Fluorescence diagnosis of upper respiratory tract infections

Abstract

The pharyngitis and laryngitis are respiratory tract infections highly common. Pharyngitis can be accompanied by fever, especially if caused by a systemic infection. Laryngitis is an inflammation of your voice box (larynx) from irritation or infection. The conventional treatment is the antibiotics administration, which may be responsible by an increase of identification of bacterial strains resistant to drug. This fact associated to high incidence of these infections become important to develop new technologies for diagnosis. This study aims to evaluate the use of widefield fluorescence imaging for the characterization of oropharynx infections, in order to diagnose the bacteria colonization. The imaging system for wide field fluorescence visualization is Evince® (MMOptics, São Carlos, SP, Brazil) coupled to an Apple iPhone® cell phone device. The system consists of Light Emitting Diodes (LEDs) operating in the violet blue region centered at green-red spectrum 450 nm and optical filters that allow viewing of fluorescence. A tongue depressor was adapted to Evince® for mouth opening. The same images were captured with white light and fluorescence with an optical system. The red fluorescence may be a bacterial marker for physiological monitoring of oropharynx infection processes. The bacterial biofilm on tissue were assigned to the presence of protoporphyrin IX. This work indicates that the autofluorescence of the tissue may be used as a non-invasive technique to aid in the oropharynx infection diagnostic.