Surgical Treatment of Tonsillar Abscess

The diagnosis and treatment of tonsillar abscess are very physician-dependent, as sufficient prospective medical literature is lacking to choose the most efficient regimen. The proposed study aims to assess the therapeutic efficacy of tonsillectomy compared to drainage under local anesthesia. This is a prospective, randomized clinical trial in adults in a tertiary care center in Geneva (Switzerland).

Introduction:

Tonsillar abscess is the most common complication of acute bacterial angina. The abscess is located in the majority of cases in the capsular space and occasionally within the tonsil itself. The ethiopathogenesis is polymicrobial, composed mainly of Streptococcus Pyogenes (aerobic) and Fusobacterium Necrophorum (anaerobe). This condition mainly affects young adults, smokers and significantly impacts quality of life. Symptoms are noisy, characterized by severe odynodysphagia, often limited mouth opening (trismus), and occasionally dyspnea, fever, and decreased general condition. Its complications include upper airway obstruction, spread of infection into the deep tissues of the neck and mediastinum, septic venous thrombosis, and arterial hemorrhage from contact necrosis. The descriptions of the management of this pathology are centuries old, but even today there is a need to drain the pus. We estimate that around 200 patients per year present to our University Hospital in Geneva (Switzerland) with suspected tonsillar abscess.

Diagnosis:

The medical literature describes several diagnostic methods without clear consensus on the most effective. The doctor's clinical suspicion varies according to the examiner's experience, although certain criteria are recognized as good predictors of the presence of an abscess (trismus, edema, uvula deviation, "hot potato voice", reflex otalgia), but with limited sensitivity and specificity. When clinically suspected, confirmation of the presence of pus can be determined by direct puncture or drainage, allowing immediate diagnosis, but with a high proportion of false negatives and requiring a painful invasive procedure. Ultrasound (US) and Computed Tomography (CT) provide a painless diagnosis, but US requires a specific oral probe and may be unfeasible in case of trismus, and its interpretation is very examiner-dependent. CT remains an irradiating, costly and time-consuming exam, but it is sensitive and can formally exclude any associated complication (venous thrombosis, retro- or parapharyngeal extension, contralateral involvement). The gold-standard for the diagnosis of a tonsillar abscess is the direct visualization of pus during drainage.

Treatment:

Regarding the treatment, here too the evidence-based literature is not clear about the most effective (except in children, in whom local anesthesia intervention is most of the time impractical). It usually consists of a combination of medical and surgical therapy. Medical therapy generally includes - in addition to hydration and pain-killers - intravenous antibiotics and requires approximately 3 days of hospitalization. There are several described technics for the surgical drainage. Repeated needle punctures, incisional drainage under local anesthesia, and tonsillectomy under general anesthesia. The latter two are favored because they are more effective on immediate pain. To our knowledge, only two prospective randomized studies (partially for one) of 51 and 53 patients have studied the efficacy of these two interventions and their conclusions only relate to the absence of difference in the length of hospital stay.

The retrospective data show good efficacy of both modalities (incision drainage under local anesthesia vs tonsillectomy under general anesthesia) and the choice of their execution is strongly center- and physician-dependent. Incision drainage avoids general anesthesia but is extremely unpleasant, requiring repeated rinsing which is painful for the patient and time-consuming for the medical team. This modality is grafted with a failure rate of around 20% in the literature as well as in our own experience, requiring further tonsillectomy under general anesthesia. Furthermore, the recurrence rate is estimated at 9-22%. Conversely, the first-line tonsillectomy requires a general anesthesia but immediately relieves some of the pain and the trismus, allows an almost certain resolution of the infection, prevents any recurrence, seems economically more advantageous and does not require the collaboration of the patient during the procedure.

As the medical literature does not offer clear guidelines based on prospective trials, the proposed study aims to prospectively evaluate the therapeutic efficacy of the tonsillectomy compared to the drainage under local anesthesia.

This is a prospective, randomized clinical trial by adults in a tertiary care center in Geneva (Switzerland).

Eligibility Criteria:
Inclusion Criteria:

* Patients ≥18 years of age with clinical suspicion of unilateral tonsillar abscess without signs of "extra-capsular" complication.
* Obtaining informed consent.

Exclusion Criteria:

* Contraindications to injected CT or drainage in local anesthesia (allergy to iodinated contrast product, allergy to local anesthetics, phobia of needles, major trismus).
* Parapharyngeal or retropharyngeal abscess, or associated venous thrombosis found on CT.
* Imminent threat to the upper respiratory tract (glottic edema, acute dyspnea).
* Inability to understand the different procedures (dementia, impossible communication, substance abuse).
* Anamnestic pregnancy.
* Antiaggregant or anticoagulant treatment.
* Treatment of corticosteroids during the management of emergencies and in hospital.