Cause: Herpes simplextypes I and II
Occurs in babies under age 3 mo born of mothers with active disease (Nejm 1991;324:450) or to asymptomatic but viral shedding mothers (56/15 000) (Nejm 1991;324:1247); immunosuppressed; atopics (eczema)
Asx shedding when no lesions in 10-20% w type I or II genital herpes in 1st year after primary infection (Ann IM 1992;116:433)
Sx + Si:
Encephalopathy: olfactory sensations, focal seizures and si's, low-grade fever, often no skin lesions at all
Disseminated type has classic herpes vesicular rash all over body
Systemic type has fever, malaise, etc
Encephalopathy: rapid course early rx helps, otherwise 70% mortality; in neonatal type still 60% even w acyclovir
Myelitis, hepatitis, pneumonitis, meningitis (Nejm 1982;307:1060); encephalitis may look like temporal lobe mass lesion; r/o similar LACROSSE VIRAL ENCEPHALITIS(Nejm 2001;344:801), for which no approved rx available, mostly in children, 15% have permanent residual defects.
Lab:
Bact:Culture eye, blood, pharynx
CSF: Tzanck prep has a 50% false-negative rate
Path:Brain bx is abnormal
Serol:Diagnostic in 57% (K. Holmes—Ann IM 1983;98:958, 977); most helpful in primary infections, not recurrences
Rx:
Prevent by keeping people with cold sores away from newborns and the immunosuppressed; good handwashing technique; in pregnancy culture weekly, c-section only if clinical lesions when goes into labor because risk of infection in child is <8% if recurrent disease, ~50% if primary (Nejm 1986;315:796; 1986;316:240), but <10% of mothers who cultured herpes at delivery have a h/o herpes lesion (Nejm 1988;318:887). In sexually active pts, about 10%/yr transmit to their partners even when being careful (Ann IM 1992;116:197). Vaccine eventually?
of disease: