Abstract: A 76-year-old woman has got both lower limbs petechia and ecchymosis for 1 month, edema for 6 days and fever for 3 days. The patient suffered from
purpura of both lower limbs, edema, arthralgia, recurrent fever, kidney
damages, serositis, progressive reduction of platelet, moderate anemia and
lymphadenopathy during the last two months. Laboratory examinations showed
that her whole blood cells, platelet counts, serum albumin level and
complements were all decreased and her titres of antibodies to
double-stranded DNA (ds-DNA) were high. The patient had unequivocal SLE as
she fulfilled seven American Rheumatism Association criteria (1997). Enzyme
linked immunosorbent assays (ELISAs) for human immunodeficiency virus (HIV)
was positive, while negative by Western blot analysis. A diagnosis of
Systemic lupus erythematosus was made in view of the above findings. Because
of the presence of autoantibodies and cross-reactivity, diagnosis of HIV
infection should be cautious in patients with systemic autoimmune disease.
The use of rigorous confirmatory testing by western blot analysis or
immunofluorescence assay is therefore mandatory. More sensitive assays may
be necessary to confirm the presence of HIV infection, such as gene
amplification by the polymerase chain reaction, virus isolation and
cultivation, the CD4 cell count and the ratio of CD4/CD8.
Keywords: Human immunodeficiency virus, systemic lupus erythematosus, false positive, case reports
