Akademik Veri Yönetim Sistemi
2021 The European Congress of Clinical Microbiology and Infectious Diseases (31st ECCMID), Amstetten, Avusturya, 9 - 12 Temmuz 2021
Background Syphilis still remains a great problem for all over the world. Although there are
many serological tests for diagnosis, none of them is gold-standard method. The aim of the study
is to evaluate the performance of chemiluminescence immunoassay (CIA), rapid plasma reagin
(RPR) and Treponema pallidum Hemagglutination Assay (TPHA) tests used in the diagnosis of
syphilis with together examine the clinical data of the patients.
Methods Patients whose syphilis serology was evaluated in the Kocaeli University Hospital
between December 2019-January 2021 were included in the study. Serum samples were tested
with RPR, CIA, TPHA. RPR in traditional algorithm and CIA in reverse algorithm were used as
screening tests. TPHA was used as a confirmation test in both algorithms. The sensitivity,
specificity, and positive-negative predictive values of the CIA, RPR, and TPHA were determined by using
the clinical data as a reference.
Results Syphilis serology of 3577 patients was evaluated. According to clinical data, 152
(4.24%) patients were diagnosed with syphilis and 71 (46.7%) of them had HIV infection. Of the
syphilis patients, 120 (78.9%) were male, 32 (21.1%) female, and the mean age was 40.79 (range:17-
84). According to clinical data, the performance of tests was shown in Table 1. The reverse
algorithm detected false-positive results
algorithm, and false-positive results were detected with CIA in 14 patients (Table 2). Seventeen
patients who were CIA and TPHA positive and RPR negative had a history of syphilis. False negativity
of TPHA was found in 9 patients with a history of syphilis (Table 3).
Conclusions Syphilis cases increased approximately 3 times, HIV cases 1.5 times between
2016-2019 in our country. Therefore, correct diagnosis and treatment of syphilis are very
important. In the study, it was seen that it is important to use treponemal and nontreponemal
tests together and to evaluate them in light of clinical data in the diagnosis of syphilis. If the
CIA is positive, it was considered important to confirm the result with a different treponemal test.
It should be kept in mind that false-positivity causes socio-psychological problems, and unnecessary
treatment. In addition, false negativity causes the spread of other sexually transmitted diseases
in society.