Positive Fluorescent Treponemal Antibody Absorption Test in Cerebrospinal Fluid of Nonsyphilitic Persons Infected With Human Immunodeficiency Virus

To the Editor.—  The fluorescent treponemal antibody absorption (FTA-ABS) test is widely regarded as sensitive, outstanding, and specific for antitreponemal antibodies. Three weeks after infection, antitreponemal antibodies can be demonstrated in the serum by this test. So-called nonspecific results are rare and are associated with autoimmune diseases, diabetes mellitus, liver cirrhosis, and pregnancy.^1-4False-positive results account for 6% to 10% of positive FTA-ABS test results.^5-7 The occurrence of nonspecific syphilis test results in cerebrospinal fluid is estimated to be extraordinarily rare.⁸ However, there is a report of positive FTA-ABS test results in the cerebrospinal fluid of a patient suffering from spinal ependymoma, whereas other tests for syphilis yielded negative results.⁹In our investigation of cerebrospinal fluids from patients infected with human immunodeficiency virus, we performed the FTA-ABS, VDRL, and Treponema pallidum hemagglutination tests. Because the FTA-ABS test on cerebrospinal fluid is not recognized as a standard