Factors Associated With Infectious Laryngitis: A Retrospective Review of 15 Cases

Abstract

Objectives: To identify the culturable microbes associated with infectious laryngitis and outline effective treatment strategies.

Methods: This is a retrospective chart review of adult patients with persistent dysphonia plus evidence of laryngeal inflammation who underwent biopsy for culture at a tertiary care medical center. Demographic factors, symptoms as reported on validated patient assessment tools, past medical history, social history, culture results, and treatment duration and response were reviewed.

Results: Fifteen patients with infectious laryngitis were included in this study. Culture results demonstrated Methicillin-sensitive Staphylococcus aureus (MSSA), Methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Serratia marcescens, and "normal respiratory flora." In most patients, multiple courses of prolonged antibiotics were needed to treat MSSA or MRSA. Infections associated with other microbes resolved with a single course of antibiotics.

Conclusions: In this population, infectious laryngitis is defined as colonization with bacteria not found in the previously characterized laryngeal microbiome of benign vocal fold lesions. In suspected cases of infectious laryngitis, culture is recommended, by biopsy if needed. For MSSA- and MRSA-associated laryngitis, an extended course of antibiotics may be necessary for symptom improvement and resolution of laryngeal inflammation. However, the optimal treatment regimen has yet to be defined and will require larger, prospective studies.

Keywords: Staphylococcus aureus; bacteria; chronic laryngitis; infectious laryngitis; inflammation; laryngitis.

Figure 1

Laryngoscopy image of chronic laryngitis. Laryngoscopy findings seen in chronic bacterial laryngitis include edema, erythema, crusting, and exudate. The presence of exudate is most commonly associated with bacterial etiology.

Figure 2

Bacterial species isolated from chronic laryngitis cultures. Culture results demonstrated a predominance of Methicillin-sensitive Staphylococcus aureus as the causative organism for chronic laryngitis (12/15). Serratia marcescens was isolated from 2 cultures while Pseudomonas aeruginosa and Methicillin-resistant Staphylococcus aureus were each isolated from 1 out of 15 cultures. One culture demonstrated only “normal respiratory flora” despite the larynx having the characteristic appearance of chronic bacterial laryngitis.

Figure 3

Representative laryngoscopy images of chronic laryngitis pre- and posttreatment. Examples of pathologic findings seen with chronic bacterial laryngitis including edema, crusting, and exudate from 4 separate patients (Patient Nos. 1–4) are demonstrated. Panels on the left are pretreatment, and panels on the right are the corresponding posttreatment photographs.