Saturday, October 25, 2014

TORCHES

TORCHES
Key Facts
• Congenital or delayed reactivation of ocular disease, maternally transmitted,
resulting in direct infection or teratogenic effect
• TORCHES: toxoplasmosis, rubella, cytomegalic inclusion disease, herpesviruses
(including Epstein–Bar), and syphilis
• Toxoplasmosis:
• obligate intracellular organism Toxoplasma gondii • cats are defi nitive host—
oocysts reside in intestine then are secreted fecally and ingested by humans
• oocysts have predilection for retina and can remain dormant indefi nitely or
rupture • acquired congenitally via transplacental transmission or in childhood
• Rubella (German measles):
• transplacental transmission of rubella virus • eye (cataracts, pigmentary
retinopathy), ear (deafness), and cardiac abnormalities in association with
microcephaly
• Cytomegalovirus:
• transplacential transmission, contact via infected birth canal, or infected breast
milk • herpesvirus family • acquired infections occur in the
immunocompromised • deafness, microcephaly, periventricular calcifi cations,
hematologic and hepatic abnormalities
• Herpes simplex virus (HSV):
• congenital infection occurs during passage through infected birth canal
• acquired infections (HSV type 1 affects skin, eyes, and mouth; HSV type 2 is
a venereal infection acquired via genital contact) • most neonatal cases are
disseminated and involve the central nervous system, lungs, liver, and adrenal
glands • minority of cases cause skin lesions, mouth sores, and
keratoconjunctivitis
• Syphilis:
• spirochete Treponema pallidum • higher rate of transmission in late untreated
maternal infection • prematurity in association with hepatosplenopmegaly,
pneumonia, jaundice, anemia, and lymphadenopathy • periostosis or
metaphysicial abnormalities on x-ray • Hutchinson triad (wide peg-shaped teeth,
eighth nerve deafness, interstitial keratitis)
Clinical Findings
• Toxoplasmosis:
• retinitis with possible choroiditis or anterior uveitis • reactivation may occur
adjacent to an old scar (satellite lesion) • intracranial calcifi cations,
hepatosplenomegaly, microcephaly, and developmental delay
• Rubella:
• nuclear (morgagnian) cataract • microphthalmos • salt and pepper or pseudo
retinitis pigmentosa retinopathy
• Cytomegalovirus:
• microphthalmia, cataracts, uveitis, and retinochoroiditis • diffuse retinal
necrosis with whitening, hemorrhage, and venous sheathing
• Herpes simplex:
• conjunctivitis, keratitis (epithelial or stromal), cataracts, and retinochoroiditis
• Syphilis:
• salt and pepper or pseudo retinitis pigmentosa retinopathy • anterior uveitis or
glaucoma • bilateral interstitial keratitis
Ancillary Testing
• Toxoplasmosis:
• ELISA (enzyme-linked immunoassay) • because IgM does not cross the
placenta, positivity in the infant is evidence for congenital infection
• Rubella:
• serologic testing • isolation of virus from lens material or pharyngeal swabs
• Cytomegalovirus:
• serologic testing • isolation of virus from secretions
• Herpes simplex:
• viral cultures • PCR
• Syphilis:
• VDRL • Fluorescent treponemal antibody absorption or microhemagglutination
assay for T. pallidum antibodies • Long bone x-rays
Differential Diagnosis
• Toxoplasmosis, rubella, cytomegalic inclusion disease, herpesviruses (including
Epstein–Bar), and syphilis (TORCHES)
• Other intrauterine infections
Treatment
• Toxoplasmosis:
• treated primarily if vision-threatening, because active lesions become quiescent
after 1–2 months • systemic corticosteroids in association with pyrimethamine
and sulfadiazine plus folinic acid, or clindamycin, or
trimethoprim–sulfamethoxazole
• Rubella:
• cataract extraction—beware of excess postoperative infl ammation
• Cytomegalovirus:
• intravenous and intravitreal ganciclovir • oral valacyclovir in non–visionthreatening
cases
• Herpes simplex:
• oral acyclovir • topical (trifl uridine 1% one drop nine times per day, vidarabine
3% ointment fi ve times per day; deep stromal or disciform may require topical
corticosteroids) • intravenous antivirals in disseminated disease
• Syphilis:
• intravenous aqueous penicillin G
Prognosis
• Toxoplasmosis:
• if lesion involves macula or optic nerve, vision can be permanently affected
• Rubella:
• depends on extent of retinopathy, density of cataract, and degree of
microcephaly
• Cytomegalovirus:
• depends on extent of retinopathy and whether macula or optic nerve involved
• Herpes simplex:
• depends on extent of disseminated disease and location of corneal infection
• Syphilis:
• depends on extent of congenital abnormalities versus active treatable disease

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