Which of the following infection, if occurs in the first trimester, leads to maximum incidence of congenital malformations: March 2010

Ans. A: Rubella T = toxoplasmosis: Caused by protozoan - Toxoplasma gondii - Domestic cat is the definitive host with infections : Ingestion of cysts (meats, garden products), Contact with oocysts in feces - Much higher prevalence of infection in European countries - Acute infection usually asymptomatic 1/3 risk of fetal infection with primary maternal infection in pregnancy - Infection rate higher with infection in 3rd trimester - Fetal death higher with infection in 1st trimester - Mostly (70-90%) asymptomatic at bih Classic triad of symptoms: Chorioretinitis Hydrocephalus Intracranial calcifications 0=other (syphilis) - Early congenital (typically 1st 5 weeks): Cutaneous lesions (palms/soles) Jaundice Anemia Snuffles Periostitis and metaphysial dystrophy Funisitis (umbilical cord vasculitis) - Late congenital: Frontal bossing Sho maxilla High palatal arch Hutchinson teeth 8th nerve deafness Saddle nose Perioral fissures R = rubella Sensorineural hearing loss (50-75%) Cataracts and glaucoma (20-50%) malformations (20-50%) Neurologic (10-20%) Others to include growth retardation, bone disease, thrombocytopenia, "blueberry muffin" lesions C = cytomegalovirus (CMV) 90% are asymptomatic at bih Up to 15% develop symptoms later, notably sensorineural hearing loss Symptomatic infection Petechiae, jaundice, chorioretinitis, periventricular calcifications, neurological deficits >80% develop long term complications Hearing loss, vision impairment, developmental delay H=herpes simplex (HSV) Most are asymptomatic at bih - 3 patterns of equal frequency with symptoms between bih and 4 weeks: Skin, eyes, mouth (SEM) CNS disease Disseminated disease (present earliest) Initial manifestations very nonspecific with skin lesions NOT necessarily present