Clinical History
32-year-old gentleman with progressive cognitive decline and memory impairment for 2 years.
Imaging Findings
FIGURE 1 a to d: Pre-contrast T1, T2 and FLAIR along with post-contrast T1 images. There is an asymmetrically dilated ventricular system with prominent extra-axial CSF spaces. No periventricular CSF seepage. In addition the temporal lobes are dilated and the hippocampus is flattened more on the right side. Normal corpus callosum, brain stem and visualised cervical cord.
These findings are suggestive of generalized brain and hippocampal atrophy unusual for the patient’s age.
FIGURE 2 a to d: Pre and post-contrast FLAIR images showing prominent leptomeningeal enhancement (white arrows) along with sulcal and gyral hyperintensities.
Discussion
Syphilis is an infectious disease caused by bacteria Treponema Pallidum, a thin tightly coiled spirochete. Human beings are the only host of this spirochete which is transmitted by intimate contact of lesions of skin or mucous membrane (genitalia, mouth and rectum) from an infected person. Neurosyphilis results from an invasion of the brain, meninges and spinal cord by the bacteria. Syphilis occurs worldwide, and its incidence is increasing recently in homosexual men and HIV patients. [1]
The symptoms of neurosyphilis include insidious and subtle personality changes, mood disturbance, cognitive decline that progresses after many months or less commonly to dementia. Sometimes seizure or stroke with acute focal neurological deficit is the initial manifestation. The patient can also present with psychosis, delirium, delusion, manic–depressive symptoms. [2]
There is no single reliable examination for diagnosis of neurosyphilis. Diagnosis depends on clinical features, serologic test and imaging findings. Non-specific serologic tests include VDRL and RPR while FTA-ABS, TPHA and MHA-TP are the specific tests. Diagnosis of neurosyphilis is based on CSF WBC count of 20 cell/ul or greater, and reactive CSF VDRL, and of positive intrathecal T.pallidum antibody index. The most prominent diagnostic phenomenon associated with neurosyphilis are atrophy, white matter lesions, cerebral infarction, meningeal enhancement and oedema. [3]
This patients had a history of cognitive impairment for 2 years. No signs of raised ICP clinically as well as on fundoscopy. MRI images show ventricular dilatation more towards the right side along with widened cortical sulci without periventricular CSF seepage. These findings are suggestive of generalized brain and hippocampal atrophy unusual for the patient’s age. Final diagnosis of neurosyphilis was made on CSF DR and serum VDRL/RPR ratio. CSF shows raised protein and cell counts and serum VDRL/RPR ratio was 1:1024.
This patient was given aqueous penicillin G 18-24 million units per day per centre for disease control (CDC) 2015 guidelines. Follow up 5 month after treatment showed reduced CSF cell counts and serum VDRL/RPR ratio of 1:4. Significant clinical improvement was also documented.
Differential Diagnosis List
Temporal lobe atrophy and meningoencephalitis secondary to neurosyphilis
Acute meningoencephalitis
Progressive dementia
Psychosis
Final Diagnosis
Temporal lobe atrophy and meningoencephalitis secondary to neurosyphilis
