Keywords gout - temporomandibular joint - joint diseases
Introduction
Gout is an illness characterized by the deposition of monosodium urate crystals in
the joints or in soft tissues,[1 ]
[2 ] leading to acute inflammation with associated pain, impaired movement of the affected
joint, and hyperuricemia.[3 ] The small joints of the limbs and the elbows and knees are the usually affected
sites.[3 ]
[4 ]
[5 ] The temporomandibular joint (TMJ) is rarely involved.[3 ]
[4 ]
[5 ] There are currently few reports in the English medical literature relating gout
and TMJ. The article aims to report a presentation of gout in the TMJ and discuss
the pertinence of the role of physical and complementary exams addressed to the case.
Case Report
A 66-year-old white man presented for consultation at the Department of Oral and Maxillofacial
Surgery, Centro Médico Rio Branco, in May 2011. He reported occasional pain in the
left temporal muscle region for 1 year. In this period, the patient used nonsteroidal
anti-inflammatory drugs (NSAIDs) with improvement of the symptoms. The longest period
of NSAID use lasted a month. At the consultation, the patient complained about a volumetric
augmentation in the aforementioned region. There was no history of diseases, although
the patient reported hyperuricemia in previous hematologic exams.
Extraoral physical examination showed a volumetric augmentation in the left temporal
region, matching the patient report ([Fig. 1 ]). Massage of the left parotid gland showed no purulent discharge. The patient denied
previous trauma in the examined regions.
Fig. 1 Increased volume in the left temporal region on physical examination.
Due to the suspicion of a gout manifestation, complementary exams were requested.
The blood tests showed high glucose (117 mg/dL—reference values: 60 to 99 mg/dL),
high creatinine (1.6 mg/dL—reference values: 0.4 to 1.3 mg/dL), and high uric acid
(8.1 mg/dL—reference value: 3.4 to 7.0 mg/dL). Ultrasonography indicated a normal
parotid gland and a left hypoechoic palpable area, with well-defined contours measuring
3.7 × 1.0 cm ([Fig. 2 ]). According to the radiologists report, “The examined region presented alterations
that may correspond to accumulation of subcutaneous tissue.” Orthopantographic radiography
revealed a change in the morphology of the left mandible condyle ([Fig. 3 ]).
Fig. 2 Ultrasonography revealing a well-defined hypoechoic area, measuring ∼3.7 × 1.0 cm.
Fig. 3 Orthopantographic radiography revealing a morphologic change of the left mandibular
condyle.
The sum of anamnesis, physical examination, and laboratory tests undoubtedly indicated
a gout manifestation in the TMJ. The patient was informed of his condition and referred
to a rheumatologic consultation in July 2011. The patient skipped the follow-up consultations.
Discussion
Gouty arthritis is a metabolic illness that most often affects middle-aged men and
presents with pain, swelling, local sensitivity, and, in the majority of cases, hyperuricemia.[2 ]
[3 ] Monosodium urate deposits are located mainly in some small joints of the upper and
lower limbs.[3 ]
[4 ] Pain and limitations of mandibular functions may suggest some diagnoses such as
arthritis, inflammatory diseases, or tumors of the TMJ.[5 ]
[6 ] The manifestation of gout should be also included in the diagnoses despite of its
rare occurrence.[5 ]
[6 ]
Bhattacharyya et al presented, after a clinical trial, some features of TMJ gout such
as limited mouth opening with mandibular deviation and the occurrence of pain, swelling,
joint sounds, and impaired movement.[5 ] Suba et al also reported decreased mouth opening as a symptom of gout.[3 ] Cacioppi et al presented a unique case of malocclusion of the mouth associated with
extensive involvement of gout in the whole body as well as symptoms indicating rheumatoid
arthritis.[1 ] The case presented here showed coincidental features noted by other authors. The
patient was a 66-year-old man complaining of pain and limitations and swelling in
the left TMJ region.
Complementary exams can be very helpful when the suspected disease is gout. However,
a meticulous anamnesis and a thorough physical examination are paramount for the correct
diagnose.[1 ]
[5 ]
[6 ] Because our patient reported a previous blood exam showing hyperuricemia, the clinical
investigation was directed to a possible gout manifestation.
According to Suba et al,[3 ] the elevated concentrations of urate in the serum and in the urine or the knowledge
of previous episodes of gout can help differentiate the illness from other joint diseases.
Because one-third of patients present with hyperuricemia, radiography, computed tomography,
and biopsy of the lesions could help confirm suspected cases of gout. Nevertheless,
Kleinman and Ewbank asserted that the high levels of uric acid in the bloodstream
at the time of the consultation, associated with the remission of the symptoms after
drug treatment (NSAIDs, glucocorticoids, and colchicine), suggest gout.[6 ] According to them, it also excludes the need for a biopsy. These authors presented
three cases of gout diagnosed after careful clinical investigation. The actual case
report corroborates Bhattacharyya et al[5 ] and Kleinman and Ewbank,[6 ] as it was conducted after a diligent clinical appraisal. We could also study some
other exam findings. The ultrasonography presented a well-defined swelling beneath
the skin and a left condyle distortion, suggesting gout manifestation in the TMJ.
In the present case report, the sum of anamnesis and the physical and complementary
exams pointed to the diagnosis of gout, revealing the sovereign value of the clinical
approach.
Conclusion
Gout in the TMJ, despite being rare, should be included as a differential diagnosis
for joint disorders. A previous history of gout with improvement after the use of
NSAIDs may favor the diagnosis of gout, leading to the right treatment. The complementary
exams can be helpful pinpoint TMJ cases of gout and discard some other diseases that
normally affect the region.
