True regarding congenital rubella (CRS) syndrome are all except:
Ans: (c) Cataract in CRS is always bilateralRef: Manual of Neonatal Care, John P. Cloherty, 7th edition, Page 619CONGENITAL RUBELLA SYNDROME (CRS)RNA virus (the toga virus family)Maternal Infection (in gestation)Rate of fetal infectionOccurrence of fetal anomaliesFirst 12 weeks of gestation81%100% of the infected fetuses had cardiac defects and deafnessIn 13 to 16 weeks54%Deafness was found in one-third of fetusesIn 31 to 36 weeks60%No abnormalities were found when fetal infection occurred beyond the 20th week of gestationBeyond 36 weeks100%Clinical Features:Cataracts (can be both unilateral or bilateral), sensory neural hearing loss (single most common finding among the CRS infants), and congenital heart disease (patent ductus arteriosus and pulmonary artery stenosis).Common early features - IUGR, retinopathy (salt and pepper retinopathy), microphthalmia, meningo encephalitis, hypotonia, electroencephalographic abnormalities, dermatoglyphic abnormalities, hepatosplenomegaly, thrombocytopenic purpura, radiographic bone , and diabetes mellitus.Rare complications - myocarditis, glaucoma, microcephaly, chronic progressive panencephalitis, hepatitis, anemia, hypogammaglobulinemia, thymic hypoplasia, thyroid abnormalities, cryptorchidism and polycystic kidney disease.Antenatal Diagnosis:1. Determination of specific IgM in fetal blood obtained by PUBS.2. Direct detection of rubella antigen and RNA in a chorionic villus biopsy specimen.Postnatal Diagnosis: The diagnosis of congenital infection is made by one of the following:i. Isolation of rubella virus (oropharynx, urine).ii. Detection of rubella-specific IgM in cord or neonatal blood.iii. Persistent rubella-specific titers over time (i.e., no decline in titer as expected for transplacentally derived maternal IgG).If, in addition, there are congenital defects, the diagnosis of CRS is made.Treatment:No specific therapy for either maternal or congenital rubella infection.Maternal disease is almost always mild and self-limiting.1. Primary maternal infection occurs during the first 5 months of pregnancy-termination options should be discussed with the mother.2. Infection is known to have occurred beyond the 20th week of gestation, its unlikely to develop anomaliesIndividuals with postnatal infection typically shed virus for 1 week before and 1 week after the onset of rash.Infants with congenital infection may shed virus for many months, and contact should be avoided during the first year.Conception also should be avoided for 3 months following immunization.Immunization during pregnancy is not recommended because of the theoretical risk to the fetus. Inadvertent immunizations during pregnancy have occurred - reassurance of little risk to the fetus can be given.Maternal Infection:Symptoms - begin 2 to 3 weeks after exposure and include malaise, low-grade fever, headache, mild coryza, posterior cervical lymphadenopathy, arthralgias and conjunctivitis.Occurring 1 to 5 days before the onset of rash (salmon-pink macular or maculopapular exanthem that begins on the face and behind the ears and spreads downward over 1 to 2 days and disappears in 5 to 7 days from onset).Confirmation - demonstrating a fourfold or higher rise in serum IgG titers when measured at the time of symptoms and approximately 2 weeks later.If a woman exposed to rubella is known to be seropositive, she is immune, and the fetus is considered not to be at risk for infection.If the exposed woman is known to be seronegative, a serum sample should be obtained 3 to 4 weeks after exposure for determination of titer.A negative titer indicates that no infection has occurred, whereas a positive titer indicates infection.
Infants of congenital rubella syndrome can shed virus in respiratory secretions upto 1 year of age
Risk of developing diabetes mellitus is considerably higher in congenital rubella syndrome
Cataract in CRS is always bilateral
Risk of congenital defects is high when fetus is infected during the first trimester Explanation:
Infection