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o A two-dose treatment of the antiretoviral drug nevirapine, a non-nucleoside reverse tanscriptase inhibitor that has a long half-life and readily passes from the mother to the fetus, has been found to cause a significant decrease in vertical transmission of HIV. In this study, 600 pregnant HIV-infected women in Uganda were divided in two equal groups and given either antiretroviral zidovudine (AZT) or nevirapine. Without antiretroviral treatment about 25-35% of infants of HIV-infected mothers are expected to be born infected. In this trial, however, at 14-16 weeks of age, only 13% of the children in the nevirapine group were HIV infected, compared with 25% of those in the zidovudine group, a reduction of 47%. If this treatment, which costs $4 only, is implemented, it could save about 400,000 newborns from HIV infection each year, say the researchers. (Lancet 1999; 354, 24 Jul). o Rotavirus vaccine, which was introduced with much publicity, has now been put on hold. An estimated 1.5 million doses of Rotashield have been given in the USA. As of 7 July 1999, 15 cases of intussusception in children had been reported, of which 13 of the cases (87%) developed symptoms within 1 week of vaccination (Mor Mortal Wkly Rep CDC Surveill Summ 1999; 48: 577-81). These reports, though preliminary, have prompted the US Centers for Disease Control and Prevention in recommending that health-care providers postpone giving the vaccine until November 1999. By that time, the CDC hopes that case-control studies designed to determine whether there is an increased risk of intussusception associated with the vaccine will have been completed (Lancet 1999; 354, 24 Jul). A policy of wait and watch is best before introducing new vaccines! o Intrauterine torsion of the testis was first described in the 19th century, but only 28 cases have been reported. Nevertheless, doctors who examine newborn babies should be aware of the conditions; in a recent series of five cases the diagnosis was delayed for a median of 22 hours (Brit J Urol 1999; 83: 1023). The clinical signs are usually obvious; the affected testis is enlarged, firm, and tender, and the overlying skin is dark red. o Iron-deficiency anemia has long been associated with pica, a phenomenon in which people crave unusual food and nonfood substances such as dirt and clay. Now, a report has linked the deficiency with a craving for tomatoes. Tomatoes are not presently included in the list of foods that are associated with pica. Though this letter describes an isolated case, the author says that it is advisable to check the hemoglobin of patients who report any unusual cravings (N Engl J Med 1999; 341: 60). o Potential for catch-up growth among stunted children is thought to be limited after 2 years of age, particularly when they remain in poor environments. The improvements in height status from age 2 to 12 years in a cohort of more than 2,000 children were studied. It was found that low birth weight, which was associated with more severe stunting in the first 2 years of life, significantly reduced likelihood of catch-up growth in later childhood. In contrast, children with taller mothers, who were first born, longer at birth, less severely stunted in early infancy and those with fewer siblings were more likely to increase height for age between ages 10 to 12 years. These results suggest that there is a large potential for catch-up growth in children into the preadolescent years (J Nutr 1999; 129: 1140). o Evidence in favour of use albuterol (salbutamol) delivered by a metered dose inhaler (MDI) with a spacer as compared to a nebulizer, in treatment of children with mild acute asthma is accumulating. In this randomized double-blind trial set in an emergency department, 90 children between 5 and 17 years of age were treated with a single dose of albuterol, with an MDI with spacer or 0.15 mg/kg with a nebulizer (n = 30). In children with mild acute asthma, treatment with 2 puffs of albuterol by an MDI with spacer was just as clinically beneficial as treatment with higher doses delivered by an MDI or by a nebulizer (J Pediatr 1991; 135: 22). A related editorial comments that, despite the increasing acceptance of "evidence-based" therapeutics, the "tried and true" may persist long after the evidence is overwhelmingly in favor of change. o In this study, the effect on smoking in pregnancy on auditory theshold of infants was studied. Twenty-six newborns were studied with polygraphic recordings for 1 night: 13 were born to mothers who did not smoke, and 13 were born to mothers who smoked. More intense auditory stimuli were needed to induce arousals in newborns and infants of smokers than in infants of nonsmokers. Behavioral awakening occurred significantly less frequently in the newborns of smokers than of nonsmokers. Moreover, the impact of exposure to cigarette smoke was found to occur before birth. The study concluded that newborns and infants born to smoking mothers had higher arousal thresholds to auditory challenges than those born to nonsmoking mothers (J Pediatr 1999; 135:34). o Optimistic feeling during pregnancy is helpful! A study on 120 Hispanic and 110 white pregnant women showed that women who reported feeling positive about themselves, their futures and their ability to control important aspects of their lives were more likely to deliver larger babies at term. In contrast, women reporting high levels of emotional stress were more likely to give birth prematurely or to low birth weight infants. How maternal self-esteem, optimism and mastery affect infant birthweight is unclear, but researchers suggest that women with strong personal resources are more likely to lead healthier lifestyles and refrain from smoking, alcohol and drug use during pregnancy (Health Psychol 1999; 18: 1). o More on Vitamin A! Vitamin A supplementation may be an effective low-cost strategy to lower morbidity due to Plasmodium falciparum in young children. In a randomized trial of vitamin A supplemen-tation in a Plasmodium falciparum-endemic area of Papua New Guinea, there was a 30% decrease in P. falciparum febrile episodes in children taking a vitamin A supplement than in those taking placebo. Children aged 12-36 months benefited the most. Treatment did not, however, affect the proportion of children infected or the proportion with anemia. The mechanism is probably due to the effect of Vitamin A on the immune system, concludes the study (Lancet 1999; 354: 201). In another study, weekly low-dose (10,000 IU) vitamin A supplementation in a region of subclinical deficiency protected underweight children from acute lower respiratory infections (ALRI) and diarrhea, but paradoxically increased ALRI in normal children. (Pediatrics 1999; 104: e1). o The effect of a 3-day course of early dexamethasone therapy on the incidence of chronic lung disease (CLD) was studied on neonates (dexamethasone n = 118, placabo n = 123), who weighed between 500g and 1500 g and had received surfactant. Infants randomized to receive early dexamethasone were given 6 doses of dexamethasone at 12-hour intervals beginning at 24 to 48 hours of life. The study concluded that an early 3-day course of dexamethasone therapy increases survival without CLD, reduces CLD, and reduces late dexamethasone therapy increases survival without CLD, reduces CLD, and reduces late dexamethasone therapy in high-risk, low birth weight infants who receive surfactant therapy for respiratory distress syndrome. However, the authors cautioned that the potential benefits of early dexamethasone therapy at the dosing schedule used in this trial need to be weighed against the risk for early intestinal perforation (Pediatrics 1999; 104: 91). C Vidyashankar, |
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