Biofilm formation in persistent infections and its role in the pathogenesis of equine recurrent uveitis (ERU) - a literature review

Geißler, P. und Wollanke, B. (2021): Biofilm formation in persistent infections and its role in the pathogenesis of equine recurrent uveitis (ERU) - a literature review. In: Pferdeheilkunde, Bd. 37, Nr. 3: S. 225-233

Abstract

The formation of bacterial biofilm has gained increasing medical relevance in recent years. The involvement of biofilm has been demonstrated in a wide variety of chronic infections. Biofilm-associated infections are characterised by a chronic and recurrent course of disease, which is associated with immune-mediated tissue damage. The present literature review provides an overview of bacterial biofilm formation and presents its importance to biofilm-associated infections. The relevant pathophysiological mechanisms that occur in vivo during its formation are described by means of selected biofilm-associated infections. Equine recurrent uveitis (ERU) is a chronic disease of the equine eye caused by Leptospira and maintained by their persistence in the vitreous humour. Current research indicates that leptospiral biofilm might be involved in the pathogenesis of ERU. Biofilm bacteria are protected from the effects of the immune system and can be eliminated by antibiotics with great difficulty if at all. Chronic bacterial infections are, therefore, often associated with the formation of biofilms. The persistence of Leptospira in the vitreous humour triggers recurring bouts of inflammation, which damage the internal eye structures and, if left untreated, lead to blindness in horses. Intraocular biofilm formation might serve as a persistence mechanism since Leptospira can survive in the horse's vitreous humour and are capable of biofilm formation. When comparing ERU with biofilm-associated infections, such as chronic P. aeruginosa infection in cystic fibrosis patients or chronic wound infection, numerous similarities in the pathogenesis, diagnosis and therapy are evident. Recent investigations of vitreous material from affected horses have demonstrated leptospiral biofilm formation in the vitreous humour. The formation of biofilm in the equine vitreous humour might offer an explanation for both the persistence of Leptospira in the eye and the chronic recurrent pattern of the disease. Furthermore, the autoimmune phenomena observed in ERU might be explained by the presence of biofilm in the vitreous humour. Research on the aetiology of ERU and the involvement of intraocular leptospiral biofilm is still in progress. Future studies in the area of biofilm formation may provide further insights in the years to come.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Tiermedizin > Zentrum für Klinische Tiermedizin
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• ISSN: 0177-7726
• Sprache: Englisch