Necrotizing otitis externa: diagnosis, treatment, and outcome in a case series

Diagn Microbiol Infect Dis. 2017 Jan;87(1):74-78. doi: 10.1016/j.diagmicrobio.2016.10.017. Epub 2016 Oct 18.

Abstract

We reviewed 25 cases of patients diagnosed with necrotizing otitis externa in our tertiary university-affiliated medical center between 2009 and 2015. Mean overall hospitalization duration was 14.52days, 95% of the patients showed specific seasonal incidence. Mean duration of symptoms prior to hospitalization was 6weeks and the duration correlated with outcome. Only 8% of the patients presented with cranial neuropathies; however, this presentation correlated with adverse outcome. Pseudomonas aeruginosa was the main causative organism (50%), with a 30% multidrug-resistance rate. A high rate (35%) of fungal pathogens was noted. Seventeen patients (68%) were eventually operated; however, only 5 patients needed extensive surgery under general anesthesia. Computed tomography (CT) evidence of adjacent structures' involvement correlated with adverse outcome. Eighty percent of our patients improved clinically. The overall death rate was 12% and the disease-related mortality rate was 8%. Our findings state the importance of limited surgical intervention and microbiologic cultures in disease treatment. This is particularly important in patients with cranial neuropathies and CT finding of adjacent structural involvement that correlate with adverse prognosis. A rising pseudomonal antibiotic resistance and fungal infections may challenge antibiotic treatment in the future.

Keywords: Antibiotic resistance; Fungal infection; Necrotizing; Otitis externa; Otogenic; Skull-base osteomyelitis.

MeSH terms

  • Academic Medical Centers
  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Infective Agents / therapeutic use
  • Bacteria / classification
  • Bacteria / drug effects
  • Bacteria / isolation & purification
  • Debridement
  • Female
  • Fungi / classification
  • Fungi / drug effects
  • Fungi / isolation & purification
  • Humans
  • Incidence
  • Length of Stay
  • Male
  • Microbial Sensitivity Tests
  • Middle Aged
  • Necrosis / diagnosis*
  • Necrosis / epidemiology
  • Necrosis / therapy*
  • Otitis Externa / diagnosis*
  • Otitis Externa / epidemiology
  • Otitis Externa / therapy*
  • Seasons
  • Survival Analysis
  • Tertiary Care Centers
  • Treatment Outcome

Substances

  • Anti-Infective Agents