Differential Diagnosis for False Positive VDRL with Negative FTA-ABS
- Single Most Likely Diagnosis + Acute viral infections (e.g., mononucleosis, hepatitis): These conditions can cause a false-positive VDRL due to the production of heterophile antibodies that interfere with the test.
- Other Likely Diagnoses + Autoimmune disorders (e.g., lupus, rheumatoid arthritis): Patients with autoimmune diseases may produce antibodies that cross-react with the VDRL test, leading to false-positive results. + Pregnancy: False-positive VDRL results can occur in pregnant women due to changes in immune function and antibody production. + Intravenous drug use: Individuals who inject drugs may be at risk for false-positive VDRL results due to the introduction of contaminants or other substances that interfere with the test.
- Do Not Miss Diagnoses + Lyme disease: Although less common, Lyme disease can cause a false-positive VDRL result, and missing this diagnosis could lead to delayed treatment and potentially severe consequences. + Syphilis with prozone phenomenon: In some cases, patients with syphilis may produce high levels of antibodies that interfere with the VDRL test, leading to a false-negative FTA-ABS result. This is a critical diagnosis to consider, as untreated syphilis can have severe consequences.
- Rare Diagnoses + Leptospirosis: This rare bacterial infection can cause a false-positive VDRL result, although it is an uncommon cause of this phenomenon. + Relapsing fever: This rare condition, caused by certain species of Borrelia, can also lead to false-positive VDRL results in some cases.