Scope and target group

The purpose of the guideline is to provide the best possible care to patients with skull base osteomyelitis, by informing on optimal diagnostic and treatment decisions and reducing unwarranted variation in the delivery of care. It is intended for all healthcare providers in the secondary and tertiary care setting who are involved in the care of patients with osteomyelitis of the skull base – necrotizing otitis externa.

However, early recognition of the diagnosis in the first line is essential. In the Netherlands, there is a high-quality guideline for common otitis externa, which also includes advice for general practitioners regarding referral to an ENT specialist.

The guideline development group is aware of the low incidence of the disease. By writing the guideline in English the guideline development group aims to make it accessible to a wide audience. Although (local) initiatives are taken aimed at improving various aspects of care related to this condition, this guideline provides a broad, multidisciplinary framework for clinicians treating patients with this condition globally.

Apart from the low incidence of this condition the working group is faced with several challenges:

• There are few available studies, often written in various languages.
• There is no clear consensus about the nomenclature as well as the definition of the disease.
• There is considerable variation in diagnostics, as well as in treatment and treatment monitoring due to major differences in healthcare resources globally and differences in clinical practices.
• When determining the optimal treatment (duration) for such an infection, there is a lack of well-conducted comparative research that takes into account various parameters:
• Type and virulence of pathogen
• Extent of the infection at the time of diagnosis
• Individual patient-dependent parameters that may influence the success of the treatment
• Significance of residual abnormalities in imaging during the course of treatment.

Finally, the treatment of infectious diseases is also subject to local differences due to varying resistance patterns of the causative pathogens. Where relevant, the guideline will indicate if a specific situation applies to the Dutch healthcare system.

For patients

This guideline is intended for patients with necrotizing otitis externa. It covers the following aspects: recognition of the diagnosis, diagnostics, treatment, and follow-up.

Voor patiënten

Deze richtlijn is bedoeld voor patiënten met osteomyelitis schedelbasis – maligne otitis externa. De richtlijn is geschreven in het Engels. In deze richtlijn komen de volgende onderdelen aan bod: de herkenning van de diagnose, diagnostiek, behandeling en follow-up.

Development of the guideline

The initiative for this guideline comes from the Dutch Society for Otorhinolaryngology and Head and Neck Surgery (NVKNO). In 2022, a multidisciplinary guideline development group was formed with representatives from ENT specialists, radiologists, nucleair medicine physicst, infectious disease specialists and medical microbiologists. Hospital pharmacists and a patient representative reviewed the guideline before the commentary phase.

Application

A flowchart was developed to guide clinicians through the appropriate steps of diagnosing and treating the disease.

Status of the guideline

The guideline on osteomyelitis of the skull base – malignant otitis externa is included in the Otology cluster and will be maintained modularly within this cluster. More information about working in clusters and modular maintenance can be found here (in Dutch).