[Syphilis in the context of HIV-infection--a complex disease]

A 39-year-old man complained about a slightly reddish non-itching rash evolving on his body during the last few weeks without any general symptoms. Physical examination revealed trunk-dominated roseola, papules, a few nodules with haemorrhagic crust on top, and round hyperkeratotic clavus-like lesion on the left plantar foot. In his mouth, he had a few up to 1.5 cm large erosions, and on his capillitium a diffuse alopecia.

Serologic testing for syphilis was positive with Treponema-pallidum-particle-agglutination test at 1:163840, VDRL 1:64, positive IgG-FTA-ABS and 19S-IgM-FTA-ABS tests, and a pleocytosis of the liquor. In addition, there were a co-infection with mycoplasma hominis and first diagnosis of HIV infection (CDC-stadium A1).

The patient was diagnosed as having secondary syphilis with suspicion of neurologic involvement and was therefore treated with 6x5 Mio. I.E. Penicillin G i.v. per day for 14 days after the initial application of 40 mg methylprednisolone. Under this regimen complete resolution of the skin lesions was noted over a 4 week period as well as slow re-growth of the hair. HIV infection at stadium A1 did not require antiretroviral treatment.

A non-pruritic rash should always point to the differential diagnosis of syphilis. If syphilis is diagnosed, any other sexually transmitted disease including HIV should be excluded as possible co-infection. In case of HIV, neurosyphilis can develop at an earlier stage of common syphilis.