Malignant syphilis (MS) is a rare form of secondary syphilis which is frequently associated with human immunodeficiency virus (HIV) infection.1 Since the beginning of the HIV epidemic, the incidence of MS has been steadily rising, making it a disease of vital recognition for any patient with suspicious cutaneous lesions. MS, also referred in the literature as syphilis maligna praecox, lues maligna, or rupioid syphilis, is defined as the presence of pleomorphic multiple round to oval papules, papulopustules, or nodules with ulceration, without central clearing, and occasionally exhibit a lamellate brown to black rupioid crust. This disease is characterized by marked prodromal constitutional symptom, such as fever, malaise, myalgia, headache, and weight changes over the span of 4 weeks before the appearance of skin lesions.1
Characteristic morphology of lesions, positive serological tests for syphilis, characteristic histopathology, and resolution of lesions following administration of penicillin therapy confirmed the clinical diagnosis of MS.1 Fisher et al.2 defined the classical diagnostic criteria for MS as: compatible macroscopic and microscopic skin lesions, high serology titer, Jarisch-Herxheimer reaction (JHR) upon starting antibiotic treatment, and rapid clinical resolution with treatment. Here we report a case of MS and this was the initial presentation of HIV infection.
A 35-year-old married male was admitted to the dermatology and venereology clinic of Wahidin Sudirohusodo Hospital, Makassar, South Sulawesi, Indonesia, with a 1-month history of extensive erythematous nodular rash affecting the axilla, trunk, back, inguinal, penis, and soles accompanied with fever and malaise. Some lesions were ulcerated with annular configuration (Fig. 1A–D). The lesions were painful and itchy with brown-black thick crust. No mucosal lesions were seen. He reported history of sexual intercourse with more than one partner. Past medical history was significant for gonorrhea, which was successfully treated and cured.
On clinical examination the patient had a temperature of 38.2 °C, while other vital signs were within normal limit. He also complained of general malaise and headache. A skin biopsy was taken from the back and histological examination with hematoxylin and eosin staining showed epidermal hyperplasia with hyperkeratosis and acanthosis. In the dermis, lymphocytes, and histiocytes (Fig. 2A) and very dense perivascular and periadnexal plasma cells (Fig. 2B) were observed. These findings were consistent with syphilis.
Laboratory investigation revealed normal complete blood count, reactive rapid plasma reagin (1:128), and positive Treponema pallidum hemagglutination (1:5,120). The Hepatitis B surface antigen and anti-hepatitis C virus were non-reactive. Enzyme linked immunosorbent assay for HIV was reactive with CD4 cell count of 291 cells/mm3.
With the above clinical, laboratory, and histopathologic data taken into consideration, a diagnosis of MS with HIV infection was made. The patient was decided to be treated with intramuscular injection of 2.4 million units of benzathine penicillin G for three consecutive weeks. He was also treated with antiretroviral therapy with tenofovir 300 mg, lamivudine 300 mg, and efavirenz 600 mg per day. Topical fusidic acid cream was also applied on ulcerative lesions to avoid bacterial superinfection. He responded very well to benzathine penicillin G and no JHR was seen during treatment. On follow-up visit, 1 week after the third injection, the patient presented with post-inflammatory hyperpigmentation and a view residual scars (Fig. 1E–H). The patient gave his agreement for case publication.
HIV infection may make clinical manifestations of syphilis more severe and/or atypical. Humoral and cellular immunity against Treponema pallidum depend on the stage of HIV infection and host defence; impairment in immunity may lead to changes in the clinical presentations and natural course of syphilis, increased number of syphilis lesion and degree of infectiousness, and shortened incubation time. A treponemal infection may act as a facilitator or aggravator for HIV transmission from co-infected patients.3 Co-infection of syphilis and HIV alters the course of both diseases. The clinical impact of HIV and syphilis co-infection is bidirectional; HIV alters the course of syphilis and syphilis also appears to adversely impact HIV disease progression and transmissibility. It is also associated with decreased CD4+ T-cell counts and increased HIV viral loads.4 Immunologic events that facilitate the development of MS are unknown, but it is reasonable to postulate that the loss of helper T cells is responsible. One study found 80% of HIV patients with MS had a CD4 count greater than 200 cells/mm3.5 Our patient's presenting CD4 count was 291 cells/mm3. These findings suggest that people with acute HIV infection, whose CD4 count is still relatively high, maybe an at-risk population.
