Abstract
Dear Editor,
We read with interest the article by Pilozzi-Edmonds 1 about a HIV-positive neurosyphilis patient, and we would like to report our experience on two neurosyphilis immunocompetent cases. In HIV-positive patients, the disease is more commonly seen and follows a more fulminant course than in immunocompetents, in whom it manifests more insidiously and with non-specific symptoms. 2
A 59-year-old heterosexual man presented with a three-month history of vertigo, headache, gait instability and generalised tonic-clonic seizures. Neurological examination revealed diminished bilateral patellar reflex, anisocoria, positive Romberg and Argyll-Robertson sign. A brain magnetic resonance (BMR) revealed T2/FLAIR hyperintensities in the subcortical white matter and cerebellar cortex. Electroencephalogram showed epileptiform discharge over the temporal region. Fundoscopy demonstrated bilateral papillary hyperaemia.
Routine laboratory examinations were normal and HIV test was negative. Serology revealed positivity for Venereal Disease Research Laboratory (VDRL) test and Treponema pallidum haemagglutination assay (TPHA) with titres of 1:64 and 1:1280, respectively. Anti-Treponema pallidum IgG antibodies were found by Treponema pallidum enzyme-linked immunosorbent assay (ELISA); IgM was negative. A cerebrospinal fluid (CSF) analysis revealed 65 white cells/mm 3 , high protein levels (70 mg/dL) and positive VDRL (titre of 1:32) and TPHA (1:128).
Our second patient was a 64-year-old heterosexual man with a six-month history of dizziness, tinnitus and fainting episodes presented with headache, gait instability and leg numbness. Neurological examination revealed diminished bilateral patellar reflexes, positive Romberg sign and leg sensory impairment. BMR revealed T2/FLAIR hyperintensities in the frontal, left parietal lobes and cerebellar cortex, consistent with remote ischaemic injuries. Audiometry, Doppler sonography of supra-aortic vessels and routine laboratory examinations were normal; HIV test was negative.
Serology revealed positivity for VDRL (1:64) and TPHA (1:1640). ELISA anti-Treponema pallidum IgG antibodies were positive and IgM was negative. CSF analysis revealed 75 white cells/mm 3 , high protein levels (80 mg/dL) and positive VDRL (1:16) and TPHA (1:64).
Both these patients were treated for primary syphilis 15 and 25 years before with intramuscular benzathine penicillin G (BPG) 42 million units (MU) in total, achieving a four-fold decrease in VDRL after 12 months.
The patients were monitored with annual dermatological examinations and laboratory testing in which Treponema pallidum IgM antibodies were always negative and VDRL and TPHA titres remained stable or decreased. Furthermore, both patients reported no sexual risk behaviour since the treatment for early syphilis. According to these data, a syphilis reinfection was excluded.
They were diagnosed as meningovascular neurosyphilis and received intravenous penicillin G 4 MU/6 h for 15 days with complete recovery. After one year, they had no clinical signs, and VDRL and TPHA titres showed a four-fold decrease in serum and CSF.
Our experience reveals that BPG may be inadequate in preventing late complications of syphilis. This conclusion is also supported by the literature concerning BPG serological treatment failures and on the remarkable number of patients with late complications despite therapy. Furthermore, confidence in BPG use for syphilis has recently wavered as the result of studies conducted in immunocompetent and HIV-infected patients.3–5
Finally, neurosyphilis may have atypical manifestations that may be misleading. Physicians are encouraged to test for syphilis in patients with neurological symptoms without unambiguous causes and should not settle on the excellent results obtained by BPG in skin manifestations but should re-examine the treatment to prevent late complications. Other treponemicidal antibiotics, such as cephalosporins and tetracyclines (used successfully in the treatment of neuroborreliosis), that can penetrate all tissues more effectively than BPG may be considered at completion of standard BPG therapy.6,7