[Clinical and epidemiological survey of RSV infection in infants]. / Estudio clínico-epidemiológico de la infección por virus respiratorio sincitial en el lactante.

OBJECTIVE: A prospective study was performed to assess the clinical and epidemiological characteristics of RSV infections in hospitalized infants. PATIENTS AND METHODS: Between October 1988 and September 1991, we studied 322 cases of RSV respiratory infections diagnosed by EIA of nasopharyngeal lavage and/or serology by complement fixation. Clinical, analytical and radiological data were reviewed. RESULTS: Time-analysis showed higher incidences of RSV infections in December, January, November and February, with an increase in hospital admissions due to respiratory problems before the peak in RSV infections. The mean age of the population was 6.84 +/- 7.07 months. The mean weight was 7.4 +/- 2.68 kg and the sex distribution was 61.2% males and 38.8% females. Blood count was not useful in the differential diagnosis between bronchiolitis/bronchitis and pneumonias, but the erythrocyte sedimentation rate was higher in the last group (25.2 +/- 20.1 versus 38.2 +/- 29.5, t = 2.52, p < 0.05). Clinical status, with a mean value of 6.09 +/- 2.31 as assessed by the modified Downes's Score, showed a significant relationship with the time of hospitalization (mean: 8.77 days; r = 0.2108, p < 0.01), but not with gas exchange, weight or age. Chest X-rays showed air trapping in 48% of the cases, but the incidence of condensation was lower than in other series (16%), probably because we do not believe that any infiltration of the lungs on chest roentgenograms places the patients in the pneumonia category. CONCLUSIONS: We found a high frequency of RSV infection among hospitalized infants and there was seasonal variation with a higher incidence during the winter months.

[Fatty acid concentration analysis in colostrum and transitional milk]. / Análisis de la concentración de ácidos grasos en calostro y leche de transición.

OBJECTIVES: We have studied the quantitative differences in the percent fatty acid composition of human milk throughout its maturational process. MATERIAL AND METHODS: We analyzed milk, obtained by an electrical milk extractor (EGNELL LACT-E AMEDA), from 24 women at 3 days (colostrum) and 7 (transitional milk) after delivery. A Varian 3300 chromatograph was used for fatty acid evaluation. At 48 hours after delivery, the lipid status of the maternal blood was also evaluated. RESULTS: The mean age of the mothers was 27.4 +/- 3.7 years, with 54% primiparous and the mean weight of the newborns was 3117.5 +/- 678.6 g. Comparing colostrum with transitional milk showed a statistically significant difference between saturated fatty acids (C8, C13, and C15) and polyunsaturated fats (C18:3 and C20:4). The concentration of C13, C15, C17, C18, C16:1 and C18:1 obtained in colostrum correlated with those in transitional milk. Serum maternal lipid concentrations of cholesterol and LDL influenced milk levels of C18:2, C18:3 and C20:4. On the contrary, we could not demonstrate a similar influence on triglycerides, apoprotein A or B.

[Hypercapnia induced reversible opening of the blood-brain barrier in experimental hyperbilirubinemia]. / Apertura reversible de la barrera hematoencefálica inducida por hipercapnia en hiperbilirrubinemia experimental.

OBJECTIVE: The incidence of bilirubin encephalopathy in extremely ill neonates with low serum bilirubin is stimulating interest in factors that can modify the blood-brain barrier permeability and allow the passage of bilirubin-albumin macrocomplexes, which may be produced by hypercapnia. MATERIALS AND METHODS: Without modifying the normal bilirubin-albumin affinity, we increased cerebral flow by two levels of hypercapnia (PCO2 67.1 and 101.9 mmHg), acquired by inhalation of CO2 enriched air (5 and 15%) and a decrease in pH (7.00 and 6.93). RESULTS: We demonstrate an increment in cerebral bilirubin deposition (control 2.43 +/- 0.54 mg/g versus 3.29 +/- 0.43 and 3.28 +/- 1.07, F = 4.80, p < 0.05) and I125 albumin (control 26.1 +/- 95.8 micrograms/g versus 364.4 +/- 156.1 and 430.8 +/- 122.4, F03.34, p < 0.05).