Sinonasal Microbiome Transplant as a Therapy for Chronic Rhinosinusitis Without Nasal Polyps (CRSsNP)

Over the last few years the theory of a damaged microbiome as a cause or promoting factor behind chronic rhinosinusitis has gained increasing interest from the scientific community.

A number of studies aimed at investigating the microbiota of the nose and paranasal sinuses in health and disease has been published with very varying outcomes. Furthermore, other studies have been aimed at probiotic treatment of sinonasal disease either locally or through immunologic manipulation via the gastrointestinal microbiota.

A problem common to all these studies is that studies examining the normal nasal microbiota have identified a great amount of different bacterial species. It is as of today not known which individual species or combinations of species that promotes health.

The probiotic assemblages examined in previous studies have consisted of one or a combination of a few bacterial species.

Probiotic restitution therapy has been proven very effective for intestinal clostridium difficile infections. The restitution therapy has then consisted of transplantation of a complete microbiome from a healthy donor in the form of a faecal transplant.

In this study the investigators aim at recruiting patients suffering from chronic rhinosinusitis without polyps (CRSsNP) and healthy participants without any history sinonasal disease. The patients and the healthy participants will be examined for infectious diseases in a manner similar to other medical transplant procedures to minimize the risk for the recipients. The patients will then be treated with antibiotics to reduce the bacterial load of the nose and the paranasal sinuses. After the patient has finished the antibiotic treatment a microbiome transplant will be harvested from the healthy participant as a nasal lavage. The raw lavage fluid will then be used to transplant the microbiome to the patient. The procedure will be repeated for five consecutive days.

The outcome measures analysed will focus on subjective sinonasal health and symptoms of the patients but also include nasal inflammatory and microbiological indices.

Inclusion criteria

(patient)

• 2 nasal symptoms: 1 of which must be nasal obstruction or discoloured discharge.
• Sinusitis verified by endoscopy or CT-scan.
• Duration > 12 weeks.
• Previous surgery with patent ostia to the diseased sinuses.
• Signed informed consent to participate in the study.

Inclusion criteria

(donor)

• No history of sinonasal or lower airway disease within the last 2 years other than the common cold.
• Accepted as a donor by the patient.
• Signed informed consent to participate in the study.

Exclusion criteria

(patient)

• Nasal polyposis.
• Antibiotic treatment within the last 4 weeks.
• On-going or recent participation in another clinical trial.
• Any medication that may affect the results in an unpredictable manner.
• Immune deficiency.
• Allergy to amoxicillin or clavulanate potassium and clarithromycin.
• Pregnancy or breastfeeding.

Exclusion criteria

(donor)

• Chronic rhinosinusitis.
• Acute rhinosinusitis within the last two years.
• Nasal polyposis.
• Asthma.
• Antibiotic treatment within the last 4 weeks.
• On-going or recent participation in another clinical trial.
• Clinical findings of sinonasal disease at the inclusion visit.
• Findings in the pre-study pathogen scan that makes the donor unsuitable.
• Pregnancy or breastfeeding.