal treatment approach. Recent exploration into the utilisation of biomaterials in rhinology presents a promising avenue for research. Among these biomaterials, glycerol stands out for its multifaceted benefits in postoperative sinonasal care. Its properties include improved lubrication, preservation of mucosal moisture and facilitation of platelet adhesion and aggregation, thus promoting efficient wound healing processes. The purpose of this case series was to assess the impact of glycerol applied topically to the nasal mucosal in individuals diagnosed with secondary AR.

Patients’ presentation: We identified three patients with secondary AR.

Management and outcome: Topical glycerol was administered daily, with twice daily saline irrigations. Follow-up for these patients was conducted in our outpatient department. Subjective and objective endoscopic measurements of nasal features improved markedly at 6 weeks follow-up.

Conclusion: The application of topical glycerol has demonstrated both subjective and objective efficacy in alleviating sinonasal symptoms associated with AR. It effectively prevents excessive mucosal loss, reduces crusting and enhances ventilation in affected patients.

Contribution: Managing AR has historically presented challenges. However, the introduction of topical glycerol application offers a novel, cost-effective and widely accessible option for addressing mucosal changes in the sinonasal region.

Keywords: atrophic rhinitis; management; sinonasal care; glycerol; glycerin; Total Nasal Symptom Score; Sino-Nasal Outcome Test 22; Lund-Kennedy Score.

Introduction

Atrophic rhinitis (AR) is a debilitating disease characterised by progressive atrophy of the nasal mucosa and turbinate bones, stemming from various aetiologies. It can be classified as primary or, where it is a consequence of another condition or event, secondary. The exact aetiology of primary AR is unknown, but many factors, such as nutritional deficiencies, autonomic dysfunction and biofilm formation, are implicated. Secondary AR, however, is known to develop as a consequence of extensive nasal surgery, granulomatous diseases, immune disorders, radiation therapy and others.¹ The pathology results in crusting, fetor and enlargement of the nasal space with paradoxical nasal congestion.^1,2 The main goal of treatment is to improve the functionality of the mucosa by restoring hydration and minimising crusting.¹

A wide variety of treatment modalities have been described in the literature; however, the mainstay of treatment is conservative. A 2012 Cochrane review¹ concluded that there is no evidence from randomised controlled trials concerning the long-term benefits or risks of different treatment modalities for AR.

Basic medical treatment emphasises moistening measures with the removal of crusts and scabs through nasal irrigation or instrumental cleaning by an Ear, Nose and Throat (ENT) specialist. Effective irrigation solutions include buffered or unbuffered saline, 25% glucose in glycerin and antibiotic solutions, while hypotonic solutions such as tap water are discouraged. Bacterial superinfections, including ozena, are managed with antibiotics such as rifampicin or ciprofloxacin. Besides this, nasal drops (e.g. glucose glycerin), systemic antibiotics, submucosal injections and supplements to improve mucosal hydration, reduce infection and enhance regeneration can be implemented. Surgical interventions aim to reduce nasal cavity size or temporarily occlude it to resolve crusting and social stigma while balancing nasal breathing and olfactory function. Submucosal implants using patient-derived materials such as cartilage or acellular dermis (e.g. AlloDerm) are preferred over foreign materials, showing promising results in reducing symptoms. More recently, the use of materials such as autologous fat, platelet-rich plasma and novel stents (e.g. hydroxyapatite or plastipore) for augmentation has shown variable success, improving mucosal regeneration and reducing crusting.^1,2,3

The use of biomaterials in rhinology is another relatively new area of research. Biomaterials are currently used to replace or repair damaged tissue. Some have shown promise in preventing synechiae after Endoscopic Sinus Surgery (ESS).⁴ Chitosan-based gel, a biological inert amino polysaccharide absorbable material derived from crustacean shells, has gained popularity among biomaterials. Its many properties include haemostasis, prevention of adhesions and antibiofilm formation, which can accelerate wound healing.^5,6,7,8,9

