A Subacute Presentation of Isolated Tuberculous Septic Hip Arthritis

Abstract

Tuberculous septic arthritis is a rare type of septic arthritis that is caused by Mycobacterium tuberculosis. However, it can lead to devastating complications if not diagnosed and treated correctly. We hereby report a 41-year-old female with no medical history who presented with a three-week history of right hip pain and inability to bear weight, found to have moderate to severe tenderness at the right anterior hip and gluteal area and limitation of joint movement. Magnetic resonance imaging (MRI) of the hip showed features of right hip septic arthritis with synovitis and anteromedial and posteromedial small collections. She was diagnosed with tuberculosis (TB) after joint fluid aspiration, and she was started on anti-TB treatment including isoniazid, rifampicin, ethambutol, and pyrazinamide directly after. Considering the case and the subacute presentation that can mimic bacterial septic arthritis, clinicians should always consider TB infection in their differential diagnosis upon assessing a suspected patient with septic arthritis even with a subacute presentation to achieve the correct diagnosis and start appropriate treatment to avoid its harmful complications.

Keywords: anti-tb; hip joint; subacute; tuberculosis (tb); tuberculous septic arthritis.

Figure 1. X-ray (anteroposterior view) of the pelvis with both hip joints showing lytic lesion in the right acetabulum (blue arrow).

Figure 2. MRI of the right hip with contrast: axial view in T2WI (A), coronal view in T2WI (B), T2WI with contrast (C), and T2W1 of the right hip (D). There is effusion with synovial thickening of the right hip showing enhancement after contrast (blue arrow) and diffuse bone marrow edema involving the right acetabulum (yellow arrow). A large focus anterior to the right gluteus maximus muscle medially measuring 3.5 × 2.7 cm shows increased signal intensity on T2 with another focus adjacent to the right acetabular labrum measuring 2.8 × 1.7 cm slightly hyperintense on T2, representing collections (red arrow).

MRI: magnetic resonance imaging, T2WI: T2-weighted image