Caused by the spirochete bacterium
Treponema pallidum, syphilis is unique in that it goes through three clinical stages if it is not treated. Primary syphilis occurs after infection at the site of inoculation and is characterized by a painless skin ulcer (“chancre”) lasting 3–6 weeks. If the infection is not appropriately addressed, syphilis progresses to its second stage, in which a diffuse, nonpruritic macular or papular rash on the extremities and trunk is the most classic symptom
[42,43][11][12]. Other symptoms in this stage are nonspecific and may include fever, headache, fatigue/malaise, myalgias, and weight loss. Femoral, inguinal, axillary, epitrochlear, and posterior cervical adenopathy are also likely. The dermatologic findings of secondary syphilis are varied, but in addition to the classic rash that is typically seen, “moth-eaten” alopecia may be present
[42,43,44,45][11][12][13][14]. Secondary syphilis may also affect other organs/systems, such as the liver (hepatitis), gastrointestinal system, musculoskeletal system (synovitis, osteitis, periostitis), kidneys (nephrotic syndrome, acute renal failure, acute nephritis), neurological system (headache, cranial nerve deficits, stroke), and eyes (anterior and posterior uveitis, optic neuritis, retinal necrosis)
[42][11]. Latent syphilis is defined as infection with
T. pallidum shown on serologic testing but without symptoms or clinical manifestations. If the infection occurred within the preceding 12 months (24 months by the World Health Organization’s definition), it is considered early latent syphilis. Infection greater than 12 (or 24) months prior defines late latent syphilis, and latent syphilis of unknown duration, although seemingly aptly named, draws ire from some clinicians given its implicit ambiguity
[46][15]. Tertiary syphilis is the symptomatic form of late syphilis and can occur in up to 40% of patients who do not receive appropriate treatment
[47][16]. Symptoms are variable but the most classic symptoms involve the cardiovascular system (aortitis), the central nervous system (general paresis, tabes dorsalis), and the formation of gummas (granulomatous, nodular lesions of any organ)
[48][17].