Differential Diagnosis for a 22-year-old Primigravid Woman with Positive VDRL and Fluorescent Treponemal Antibody Absorption Test
- Single most likely diagnosis:
- Syphilis: The patient's positive VDRL test, which is a screening test for syphilis, followed by a positive confirmatory fluorescent treponemal antibody absorption test, strongly suggests syphilis as the most likely diagnosis. The presence of syphilis in pregnancy is a significant concern due to the potential for congenital syphilis, which can lead to severe fetal complications.
- Other Likely diagnoses:
- False-positive test results: Although less likely given the confirmatory test, false-positive results can occur, especially with the VDRL test. Conditions such as autoimmune diseases, certain infections, or recent vaccinations can cause false-positive results.
- Previous treated syphilis: The patient could have been previously treated for syphilis, which would result in a positive treponemal test (since these tests remain positive for life after infection) but does not necessarily indicate current infection.
- Do Not Miss diagnoses:
- Congenital syphilis: This is a critical diagnosis not to miss because it can have severe consequences for the fetus, including birth defects, stillbirth, or death shortly after birth. Prompt treatment of the mother can prevent congenital syphilis.
- Other sexually transmitted infections (STIs): Given the patient's history of syphilis, it is crucial to test for and rule out other STIs, such as HIV (which has been done in this case), gonorrhea, and chlamydia, as they can also have significant implications for pregnancy and fetal health.
- Rare diagnoses:
- Yaws or other treponematoses: These are rare diseases caused by other treponemes that can cause positive results on treponemal tests. However, they are less likely in this context given the patient's presentation and the specific tests used.
- Autoimmune disorders: Certain autoimmune conditions can cause false-positive results on non-treponemal tests like the VDRL, but this would not explain the positive confirmatory treponemal test.