Global Update Indian Pediatrics 2005; 42:301 |
News in Brief |
Post exposure prophylaxis: The new CDC guidelines after exposure to HIV strongly recommend ART. The drugs must be begun within 72 hours of exposure whether it is needle stick or sexual contact. They are to be continued for 28 days. The reduction in transmission is upto the tune of 81%. Combinations recommended are efavirenz with lamivudine or emtricitabine and zidovudine or tenofovir disoproxil, or a protease inhibitor regimen of lopinavir and ritonavir (co-formulated as Kaletra) with lamivudine or emtricitabine and zidovudine. The study has also noted 2 cases of high risk exposure: one with HIV contaminated blood transfusion and on insemination by HIV positive man, in both of which post exposure prophylaxis prevented transmission. It is unclear whether drugs after 3 days of exposure will be ineffective. When HIV status of exposure object is unknown, risk benefit analysis of therapy is to be gauged (MMWR Morbidity and Mortality Weekly Report (Recommendations and Reports) 2005; 54(RR02):1-20). The guidelines are available at www.cdc.gov/mmwr/mmwr_rr.html). Picking up the pieces: So far chromosomal defects like Downs syndrome in the fetus could be picked up non-invasively by testing the mothers blood for fetal genetic material. Now Li et al have reported picking up single gene defect of beta thalassemia in maternal blood taken at 12 weeks gestation with an accuracy of 93.8%. They look for the paternal gene mutation in maternal blood which can happen only by contamination of fetal blood in mothers blood. In the rare event that the paternal and maternal mutation is the same the accuracy would be much lesser. The great advantage of these techniques is that risk of abortion during chorion villous sampling or amniocentesis will be overcome. Work is on to pick up mutations of Tay Sachs and cystic fibrosis using similar techniques (www.nature.com 15 February 2005). Gouri Rao Passi,
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