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. 1999 Mar;4(2):109–112. doi: 10.1093/pch/4.2.109

TABLE 3:

Recommended microbiological testing for suspected congenital infections

Specimen Tests Interpretation
Urine Viral culture or detection* (CMV, HSV, rubella) Urine for CMV must be obtained at younger than age two to three weeks.
If positive, test is diagnostic for that infection.
Throat swab Viral detection* (CMV, HSV, rubella, enteroviruses) If positive, test is diagnostic for that infection.
Blood Viral detection* (CMV, parvovirus B19) If positive, test is diagnostic for that infection.
Neonatal serum (single specimen) Rubella-specific IgM If positive, test is diagnostic, although determination of status at 10 to 12 months of age is confirmatory.
Sequential neonatal, infant sera over six to 12 months IgG antibody for etiological agents of concern Passive maternal antibody in uninfected infant disappears at

  • four to nine months of age for CMV (unless peri- or postnatally transmitted);

  • eight months for Toxoplasma gondii; and

  • six months VDRL/rapid plasma reagent and 12 to 15 months treponemal test (eg, fluorescent treponemal antibody absorbed with nonpallidum treponemes).
Positive specific antibody at eight to 12 months suggests congenital toxoplasmosis parvovirus B19, rubella or varicella zoster virus infection.
Single maternal serum at delivery Toxo-specific IgM (or toxoplasmosis-specific) If IgM-specific antibody is positive, reference laboratory testing of maternal and infant sera is recommended.
Serology of both mother and infant IgG antibody for etiological agents of concern Negative maternal serology rules out source of infection.
Serial infant serology identifies passive maternal antibody (titres fall) and active infection (titres remain the same or rise over months).
Cerebrospinal fluid culture, detection Detection* CMV, enteroviruses, HSV, toxoplasmosis (reference laboratory), parvovirus B19
Rubella-specific IgM antibody VDRL		 If positive, usually diagnostic for that infection.
Skin lesions culture, detection If vesiculated at birth: detection* of herpes, enteroviruses, varicella zoster virus and dark-field for Treponema pallidum (syphilis) If positive, test is diagnostic for that infection.
Nasopharyngeal secretions Dark-field for T pallidum (syphilis) If positive, test is diagnostic for that infection.
Stool culture Enteroviruses If positive, test may be diagnostic for that infection.
Placenta Pathology Variable
*

Detection refers to culture or polymerase chain reaction testing. CMV Cytomegalovirus; HSV Herpes simplex virus; Ig Immunoglobulin; VDRL Venereal Disease Research Laboratory test