Bilateral septic arthritis of the temporo mandibular joint: case report

Septic arthritis of the temporo-mandibular joint (TMJ) is a rare disease that has been reported infrequently. To the best of the authors' knowledge, only one case of bilateral TMJ septic arthritis has been reported. The contamination may result from direct extension of adjacent infection (dental or ENT), from hematogenous spread of blood-borne organisms or from direct inoculation. The most common presenting are trismus and pain, although swelling, tenderness and erythema have also been described. In addition, patients may develop fever, regional lymphadenopathy and malocclusion. Through a successively bilateral case of TMJ arthritis, without obvious portal of entry of the bacteria, we will analyze characteristics and treatment of this disease.


Introduction
Septic arthritis of the temporomandibular joint (TMJ) has rarely been reported [1]. This condition is mainly arises from direct extension of head and neck infection or occasionally by hematogenous dissemination [2]. The most common pathogen isolated in septic arthritis of TMJ is S aureus followed by Neisseria and streptococcus [2,3]. Clinical manifestations include pain, swelling in the TMJ, trismus and malocclusion. Symptoms are often not as typical as they were previously, owing to the widespread use of antibiotics [1,2]. Timely diagnosis with early treatment is the most significant predictor of a successful outcome [3]. Through a successively bilateral case of arthritis, without obvious portal of entry of the bacteria, we review literature and we will analyze characteristics and treatment of this topic.

Discussion
Septic arthritis of the temporo-mandibular joint (TMJ) has been reported infrequently [1]. To the best of the authors' knowledge, only one case of bilateral TMJ septic arthritis has been reported [2]. This small number of reported cases may be the result of misdiagnosis or underreporting. Several authors have suggested that a significant percentage of cases of mandibular complications such as ankylosis and abnormal growth, may have resulted from failure to diagnose TMJ septic arthritis [3,4]. Susceptible patients are those with diabetes, systemic lupus erythematous, rheumatic arthritis, or immunosuppressive diseases [5]. The contamination may result from [6,7]: extension of adjacent infection in soft tissues or bone (dental or ENT); hematogenous spread of bacteria from distant infection or intravenous drug use; direct inoculation by penetration of the joint space traumatically or intra-operatively.
Recent studies have shown that micro-organisms are most commonly seeded hematogenously, but the original infectious sites were often occult. Staphylococcus aureus is the most commonly isolated organism from patients with septic arthritis of TMJ, although Streptococcus species, Neisseria and Haemophilus influenza have also been reported in the literature [6,8,9]. The most common presenting are trismus and pain, although swelling, tenderness and erythema have also been described as did our patient. In addition, patients may develop fever, regional lymphadenopathy and malocclusion [1,2,9]. In many instances, patients may not have a classic presentation and symptoms may be confused with other diseases, such as cellulitis, rheumatic disease, Page number not for citation purposes 3 condylar hypertrophy or synovial chondromatosis [1,3]. Imaging studies are helpful for diagnosis [7]. Joint space widening is generally demonstrated in panoramic in the acute stage [2].
CT scan is advantageous in chronic stage because it can show the bony changes earlier in addition of peri-articular soft tissues and identify infectious osteoarthritis [8,9]. Erosive changes were seen on the CT of our patient when she had been symptomatic only 2 weeks. The magnetic resonance imaging is recommended because its sensitivity for the early detection of increased joint effusion [2,5]. Laboratory examinations are also helpful for the diagnosis if inflammatory signs are found but sometimes they can be normal because of the use of antibiotics [2]. Although the diagnosis of septic arthritis of the TMJ is ideally made by the identification of organisms in the aspirated fluid [2,3,10]. Therefore other evidence, such as clinical presentation, radiographic appearance, laboratory values, response to antibiotics and exclusion of other disease may provide critical informations. Treatment should be initiated promptly to avoid irreversible complications such as abscess or necrosis of the condyle [8]. The treatment of osteoarthritis consists primarily of rest therapy (restricting jaw movements), medical treatment (analgesics, antinflammatories), splint therapy or minimally invasive therapy. Antibiotic treatment must be continued for as long as possible, a total of 30 days therapy has been recommended [2,3,8]. Arthroscopy, being a minimally invasive procedure, should be preferred to open surgery when possible as the initial treatment and not only after needle aspiration failure [3,10]. Surgical drainage has been suggested if abscess formation is present, if bony changes are radiographically evident or when antimicrobial therapy alone has failed to produce resolution of infection [3,8]. Our patient was operated in front of the presence of abscess and peri-articular osteolysis condyle. The bacteriological examination was negative because of use of antibiotics. Infected joints usually become sterile 48 to 72 h after drainage [2]. Physical therapy is necessary to improve mandibular range of motion and deviation of opening movement. Moreover early rehabilitation exercises are important to ovoid complications such as fibrosis and ankylosis [2,3].

Conclusion
Septic arthritis of the TMJ is a rarely reported entity whose occurrence might be more common if clinicians were aware of its possibility. Early diagnosis and treatment are essential to avoid possible sequelae and complications such as dissemination of infection, joint dysfunction, growth disturbances, fibrosis, and ankylosis.

Competing interests
The authors declare no competing interests.

Authors' contributions
All authors have read and agreed to the final version of this manuscript and have equally contributed to its content and to the management of the case. Figure 1: Mild preauricular swelling on the right side