Abstract
RATIONALE: Neurosyphilis is a relatively common condition that can have stroke-like episodes and is usually seen as an ischemic lesion on magnetic resource imaging (MRI). However, we found a case of diffusion-weighted imaging (DWI)-negative neurosyphilis with stroke-like episodes. PATIENT CONCERNS: After hospitalization, MRI of the head was perfected and no new cerebral infarct lesions were seen, and DWI was negative. However, the patient's left limb weakness was significantly aggravated, and serological examination suggested a positive syphilis test. DIAGNOSES: The patient had a sudden onset of weakness in the left limb. Computed tomography (CT) and MRI brain scans were performed. A CT scan of the head showed no significant abnormalities. MRI of the head showed multiple flaky abnormal signal shadows in the brain, but they were not imaging manifestations of cerebral infarction. Positive serum syphilis spirochete-specific antibodies and rapid plasma reaction test. The same results were subsequently obtained in cerebrospinal fluid tests. Ultimately, the diagnosis of neurosyphilis was established. INTERVENTION: The patient was treated with oral antiplatelet aggregating drugs and penicillin G intravenously. OUTCOME: The patient had progressive exacerbation of limb weakness and grade 1 muscle strength prior to penicillin therapy. After being treated with penicillin, the patient's muscle strength gradually improved. After 10 days of penicillin treatment, the muscle strength was completely normalized. Follow-up after 6 months suggested good recovery. LESSONS: Neurosyphilis can present as a stroke-like episode. However, in this case, the patient presented with a progressive stroke, but the head MRI showed diffuse lesions. This suggests that we have more head imaging changes in patients with neurosyphilis and are wary of misdiagnosis in the clinical setting.