Radiographic aspects in individuals infected by human T-lymphotropic virus type 1 (HTLV-1) with joint pain.

BACKGROUND

Joint pain in the absence or with little synovitis is observed in a large percentage of HTLV-1 infected subjects. As the virus infect CD4 + and CD8 + positive, macrophages and B cells an exaggerated production of pro-inflammatory cytokines is detected in these patients. However, the possible association of HTLV-1 infection with autoimmune diseases has not been documented definitively and the clinical characteristics of HTLV-1 associated arthropathy has not been defined. The objective this study is to describe clinic and radiographic features in HTLV-1-infected individuals with complaints of joint pain.

METHODS

Cross-sectional study enrolling HTLV-1-infected individuals with chronic joint pain, aged up to 75 years, both genders and seronegative controls with osteoarthritis. All participants underwent conventional radiography of the hips, knees and ankles.

RESULTS

Eighty-one HTLV-1 infected patients and 30 subjects with osteoarthritis participated in the study. Polyarticular and symmetrical arthritis prevailed in the HTLV-1 positive group (54%), while oligoarticular and asymmetrical (44%) were more common in controls (p < 0.05). The frequency of enthesophytes (90%) in HTLV-1-infected patients was greater than in the control group (73%) (p < 0.05). Radiographic features were similar in HTLV-1 carriers and in patients with probable or definite HTLV-1 associated myelopathy. The presence of enthesophytes in the absence of joint space reduction or osteophytes was only observed in HTLV-1-infected individuals (p < 0.001). Magnetic resonance imaging of the ankles of five HTLV-1-infected patients and five controls demonstrated a higher frequency of enthesitis, bursitis and osteitis in the HTLV-1 infected group.

CONCLUSION

HTLV-1-associated arthropathy is clinically characterized by symmetrical polyarthralgia and the main radiological finding is the presence of enthesophytes in the absence of osteophytes and joint space narrowing.