Tuberculosis arthritis

Tuberculosis arthritis is an infectious form of arthritis caused by the bacterium Mycobacterium tuberculosis. It is a rare complication of tuberculosis (TB), a disease that primarily affects the lungs but can spread to other parts of the body, including the bones and joints. Tuberculosis arthritis is a form of extrapulmonary tuberculosis, which refers to TB infections outside of the lungs. This condition is also known as tuberculous arthritis or TB arthritis.

Etiology and Pathogenesis

Tuberculosis arthritis results from the hematogenous spread of Mycobacterium tuberculosis from a primary site of infection, usually the lungs, to the joint space. It can also spread through direct extension from adjacent infected bones in cases of osteomyelitis. The knee and hip joints are among the most commonly affected, but TB arthritis can affect any joint in the body.

The pathogenesis involves the deposition of mycobacterial bacilli in the synovial membrane of the joint, leading to an inflammatory response. Over time, this can result in the destruction of cartilage and bone within the joint, causing pain, swelling, and reduced mobility.

Clinical Features

Symptoms of tuberculosis arthritis include chronic joint pain, swelling, stiffness, and reduced range of motion in the affected joint. Fever and night sweats may also be present, especially if the patient has active tuberculosis elsewhere in the body. The onset of symptoms is usually insidious, developing over weeks to months.

Diagnosis

Diagnosis of tuberculosis arthritis involves a combination of clinical evaluation, imaging studies, and laboratory tests. Imaging studies such as X-rays, MRI, and CT scans can show characteristic changes in the joint, including joint space narrowing, bone erosion, and soft tissue swelling. Laboratory tests may include the analysis of synovial fluid obtained through joint aspiration, which can reveal the presence of Mycobacterium tuberculosis through culture or PCR testing. A definitive diagnosis is made by isolating Mycobacterium tuberculosis from the synovial fluid or tissue.

Treatment

The treatment of tuberculosis arthritis involves a combination of anti-tuberculosis medications and supportive care. The standard treatment includes a multi-drug regimen of antibiotics such as isoniazid, rifampicin, ethambutol, and pyrazinamide for a duration of at least 6 months. In some cases, surgical intervention may be necessary to drain abscesses, remove necrotic tissue, or stabilize the joint.

Prognosis

With timely and appropriate treatment, the prognosis for tuberculosis arthritis is generally good. However, delays in diagnosis and treatment can lead to joint destruction and permanent disability. Early intervention is crucial to prevent long-term complications.

Prevention

Prevention of tuberculosis arthritis involves controlling the spread of tuberculosis through public health measures such as vaccination with the BCG vaccine, prompt diagnosis and treatment of active TB cases, and screening and treatment of latent TB infections.