CASE 1 A 45-year-old man infected with the human immunodeficiency virus (HIV) presented with a 3-month history of violaceousovalmaculesandpapulesonthetrunkandextremities (Figure 1) as well as multiple lichenoid papules over the metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints and elbows (Figure 2). Brownish-red scaly patches were observed onthepalms.HismostrecentCD4cellcountwas158cells/ mL, and his viral load was 175102 copies/mL. The patient’s history was significant for Kaposi sarcoma, treated with liposomal doxorubicin, and syphilis, which was treated 15 years earlier with 3 courses of intramuscular penicillin G. The patient had recently developed hypercholesterolemia, induced by highly active antiretroviral therapy, and subsequently had a myocardialinfarction.Secondarysyphiliswassuspected,butfindings from the rapid plasma regain (RPR) test, performed with appropriate dilution to rule out a prozone reaction, were negative. Biopsy specimens of the abdomen and dorsal surface of the right hand both revealed a bandlike and perivascular lymphohistiocytic infiltrate with scattered plasma cells, acanthosis, and exocytosis (Figure 3). WarthinStarry staining revealed several silver-impregnated spirochetalorganisms(Figure 4).Spirocheteswerenotseen on examination of the retina or cerebrospinal fluid. A treponemal-specific serologic test, such as the fluorescent treponemal antibody absorption test, was deferred because this patient had a history of syphilis infection. The patient experienced rapid and complete resolution of his cutaneous disease with 3 weekly courses of intramuscular penicillin G at a dose of 2.4 million IU. CASE 2 A 36-year-old HIV-positive man presented to the dermatology clinic with a 1-year history of pruritic weeping buttock lesions. He had been previously treated by his primary care physician with topical corticosteroids and had completed a 7-day course of famciclovir with