Glycerol, which has similar hydrophilic properties as chitosan-based gel, is a polymer humectant and emollient and is a well-established biomaterial used throughout the biomedical field.¹⁰ Glycerol offers several advantageous properties for postoperative sinonasal care. Its hygroscopic characteristics contribute to enhanced lubrication and the preservation of mucosal moisture, thus reducing transepithelial water loss (TEWL). Moreover, glycerol facilitates platelet adhesion and aggregation, promoting the process of wound healing. Recent studies have shown that glycerol shows promise as a bacteriostatic agent and may play an important role in the inhibition of Staphylococcus aureus colonisation and biofilm formation, reducing infection in these patients.^{10,11,12,13,14,15,16,17}

The objective of this case series is to describe the effect of topical glycerol on the sinonasal mucosa in patients with AR and to review the improvement in nasal crusting and obstruction and prevention of excessive mucosal loss.

Ethical considerations

Ethical clearance to conduct this study was obtained from the University of Cape Town Faculty of Health Sciences Human Research Ethics Committee (No. HREC REF 715/2023).

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. Written informed consent was obtained from all individual participants involved in the study.

Patient presentation

All patients were included between 01 December 2022 and 31 March 2023 and followed up at Groote Schuur Hospital or Mediclinic Cape Town, South Africa.

Case 1

A 62-year-old male patient with epidermolysis bullosa acquisita (EBA) was followed up in the Otolaryngology department complaining of nasal obstruction, crusting and recurrent epistaxis. His Total Nasal Symptom Score (TNSS) and Sino-Nasal Outcome Test 22 (SNOT-22) were 6 out of 9 and 46 out of 110, respectively. Nasal endoscopy showed significant crusting and bloody, friable sinonasal mucosa. Lund-Kennedy Score (LKS) was 7 out of 20.

Case 2

A 56-year-old male patient was followed up after endoscopic resection and adjuvant chemoradiation for an olfactory neuroblastoma. In 2019, the patient underwent an initial endoscopic resection of an olfactory neuroblastoma involving the right sinonasal cavity, cribriform plate and dura with clear margins. Following a recurrence, a second endoscopic resection was performed in the left sinonasal region in 2021. Postoperatively, the patient was treated with chemoradiation. During follow-up, he complained of nasal crusting bilaterally. His TNSS and SNOT-22 were 6 out of 9 and 63 out of 110, respectively. Nasal endoscopy showed significant crusting and bleeding, LKS amounted to 8 out of 20.

Case 3

A 37-year-old female patient was followed up in our outpatient department for EBA with predominant nasal, glottic and tracheal complaints. She primarily reported symptoms of hypernasality and nasal obstruction. Her TNSS and SNOT-22 were 5 out of 9 and 68 out of 110, respectively. Nasal endoscopy showed scar bands and nasopharyngeal stenosis, with an LKS of 14 out of 20.

Management and outcome

Cases 1 and 3 were taken to theatre for endoscopic endonasal debridement with removal of crusts, the division of adhesions and to address any relevant stenosis. In all patients, topical glycerol application was initiated and continued on a once-daily basis for 2 weeks and routine twice-daily nasal saline douches were continued as per their pre-treatment regime. Subjective as well as objective endoscopic measurements of nasal features improved markedly at 6 weeks of follow-up (see Figure 1). The results of the TNSS, SNOT-22 and LKS are summarised in Table 1. They all show a substantial improvement, with a noteworthy reduction in nasal obstruction.

FIGURE 1: Pre- and post-treatment pictures. (a) Case 1, (b) Case 2 and (c) Case 3.

