Table 2.
Demographic and (para)clinical features.
| Case 1 | Case 2 | |
|---|---|---|
| Age (y), sex | 43, male | 44, male |
| Initial symptoms | Numbness in the genital area and lower limbs | Vision loss and pain in the right eye |
| Neurological diagnosis | Cervical myelitis | Optic neuritis |
| Syphilis serology | TPPA+ (1:20,480), VDRL+ (1:16) | TPPA+ (1:1,280), VDRL− |
| Serum MOG-IgG (months after disease onset) | Month 2: geometric MFI ratio of 14 Month 5: geometric MFI ratio of 22 Month 7: geometric MFI ratio of 17 Month 9: geometric MFI ratio of 22 |
Month 0: geometric MFI ratio of 20 Month 5: geometric MFI ratio of 10 Month 8: geometric MFI ratio of 9 Month 9: geometric MFI ratio of 11 |
| Serum NfL (months after disease onset) | Month 2: 5.4 pg/ml (15 percentile) Month 5: 4.0 pg/ml (2.3 percentile) Month 7: 5.2 pg/ml (13 percentile) Month 9: 5.1 pg/ml (12 percentile) |
Month 0: 10.7 pg/ml (88 percentile) Month 5: 8.8 pg/ml (71 percentile) Month 8: 10.2 pg/ml (84 percentile) Month 9: 14.9 pg/ml (97 percentile) |
| Lumbar puncture | 2 leukocytes, protein 440mg, OCB negative, TPPA positive (1:16), VDRL negative | 2 leukocytes, protein 340 mg, OCB negative, TPPA positive (1:2), VDRL negative |
| Anti-AQP4 | Negative | Negative |
| Neurological treatment | IVIG 150 g over 5 days | Methylprednisolone 3 g over 3 days |
| Syphilis treatment | Penicillin 20 million U per day over 14 days | Benzathine penicillin 2.4 million U per week over 3 weeks |
| Comorbidities | HIV CDC A2 (bictegravir, emtricitabine, tenofovir), latent tuberculosis (untreated) | Hepatitis B (tenofovir) |
| Follow-up (8 months) | Asymptomatic new FLAIR lesions in the pons and medulla oblongata and increase in MOG-IgG serum level | Decrease in pRNFL thickness (as expected after optic neuritis) and persistent MOG-IgG seropositivity |
For serum MOG-IgG levels, values below 2.4 are considered negative, values between 2.4 and 3 positive, and values above 3 clear-positive.
TPPA, Treponema pallidum particle agglutination; VDRL, venereal disease research laboratory; OCB, oligoclonal band; IVIG, intravenous immunoglobulin; HIV, human immunodeficiency virus; CDC, Centers for Disease Control and Prevention; FLAIR, fluid-attenuated inversion recovery; MOG, myelin oligodendrocyte glycoprotein; MFI, mean fluorescence intensity; NfL, neurofilament light chain.