What role do autoantibodies have in HIV associated rheumatic syndromes?
In untreated HIV-positive patients, the most common laboratory abnormalities are a polyclonal gammopathy in up to 45%, low-titer rheumatoid factor (RF) and antinuclear antibodies (ANAs) in up to 20%, and IgG anticardiolipin antibodies in over 90% of patients. Anticardiolipin antibodies are rarely of clinical significance since they are not associated with anti β2-glycoprotein I antibodies. Double-stranded DNA antibodies are rare. Cryoglobulins can occur in HIV patients with and without coexistent hepatitis C infection. Both cytoplasmic and perinuclear antineutrophil cytoplasmic antibodies have been described, although without characteristic vasculitis. Therefore, although autoantibodies are common, there is no clear correlation with developing a particular rheumatic syndrome. Patients presenting with arthralgias and one of these autoantibodies may be initially misdiagnosed as having a particular rheumatic disease and not an HIV infection. Following ART, antibody titers may resolve or decrease and, therefore, be less common in the post-ART era. The erythrocyte sedimentation rate (ESR) can be chronically elevated in patients with HIV, even following consistent use of ART. Thus in patients with HIV and concurrent rheumatic disease, the ESR value should be interpreted with caution and may not correlate with rheumatic disease activity.