TP 151 Dual Dried Tube Specimen for Quality Control for Syphilis and HIV Rapid Tests: Does It Work?

Tuesday, June 10, 2014
Exhibit Hall
Marina Chiappe, Member of ALACITS PE-0831, Doris Lopez-Torres, Member of ALACITS ID: PE-0842 and Patricia Garcia, President of ALACITS ID: PE-0011, 1School of Public Health and Administration, Universidad Peruana Cayetano Heredia, Lima, Peru, 2School of Public Health and Administration, Universidad Peruana Cayetano Heredia, Lima

Background:  The use of point-of-care tests (POCTs) for infectious diseases such as HIV and Syphilis has expanded and there are now several rapid tests on the market.  However, some tests lack good standards and regulatory approval. Additionally, quality control for POCTs is still a significant challenge. Laboratories regularly use serum samples for the quality control of syphilis and HIV tests. However, it is infrastructure-intensive and costly to maintain these samples. Therefore, we tested the effectiveness of dual Dry Tube Specimens (DTS) for the quality control of HIV and syphilis rapid tests.

Methods:  We used dried tube specimen (DTS) and allocated different antibodies concentrations for the diagnosis of HIV and syphilis in the same tube. DTS uses a small volume (20uL) of serum per tube. It is colored and then dried overnight. It is stable at room temperature for at least one month. It can then be rehydrated at the location where the quality control will take place. We compared the DTS with the gold standard. Our positive gold standard for syphilis was RPR and rapid syphilis test positives and our positive gold standard for HIV was rapid HIV test positives. Our negative gold standard for HIV and syphilis were rapid test negatives. This was a laboratory-based evaluation.

Results:  We found 100% specificity and 100% sensitivity when using DTS to carry out the quality control of syphilis and HIV rapid test positives, respectively. In other words, DTS is equivalent to the gold standard.

Conclusions:  We recommend the use of syphilis and HIV DTS panels for external quality control in the field. DTS is easy to prepare, simple to distribute and perform, and should improve syphilis and HIV rapid test quality control programs.