Serological tests were performed in the cerebrospinal fluid (CSF) of 13 children with active
congenital syphilis (presence of specific
IgM FTA-ABS
antibodies) and of seven seropositive children with no active
syphilis (FTA-ABS
IgM-negative) born to syphilitic treated mothers in Libreville, Gabon.
Antibodies against treponema were measured by the
Venereal Disease Research Laboratory test (VDRL), the Treponema pallidum haemagglutination assay (TPHA) and the fluorescent treponema antibody absorption tests (FTA-ABS
IgG and
IgM). Of the 13 children with active
syphilis, seven had a positive FTA-ABS
IgG in the CSF. The result of this test was not correlated with the severity of clinical features, CSF
protein levels or number of CSF white blood cells. The CSF-TPHA test was positive in four out of 12 children, and the CSF-VDRL test was negative in all the children with active
congenital syphilis. One of the seven newborns with mother-transmitted
antibodies had a positive FTA-ABS and TPHA in the CSF. These data show that the VDRL is not sensitive enough to diagnose congenital
neurosyphilis, and that FTA-ABS or, at least, TPHA are convenient, sometimes with false-positive results, when a sophisticated method of detecting specific
IgM in CSF is not available.