Case of the Month

Syphilis 400x, with plasma cells

Syphilis 630x, with spirochete stain

57 year-old man with an explosive eruption of 2 weeks duration as depicted here. Mildly to not very pruritic. No palmar, plantar or oral lesions. No history of genital lesions.

What's Your Diagnosis?

Diagnosis: SYPHILIS

(Dermatopathologic report by Eric Jacobson MD, dermatopathologist)

Micro: Sections show a psoriasiform and lichenoid infiltrate with prominent histiocytes and plasma cells in the superficial and mid-dermis. There is endothelial swelling as well. A spirochete immunohistochemical stain demonstrates the organisms in the epidermis, superficial dermis and associated with the reactive endothelium. These are the classic histopathologic findings of: secondary syphilis.

Soles of a patient with secondary syphilis (not the patient in this case) but it is characteristic of what has been described as “Copper pennies” seen on the palms and soles of patients with secondary syphilis. Syphilis has also been called “Lues” as a result of many hospitals having open wards and as the attending’s were discussing the case with the residents, it would not alarm or stigmatize the patient or the other patients within earshot in the open wards.

Syphilis

Definition
An inflammatory process, caused by the spirochete Treponema pallidum, that tends to evolve through three stages, namely, primary (typified usually by a solitary chancre), secondary (characterized by widespread macules and papules on skin and mucous membranes in conjunction with signs and symptoms of systemic disease), and tertiary (manifested by gummas in the skin and destructive lesions also in the bones, eyes, brain, and elsewhere, resulting in debilitation and often death).

Diagnostic Tests
Demonstration by darkfield microscopy of spirochetes in the exudate of a lesion. Serologic tests for syphilis, including RPR, Elisa, and histologic evaluation with special stains, as seen in our case, here.

Course
Individual lesions of secondary syphilis have different names depending on the stage of the disease. The chancre of primary syphilis usually presents itself as an ulcerated papule or nodule that heals in weeks. The papules of secondary syphilis often are scaly and widespread, and may last for weeks or even months before they disappear. A gumma of tertiary syphilis usually is an ulcerated plaque in the center of which may be an atrophic scar. Only gummas are permanent, although a chancre may heal with a scar and some lesions of secondary syphilis with macular atrophy.

Unifying Concept
All of the findings in the skin in syphilis are a direct consequence of the effects of spirochetes of Treponema pallidum and the immunologic response of the host to them. A chancre teems with spirochetes, as do early lesions of secondary syphilis on mucous membranes, especially condylomata lata. Early lesions of secondary syphilis in the skin are replete with spirochetes, whereas late lesions of secondary syphilis contain few or none of them. In a gumma, spirochetes may be present, but they are detected with extraordinary difficulty. Although spirochetes may be found in the dermis of a chancre or in a papule of secondary syphilis, they are seen best in an epidermis that has been exposed to an immunoperoxidase stain specific for Treponema pallidum. The spirochetes also can be demonstrated readily with specialized silver stains such as those named eponymically for Warthin and Starry, for Steiner, and for Levaditi.

When sections of tissue of a chancre are studied by conventional microscopy, an ulcer is seen and beneath it is a dense, somewhat diffuse, mixed in ilt ate of inflammatory cells in which plasma cells abound. In papules of secondary syphilis, there is a superficial and deep perivascular infiltrate composed mostly of histiocytes and plasma cells, and those cells often are arranged also in lichenoid pattern beneath a pallid psoriasiform epidermis. Neutrophils present within the epidermis of secondary syphilis are an indication that that surface epithelium houses innumerable spirochetes.

As the process of secondary syphilis evolves, neutrophils disappear from lesions and epithelioid histiocytes appear in ever greater numbers, eventually forming collections (granulomas). At that granulomatous stage, spirochetes no longer can be found. A gumma, as its name denotes, is characterized by gummatous inflammation in which necrosis of inflammatory cells and degeneration of collagen is extensive, that debris being surrounded in turn by granulomatous inflammation joined by a lymphoplasmacytic infiltrate and by fibroplasia.

Syphilis has traditionally been regarded by clinicians to be a “great mimicker”; the same can be said by histopathologists.

Therapy
Penicillin is the drug of choice at all stages. In primary, secondary, and early latent syphilis, intramuscular benzathine penicillin (2.4 million units) as a single dose, or tetracycline or erythromycin for 14 days, and, in late syphilis, excluding neurosyphilis, intramuscular benzathine penicillin or oral tetracyclines for 21 days.

Reference:

A CLINICAL ATLAS OF 101 COMMON SKIN DISEASES With Histopathologic Correlation A. BERNARD ACKERMAN, HELMET KERL, JORGE SANCHEZ, YING GUO, ANGELIKA HOFER, PAUL KELLY, TETSU KIMURA, GIOVANNI BORRONI, CHARLES CRUTCHFIELD, VOLKER STEINKRAUS, WOLFGANG WEYERS