Race for the Case answers

Race for the Case – Summer 2023 by Shiri Nawrocki, MD, and Pooja Srivastava, MD 

A 42-year-old male with past medical history significant for HIV with medication noncompliance, methamphetamine use disorder, and chlamydia, presents with a pruritic eruption that has been ongoing for four months. The patient reports that the rash started on his arms and then rapidly spread to the rest of his body. He denies clearance of any lesions since onset of the rash and reports continued development of new lesions. He denies a personal or family history of any prior dermatologic conditions. Review of systems is significant for an unintentional 15-pound weight loss over two years. 

1. What is the most likely diagnosis and which histologic findings suggestive of the diagnosis are shown in the slide?
The clinical photographs demonstrate ulceronodular syphilis, or lues maligna, which is a severe form of secondary syphilis. The punch biopsy shows psoriasiform epidermal hyperplasia and a superficial and mid perivascular and lichenoid inflammatory cell infiltrate (Hematoxylin and Eosin stain, 2x). The inset shows several plasma cells and occasional eosinophils (Hematoxylin and Eosin stain, 20x).

2. Describe the clinical findings of the secondary stage of this condition.
Secondary syphilis classically presents with a generalized papulosquamous or maculopapular eruption. Papules and plaques with collarettes of scale may occur on the palms and soles. Other clinical findings may include condylomata lata in the anogenital region, condylomata lata-like lesions in the oropharynx, hypopigmented macules on the neck, patchy “moth-eaten” alopecia, and split papules (syphilitic perlèche).

3. Describe the two categories of serologic tests that can assist with diagnosis. Which test can be used to monitor treatment response?
The serologic tests can be divided into treponemal and non-treponemal. Treponemal tests include FTA-ABS and MHA-TP, while non-treponemal tests include RPR and VDRL. Non-treponemal tests are useful in screening and monitoring treatment response as their titers become negative after successful treatment. Treponemal tests have very high specificity, making them useful in confirming positive non-treponemal test results.

4. What is treatment of choice for the secondary stage of this condition?
Penicillin G is the treatment of choice for all stages of syphilis. One intramuscular dose of 2.4 million units of benzathine penicillin is the preferred treatment for secondary syphilis. In penicillin-allergic patients, doxycycline, tetracycline, or ceftriaxone should be utilized.

References
Alikhan, A, Hocker, TLH. Infectious Diseases. In: Alikhan, A, Hocker, TLH, eds. Review of Dermatology. Elsevier; 2017:301-302.
Hicks, C, Clement, M. “Syphilis: Treatment and Monitoring.” UpToDate, 15 Mar 2023.
Stary, G, Stary, A. Sexually Transmitted Infections. In: Bolognia JL, Schaffer JV, Cerroni L, eds. Dermatology. 4th ed. Elsevier; 2018:1447-1459.