Sir,
COVID-19 is still an important health problem. At present, COVID-19 vaccination is recommended and accepted as the best preventive measure against COVID-19. The effect of vaccination is an interesting issue in clinical medicine. As a new vaccine, knowledge is still limited. Here, the authors would like to share data on venereal disease research laboratory (VDRL) serology after COVID-19 vaccination: The first report. The patient is a 35-year-old female diagnosed with syphilis and received complete course of penicillin therapy. VDRL serology data on this case are presented in [Table 1]. Based on this data, it might show that the vaccine might have effect of VDRL serology. A false-positive VDRL might occur. However, since this is only an observation in a single case and considered a preliminary report, further studies for getting more data are required for the final conclusion. The impact of COVID-19 on epidemiology of syphilis is sporadically reported,[1,2] but the impact of COVID-19 vaccination has never been mentioned in any literature. In fact, false-positive VDRL is a rare possible problem after vaccination. The best example is false positive following smallpox immunization.[3] To the best of our knowledge, this is the first world report on VDRL serology and COVID-19 vaccination.
Table 1.
Course of syphilis laboratory data of the patient
| VDRL titer result | TPHA result | |
|---|---|---|
| At diagnosis of syphilis | 1:16 | Reactive |
| 1 month after penicillin | 1:4 | Not test |
| 2 months after penicillin treatment | 1:2 | Not test |
| 3 months after penicillin treatment | 1:8 | Nonreactive |
| 4 months after penicillin treatment | 1:8 | Nonreactive |
| 5 months after penicillin treatment | 1:2 | Nonreactive |
The patient received the first dose of COVID-19 vaccine during the 2 and 3 months after penicillin treatment period, All laboratory tests are duplicately performed under standard method under quality control in ISO15189 certified laboratory. VDRL=Venereal disease research laboratory, TPHA=Treponema pallidum hemagglutination
This is a report on COVID-19 vaccination in a vaccine recipient with underlying syphilis. This case had a clinical history of skin lesion, (chancre) on the anogenital area, indicating possible primary syphilis in the past 15 years. There are no clinical findings in the present visit. The clinical presentation of VDRL reactivity 1:16 and treponema pallidum hemagglutination (TPHA) positivity are all suggestive of syphilis. Post-COVID vaccination, there is some rise in titer of VDRL which then again goes down. A long-term follow-up study might be useful. In the present report, a long follow-up of VDRL titers in a case with VDRL positive is presented. TPHA nonreactivity is surprising as once TPHA is positive, usually it remains positive throughout the life. However, the negative TPHA after a treatment is also reported.[4] In this case, the positive VDRL is an interesting observation. As already noted, the VDRL false positive is already reported as result from other vaccine.[3] Whether COVID-19 vaccination affects VDRL serology or not is still an interesting query. Further studies in a larger group of subjects should be conducted since there is no strong evidence in the case suggesting false-positive VDRL.
Consent
The patient gave consent for the presentation of the case for academic purposes.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understands that her name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References
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