Although MS was described well before the HIV pandemic, more cases of MS have been described in people with HIV infection. Persons living with HIV/acquired immunodeficiency syndrome are 60 times more likely to present with this form of syphilis.5 The onset of MS is characterized by prodromal symptoms composed of arthralgia, malaise, and fever. The lesions are characterized by erythematous-violaceous or reddish-coppery ulcerated papules, nodules, or blisters, followed by necrosis of the center of the lesion that may give rise to rupioid crusts that resemble an oyster shell. In some cases, they form small ulcers with well-defined edges, covered with purulent secretion without perilesional inflammatory reaction. The lesions mainly affect the trunk and extremities, but involvement of the mucosae, palms, soles, and scalp is also common.6
Fisher et al.2 defined the classical diagnostic criteria for MS as compatible macroscopic and microscopic skin lesions, a high serology titer, JHR upon starting antibiotic treatment; and rapid clinical resolution with treatment. Based on the clinical presentation of the disease, darkfield microscopy performed on the fluid obtained from the lesional skin, syphilis serology, and histopathology characterized by dermal plasma cell admixed with lymphocytes, histiocytes, and neutrophilic venulitis is describe as a pattern of syphilis maligna, but spirochetes are infrequently found.7 In this case, we were not able to identify spirochetes in dark-field microscopy; however, syphilis serology was highly positive and the histopathology was typical with the findings of numerous plasma cell infiltrates in the dermis. Intramuscular injection of benzathine penicillin G 2.4 million units weekly for three consecutive weeks is the recommended treatment option for MS. As has been previously described in literature our patient also responded very quickly to the antibiotic therapy with Benzathine-penicillin G.
While JHR is one of the diagnostic criteria in MS as proposed by Fisher has been widely reported in several studies and case reports, Bjekić8 and Fustà-Novell et al.9 have also described MS patients with no JHR. JHR is an acute febrile inflammatory reaction that happens after antibiotic treatment of syphilis especially as well as of other spirochetal infections. The symptoms include fever, chills, headache, myalgias, exacerbation of cutaneous lesions, tachycardia, and hyperventilation during the first 24 hours after the treatment. Our case exhibited a similar phenomenon, where although both the treponemal and non-treponemal titers were high, no JHR occurred upon administration of intramuscular Benzathine-penicillin G. However, the absence of this reaction was not considered a reason to rule out a diagnosis of MS, nor did it appear to have any bearing on the specific clinical presentation.
In conclusion, the diagnosis of MS should be considered in all HIV-infected individuals with noduloulcerative skin lesions. This approach might avoid unnecessary efforts or more complex investigations in such patients.
. Rao AG, Swathi T, Hari S, et al. Malignant syphilis in an immunocompetent adult male. Indian J Dermatol 2017;62(5):524–527. doi:10.4103/ijd.IJD_733_16.
. Fisher DA, Chang LW, Tuffanelli DL. Lues maligna. Presentation of a cas and a review of the literature. Arch Dermatol 1969;99(1):70–73. doi:10.1001/archderm.99.1.70.
. Ramos-E-Silva M, Secchin P, Trope B. The life-threatening eruption in HIV and immunosuppression. Clin Dermatol 2020;38(1):52–62. doi:10.1016/j.clindermatol.2019.10.014.
. Tambe S, Zambare U, Nayak C. Nodulo-ulcerative and erythrodermic secondary syphilis in human immunodeficiency virus-infected individuals. Int J STD AIDS 2019;30(5):505–508. doi:10.1177/0956462418815310.
. Mohan GC, Ali RA, Isache CL, et al. Malignant syphilis: ostraceous, ulceronecrotic lesions in a patient with human immunodeficiency virus. Dermatol Online J 2017;23(1):13030/qt3ps899bh. doi:10.5070/D3231033673.
. Ortigosa YM, Bendazzoli PS, Barbosa AM, et al. Early malignant syphilis. An Bras Dermatol 2016;91(5 Suppl 1):148–150. doi:10.1590/abd1806-4841.20164491.
. Yamashita M, Fujii Y, Ozaki K, et al. Human immunodeficiency virus-positive secondary syphilis mimicking cutaneous T-cell lymphoma. Diagn Pathol 2015;10:185. doi:10.1186/s13000-015-0419-5.
. Bjekić M. Lues maligna as an initial presentation of underlying HIV infection in a homosexual man. Serbian J Dermatology Venereol 2017;9(4):159–162. doi:10.1515/sjdv-2017-0018.
. Fustà-Novell X, Morgado-Carrasco D, Barreiro-Capurro A, et al. Syphilis maligna: a presentation to bear in mind. Actas Dermosifiliogr 2019;110(3):232–237. doi:10.1016/j.ad.2018.02.024.