Neurosyphilis

Neurosyphilis refers to infection of the central nervous system in a patient with syphilis and can occur at any stage. The majority of neurosyphilis cases have been reported in HIV-infected patients. Meningitis is the most common neurological presentation in early syphilis. Tertiary syphilis symptoms are exclusively neurosyphilis, though neurosyphilis may occur at any stage of infection. Neurosyphilis refers to infection of the central nervous system in a patient with syphilis and can occur at any stage. The majority of neurosyphilis cases have been reported in HIV-infected patients. Meningitis is the most common neurological presentation in early syphilis. Tertiary syphilis symptoms are exclusively neurosyphilis, though neurosyphilis may occur at any stage of infection. To diagnose neurosyphilis, patients undergo a lumbar puncture to obtain cerebrospinal fluid (CSF) for analysis. The CSF is tested for antibodies for specific Treponema pallidum antigens. The preferred test is the VDRL test, which is sometimes supplemented by fluorescent treponemal antibody absorption test (FTA-ABS). Historically, the disease was studied under the Tuskegee study, which was one of the most notable examples of scientific misconduct in history. The study was done on approximately 400 African-American men with untreated syphilis were followed from 1932 to 1972 and compared to approximately 200 men without syphilis. The study began without informed consent of the subjects and was continued by the United States Public Health Service until 1972. The researchers failed to notify and withheld treatment for patients despite knowing penicillin was found as an effective cure for neurosphyilis. After four years of follow up, neurosyphilis was identified in 26.1% of patients vs. 2.5% of controls. After 20 years of followup, 14% showed signs of neurosyphilis and 40% had died from other causes. Research practices were changed, in part in response to the Tuskegee study, with the passing of the National Research Act in 1974, the establishment of institutional review boards and informed consent practices, and a presidential apology issued in 1997. The signs and symptoms of neurosyphilis vary with the disease stage of syphilis. The stages of syphilis are categorized as primary, secondary, latent, and tertiary. It is important to note that neurosyphilis may occur at any stage of infection. Meningitis is the most common neurological presentation in early syphilis. It typically occurs in the secondary stage, arising within one year of initial infection. The symptoms are similar to other forms of meningitis. The most common associated with neurosyphilitic meningitis is cranial nerve palsy of the facial nerve. Nearly any part of the eye may be involved. The most common form of ocular syphilis is uveitis. Other forms include episcleritis, vitritis, retinitis, papillitis, retinal detachment, and interstitial keratitis. Meningovascular syphilis usually occurs in late syphilis but may affect those with early disease. It is due to inflammation of the vasculature supplying the central nervous system, that results in ischemia. It typically occurs about 6-7 years after initial infection and it may affect those with early disease. It may present as stroke or spinal cord infarct. Signs and symptoms vary with vascular territory involved. The middle cerebral artery is most often affected. Parenchymal syphilis occurs years to decades after initial infection. It presents with the constellation of symptoms known as tabes dorsalis, because of a degenerative process of the posterior columns of the spinal cord. The constellation includes Argyll Robertson pupil, ataxic wide-based gait, paresthesias, bowel or bladder incontinence, loss of position and vibratory sense, loss of deep pain and temperature sensation, acute episodic gastrointestinal pain, Charcot joints, and general paresis. Gummatous disease may also present with destructive inflammation and space-occupying lesions. It is caused by granulomatous destruction of visceral organs. They most often involve the frontal and parietal lobes of the brain.