From the Guidelines
An individual with a negative VDRL test but positive TPHA test without clinical symptoms of syphilis can generally fit to work. This serological pattern typically indicates either successfully treated past syphilis or late latent syphilis, as supported by studies such as those by Gibowski et al [17@] and McMillan and Young [20@], which discuss the sensitivity of VDRL in early latent syphilis. In late latent syphilis, the VDRL (a non-treponemal test) may become negative while the TPHA (a treponemal-specific test) remains positive for life after infection, as noted in various studies including those on syphilis laboratory guidelines [1@]. Without clinical symptoms, this person is not considered infectious and poses no risk to coworkers.
Key points to consider:
- The sensitivity of VDRL in early latent syphilis ranges from 82.1% to 100% [17@, 20@, 27@], indicating that a negative VDRL does not rule out syphilis but suggests late latent syphilis if TPHA is positive.
- The management of such cases involves consulting a healthcare provider for proper evaluation, which may include additional testing like RPR or FTA-ABS to confirm the diagnosis.
- If late latent syphilis is diagnosed, treatment with benzathine penicillin G 2.4 million units IM weekly for three weeks would be recommended, though this wouldn't affect work fitness.
- It's crucial for the healthcare provider to review the person's medical history to determine if they received adequate treatment for syphilis in the past, as this impacts the interpretation of current serological results.
Given the information and the context of real-life clinical medicine, prioritizing morbidity, mortality, and quality of life, the individual's ability to work is not compromised by their serological status alone, assuming no clinical symptoms of active syphilis are present. However, a thorough medical evaluation is necessary to confirm the diagnosis and ensure appropriate management.
From the Research
Syphilis Diagnosis and Treatment
- The diagnosis of syphilis is dependent mainly on serological tests, including the VDRL and TPHA tests 1.
- A negative VDRL test with a positive TPHA test can occur, and it is essential to consider the clinical symptoms and medical history of the patient 2.
- The TPHA test is a specific antibody test used to confirm the diagnosis of syphilis, while the VDRL test is a non-treponemal test used for screening 1, 2.
Interpretation of Test Results
- A positive TPHA test result indicates the presence of treponemal antibodies, which can be found in patients with syphilis 1, 3.
- A negative VDRL test result with a positive TPHA test result can be seen in patients with late-stage syphilis or in those who have been treated for syphilis 2, 4.
- The interpretation of test results should be done in conjunction with clinical symptoms and medical history to ensure accurate diagnosis and treatment 1, 5.
Fitness to Work
- There is no direct evidence to suggest that a person with a negative VDRL test and a positive TPHA test result, without clinical symptoms of syphilis, is unfit to work 1, 2, 3, 4, 5.
- However, it is essential to consider the individual's overall health and medical history to determine their fitness to work.