False Negative Serologic Tests for Syphilis in HIV-Infected Patient

 

Clinical findings:

(1) severe immunosuppression with AIDS

(2) high risk sexual behavior (especially in an area with a high rate of syphilis) or contact with someone who engages in high risk sexual behavior

(3) history of or clinical findings compatible with primary or secondary syphilis (chancre, generalized rash, etc)

 

Unfortunately many of the findings of secondary syphilis (malaise, fever, weight loss, lymphadenopathy) can be caused by other diseases that the AIDS patient is susceptible to.

 

Laboratory findings:

(1) weak, negative or atypical reactions in serologic tests for syphilis (RPR, VDRL, antibody, etc)

(2) weak, negative or atypical reactions with other serologic tests

(3) low levels of serum immunoglobulins

(4) biopsy show a lymphoplasmacytic perivasculitis

(5) positive silver impregnation stain (Warthin-Starry) for spirochetes

(6) positive PCR