Erythema multiforme caused by Treponema pallidum in a young patient with human immunodeficiency virus infection

Secondary Syphilis Presenting as Erythema Multiforme in the Setting of AIDS and Psoriasis

Syphilis is a highly infectious sexually transmitted infection (STI) with a multitude of presentations. The disease is known as "the great imitator" as it often presents as other chronic dermatoses, leading to a difficult and delayed diagnosis. Here, we describe the case of a 17-year-old Vietnamese male from Dong Nai Province who was initially diagnosed with psoriasis. However, upon further investigation, he was found to have concurrent secondary syphilis and psoriasis complicated by an undiagnosed human immunodeficiency virus (HIV) infection which presented clinically as generalized erythema multiforme (EM). The patient demonstrated significant improvement after being treated for syphilis and psoriasis, and he was subsequently referred to an infectious disease specialist for treatment of the underlying HIV infection.

Immunohistochemical diagnosis of human infectious diseases: a review

BACKGROUND

Immunohistochemistry (IHC) using monoclonal and polyclonal antibodies is a useful diagnostic method for detecting pathogen antigens in fixed tissues, complementing the direct diagnosis of infectious diseases by PCR and culture on fresh tissues. It was first implemented in a seminal publication by Albert Coons in 1941.

MAIN BODY

Of 14,198 publications retrieved from the PubMed, Google, Google Scholar and Science Direct databases up to December 2021, 230 were selected for a review of IHC techniques, protocols and results. The methodological evolutions of IHC and its application to the diagnosis of infectious diseases, more specifically lice-borne diseases, sexually transmitted diseases and skin infections, were critically examined. A total of 59 different pathogens have been detected once in 22 different tissues and organs; and yet non-cultured, fastidious and intracellular pathogens accounted for the vast majority of pathogens detected by IHC. Auto-IHC, incorporating patient serum as the primary antibody, applied to diseased heart valves surgically collected from blood culture-negative endocarditis patients, detected unidentified Gram-positive cocci and microorganisms which were subsequently identified as Coxiella burnetii, Bartonella quintana, Bartonella henselae and Tropheryma whipplei. The application of IHC to ancient tissues dated between the ends of the Ptolemaic period to over 70 years ago, have also contributed to paleomicrobiology diagnoses.

CONCLUSION

IHC plays an important role in diagnostic of infectious diseases in tissue samples. Paleo-auto-IHC derived from auto-IHC, is under development for detecting non-identified pathogens from ancient specimens.

Secondary syphilis presenting as erythema multiforme in a HIV-positive homosexual man: a case report and literature review

Early syphilis can rarely cause erythema multiforme-type eruptions as well as triggering erythema multiforme (EM). EM-like lesions in secondary syphilis are characterized by clinical features of EM and laboratory tests consistent with secondary syphilis and the skin histology shows predominantly a plasma cell infiltrate with the presence of treponemes. When EM is triggered by early syphilis, the skin histology shows mixed inflammatory cells usually in the absence of treponemes in the skin lesion. There may also be mixed histology with the presence of treponemes in the absence of a plasma cell infiltrate and vice versa. We describe a case of secondary syphilis presenting as EM with bullae and histology showing EM features without a plasma cell infiltrate but positive for Treponema pallidum by immunohistochemical staining. The patient was also coinfected with cytomegalovirus, human immunodeficiency virus, and anal warts. The EM eruptions resolved with treatment for secondary syphilis with benzathine penicillin G.

Erythema multiforme triggered by Treponema pallidum infection in an HIV-infected patient

We are currently facing a worldwide epidemic of syphilis. Clinical manifestations that are rarely seen have been encountered, leading the dermatologist to confront unusual clinical conditions in daily practice. Erythema multiforme triggered by syphilis is very rare and is also seldom reported in the literature. We report a case of secondary syphilis in an HIV-positive patient, whose clinical, pathologic and serologic features were consistent with the diagnosis of erythema multiforme triggered by syphilis.

Secondary Syphilis Presenting As Palmoplantar Psoriasis

In a recent past, the incidence of syphilis has increased in various geographical regions. The authors describe a case of secondary syphilis mimicking palmoplantar psoriasis.

Malignant syphilis with ocular involvement in an HIV-infected patient

Malignant syphilis is now considered a rare disease, more commonly affecting individuals with poor health, malnutrition or HIV infection. We present a 34-year-old man with HIV infection who developed multiple atypical cutaneous ulcerations, leonine facies, a scleral nodule and keratitis with visual loss. The diagnosis of malignant syphilis was delayed due to the insidious presentation, but was confirmed via immunohistochemical (IHC) staining with anti-Treponema antibodies of a skin biopsy. Significant clinical improvement was observed following a 15-day course of penicillin and tigecycline therapy. In advanced HIV disease, cutaneous manifestations are often difficult to identify and present a challenge for the clinician. Clinical manifestations of secondary syphilis vary greatly, earning the epigram of 'the great imitator'. It is important to recognize atypical presentations of syphilis, especially among HIV-infected individuals. Unlike historical cases of malignant syphilis, Treponema pallidum was found in the tissue section using IHC staining methods. We emphasize the importance of lues maligna in the differential diagnosis of HIV-infected patients with diffuse ulceronodular lesions as well as the usefulness of histological investigations and IHC studies.