Discussion

Atrophic rhinitis is a chronic, degenerative condition characterised by inflammation and atrophy of the nasal and paranasal mucosa and structures. The classic constellation of symptoms of AR includes thick and adherent crusting, foul odour (or fetor) and nasal obstruction. The hardened crusts that develop have classically been referred to as rhinitis atrophicans cum foetore or ozena.¹⁸

Atrophic rhinitis is classified into primary and secondary types. Primary AR presents with spontaneous onset and progresses slowly with time. In contrast, the secondary form is associated with underlying causes that may include nasal surgery, radiation therapy or granulomatous diseases.³

In this case series, we describe three cases of secondary AR. Two individuals were diagnosed with EBA. This is a rare chronic autoimmune bullous disease characterised by recurrent subepidermal blistering, which in turn may gradually lead to scarring of skin and mucous membranes. To date, there exists no established standard treatment protocol for EBA and current classic treatment schemes are often ineffective and cause side effects.¹⁹

The third patient underwent endoscopic resection and subsequent chemoradiation for an olfactory neuroblastoma.

Thus far, management of the sinonasal mucosal changes linked with AR has proven to be challenging. Treatment is usually conservative, focusing on reducing crust formation and enhancing nasal hydration. Nasal douches are frequently suggested, and a plethora of nasal drops have been proposed, albeit with varying levels of effectiveness. There persists an ongoing contentious debate regarding potential surgical interventions, implants and submucosal injections, perpetuating divided opinions.³

While the use of biomaterials in rhinology has acquired remarkable attention by surgeons, much is to be learnt regarding their promising effect on wound healing and prevention of synechiae following ESS.⁵ Chitosan-based gel has garnered attention in the realm of biomaterials because of its diverse array of properties. These include its ability to induce haemostasis by promoting platelet adhesion and aggregation, which is hypothesised to occur independently of the classical coagulation cascade.⁵ Additionally, chitosan demonstrates efficacy in preventing adhesions and inhibiting biofilm formation while also facilitating accelerated wound healing processes.^6,7,8,9 A commonly utilised chitosan-based biomaterial, Chitogel (Medtronic), which contains chitosan, dextran and glycerol, is shown to exhibit the haemostatic, fibrin inhibition and moisturisation properties, respectively.²⁰

Glycerol, a humectant and an emollient, has been used in the biomedical field for many years with a wide range of applications: cryopreservation of tissues, in dermatological and wound dressing agent, and as a key component of medical lubricants.¹¹ Among its many properties, the hygroscopic nature of glycerol exhibits lubricating and hydrating function, adhering and clearing well from mucosa reducing TEWL to retain moisture.¹² Glycerol-containing products have shown to enhance platelet adhesion and aggregation to promote wound healing.^5,13 The role of glycerol as an antibacterial agent in sinus mucosa is not well known. However, it exhibits bacteriostatic mechanisms of a common sinonasal commensal, Corynebacterium accolens. Its presence is linked to the inhibition of S. aureus colonisation and its related biofilms through glycerol metabolic compounds.^14,15,16,17 A major advantage of glycerol is its low cost and widespread availability.

In this case series, three patients with AR were treated with the topical application of pure glycerol. The treatment demonstrated a positive impact on the symptoms of AR, reinforcing its known efficacy in other medical applications. Glycerol was found to prevent excessive mucosal loss, reduce crusting and improve nasal ventilation in affected patients. These findings highlight glycerol as a valuable adjunct in the comprehensive management of AR in South Africa.

Conclusion

Although the cohort size remains modest and results can therefore not be generalised, the preliminary findings in this case series highlight the considerable potential of glycerol as an adjunctive therapeutic option for AR. It prevents excessive mucosal loss, minimises crusting and has a beneficial effect on nasal ventilation in patients afflicted by AR.

Further prospective studies are warranted to validate these findings and ascertain the optimal duration and route of administration for glycerol.

Acknowledgements

The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article.

D.L. conceived of the presented idea. D.L., and S.F. reviewed the patients clinically. S.F. performed the analysis of the results, L.D. interpreted the data. All authors discussed the results and contributed to the final article.

This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.

The authors confirm that the data supporting the findings of this study are available within the article.

The views and opinions expressed in this article are those of the authors and are the product of professional research. It does not necessarily reflect the official policy or position of any affiliated institution, funder, agency or that of the publisher. The authors are responsible for this article’s results, findings and content.

References