Samuel P. Gotoff

Most cases of neonatal group B streptococcal disease with early onset have an intrapartum pathogenesis. Attack rates are increased substantially in infants born to mothers with prenatal group B streptococcal colonization and various perinatal risk factors (premature labor, prolonged membrane rupture, or intrapartum fever). In a randomized controlled trial, we studied the effect of selective intrapartum prophylaxis with ampicillin in 160 such high-risk women. In infants born to mothers who received intravenous ampicillin during labor, as compared with controls who received no treatment, neonatal colonization with group B streptococci was present in 8 of 85 (9 percent) versus 40 of 79 (51 percent; P less than 0.001), colonization at multiple (greater than or equal to 3) sites was observed in 3 of 85 (4 percent) versus 24 of 79 (30 percent; P less than 0.001), and bacteremia occurred in none of 85 versus 5 of 79 (6 percent; P = 0.024). The side effects of ampicillin were limited to a single episode of urticaria in a mother who had no history of penicillin allergy. We conclude that intrapartum ampicillin prophylaxis in women with positive prenatal cultures for group B streptococci who have certain perinatal risk factors can prevent early-onset neonatal group B streptococcal disease.

Between 1973 and 1981, 61 cases of neonatal group B streptococcal early-onset disease occurred among 32,384 infants born at Michael Reese Hospital and Medical Center, Chicago. Forty-one (67%) of the 61 affected infants were bacteremic at birth, implying intrapartum acquisition of infection. No significant deviations from the overall attack rate of 1.9 per 1,000 live births were associated with maternal demographic factors, but increased attack rates were associated with birth weights of less than or equal to 2.5 kg (7.9 per 1,000), rupture of amniotic membranes greater than 18 hr before birth (7.6 per 1,000), and intrapartum fever (6.5 per 1,000). Forty-five (74%) of the 61 affected infants and 15 (94%) of the 16 with fatal outcome had one or more of these three perinatal risk factors. Based on an intrapartum vaginal carriage rate of 16.7% among parturients with perinatal risk factors, an attack rate of 45.5 per 1,000 was estimated for infants born to colonized "high-risk" parturients, a subgroup comprising approximately 3% of our obstetric population. These findings provide a compelling epidemiologic rationale for trials of selective intrapartum chemoprophylaxis of neonatal group B streptococcal early-onset disease.

To determine the value of prenatal cultures in defining maternal colonization status at delivery, 5,586 pregnant women were screened at prenatal visits for vaginal and rectal carriage of group B streptococci (GBS). GBS were isolated from 1,272 (22.8%). At delivery, semiquantitative cultures were obtained from 393 prenatal carriers, of whom 264 (67.2%) retained carriage at delivery. Seventeen (8.5%) of 200 women with negative prenatal cultures acquired carriage. The predictive value of a positive prenatal culture was highest (72.5%) in women with prenatal vaginal and rectal colonization and lowest (59.7%) in women with only rectal colonization. The predictive value varied inversely with the interval between prenatal sampling and delivery. In mothers with prenatal carriage, density of colonization at parturition was not predicted by the sites of prenatal colonization. Density of colonization, however, strongly influenced rates of vertical transmission to neonates and rates of heavy infant colonization. Ten infants born to prenatally cultured mothers developed group B streptococcal early-onset disease; the mothers of eight (80%) of the 10 had prenatal colonization with the homologous GBS serotype.

ATAXIA telangiectasia is an inherited disorder characterized by progressive cerebellar ataxia and oculocutaneous telangiectasia.^1-3Generally these patients have recurrent sinopulmonary infections, and defects in cellular immunity and in the immunoglobulin system have been recently documented.^4-9An unusual propensity for the development of neoplasia has become apparent.^2-4,10-14In previous cases the neoplasms have been discovered close to or at the time of death, obviating therapy. Since this is apparently the first instance in which a patient with ataxia telangiectasia has been treated for a lymphosarcoma, we wish to call attention to the severe untoward effect of a partial therapeutic dose of x-irradiation. In addition, we found typical lesions of tuberous sclerosis in the brain and unusual hypertrophic cells in the renal tubules. These findings, associated with the development of a lymphosarcoma, suggest a generalized disturbance in the metabolic control of many cell types. <h3>Report of a Case</h3> A

Americanae nace como un proyecto conjunto que surge dentro de la Red Europea de Información y Documentación sobre América Latina (REDIAL), y que ha afrontado la Biblioteca de la Agencia Española de Cooperación Internacional para el Desarrollo (AECID). Esta nueva biblioteca virtual hace más accesibles los libros digitales de tema americanista a los investigadores y usuarios interesados de cualquier parte del mundo.