b. Venereal Disease Research Laboratory (VDRL) test
c. Nucleic acid amplification test for Chlamydia
d. Blood cultures
e. Biopsy of perianal lesions
The diffuse rash involving palms and soles would in itself suggest the possibility of secondary syphilis. The hypertrophic, wartlike lesions around the anal area, called condyloma lata, are specific for secondary syphilis. The VDRL slide test will be positive in all patients with secondary syphilis.
Rash and lymphadenopathy would not be found if the perianal lesions were due to HPV. Chlamydia infections cause urethritis with mucopurulent discharge from the penile meatus but not the systemic symptoms or hypertrophic skin changes. Blood cultures might be drawn to rule out bacterial infection such as chronic meningococcemia; however, the clinical picture is not consistent with a systemic bacterial infection. Biopsy of the condyloma is not necessary in his setting, as regression of the lesion with treatment will distinguish it from genital wart (condyloma acuminatum) or squamous cell carcinoma.