FleQ, a Transcriptional Activator, Is Required for Biofilm Formation In Vitro But Does Not Alter Virulence in a Cholesteatomas Model

The Role of Biofilms in Chronic Otitis Media-Active Squamosal Disease: An Evaluative Study

OBJECTIVES

To study the presence of biofilms in patients of chronic otitis media (COM)-active squamosal disease and to evaluate the microflora and clinical impact of biofilms.

METHODS

A total of 35 patients suffering from COM - active squamosal disease was studied. Cholesteatoma sample was collected at the time of mastoid surgery and the same was used to image for biofilms by scanning electron microscope. The said sample was also analyzed microbiologically.

RESULTS

Biofilms were present in 25 (72%) patients including 6 cases of fungal biofilms (24%). Biofilms were detected irrespective of the micro-organism growth. No statistically significant relationship was observed between biofilms and discharging ear and complications of COM. Though univariate analysis of our data found some correlation between duration of disease, the extent of cholesteatoma and ossicular necrosis but multivariate analysis revealed no such associations, thereby implying a doubtful association between these factors and biofilm.

CONCLUSIONS

Biofilms are an integral part of cholesteatoma ear disease and sometimes harbors fungal isolates.

An Organ System-Based Synopsis of Pseudomonas aeruginosa Virulence

Driven in part by its metabolic versatility, high intrinsic antibiotic resistance, and a large repertoire of virulence factors, Pseudomonas aeruginosa is expertly adapted to thrive in a wide variety of environments, and in the process, making it a notorious opportunistic pathogen. Apart from the extensively studied chronic infection in the lungs of people with cystic fibrosis (CF), P. aeruginosa also causes multiple serious infections encompassing essentially all organs of the human body, among others, lung infection in patients with chronic obstructive pulmonary disease, primary ciliary dyskinesia and ventilator-associated pneumonia; bacteremia and sepsis; soft tissue infection in burns, open wounds and postsurgery patients; urinary tract infection; diabetic foot ulcers; chronic suppurative otitis media and otitis externa; and keratitis associated with extended contact lens use. Although well characterized in the context of CF, pathogenic processes mediated by various P. aeruginosa virulence factors in other organ systems remain poorly understood. In this review, we use an organ system-based approach to provide a synopsis of disease mechanisms exerted by P. aeruginosa virulence determinants that contribute to its success as a versatile pathogen.