RESUMO
We sought to determine cytokine response in term and late preterm newborn infants on phototherapy. Twenty newborn infants with gestational age > or = 35 weeks and birth weight > or = 2000 g in the first week of life had serum interleukin (IL)-6, IL-8, IL-10, IL-1beta, and tumor necrosis factor (TNF)-alpha measured immediately prior to and after 24 hours on phototherapy. Exclusion criteria were newborns with severe congenital malformations, congenital infections, birth asphyxia, sepsis, hemolytic anemia that required blood transfusion, maternal-infant Rh incompatibility and those who required exchange transfusion or intravenous immunoglobulin treatment for hyperbilirubinemia. Median IL-6 concentrations significantly decreased after 24 hours on phototherapy (18.3 pg/mL and 7.85 pg/mL, respectively, p = 0.005). IL-6 concentrations decreased in 17 out of the 20 newborns. There were no statistical differences in IL-8, IL-10, IL-1beta, and TNF-alpha concentrations before and after 24 hours on phototherapy. There was a statistically significant correlation between IL-6 decline and irradiance (r = 0.57, p = 0.009). The finding that serum IL-6 decreases in newborn under phototherapy suggests that phototherapy possibly has an anti-inflammatory effect, although the clinical implications of this study deserve further studies.
Assuntos
Citocinas/sangue , Icterícia Neonatal/radioterapia , Fototerapia , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Interleucina-10/sangue , Interleucina-1beta/sangue , Interleucina-6/sangue , Interleucina-8/sangue , Masculino , Estresse Oxidativo/efeitos da radiação , Fator de Necrose Tumoral alfa/sangueRESUMO
The irradiance delivered by a phototherapy unit is an important contributing factor to its efficacy. However, measurement of irradiance during phototherapy requires the use of a photometer which is rarely available in the nurseries of developing countries. We assessed the irradiance of phototherapy units both in the laboratory and in all public hospitals of the City of Rio de Janeiro and found that: a) there is no consensus among companies manufacturing phototherapy units as to the number of fluorescent lights to be used in an equipment since this number varied from 4 to 8, b) over 1/3 of the phototherapy units analysed had 1 or more burnt out lamps, c) the mean irradiance delivered by phototherapy units was 2.36 +/- 0.75 muw/cm2/nm (0.6 to 4.4 muw/cm2/nm) which is considerably lower than the dose currently recommended for clinical efficacy. These results may be relevant to other developing countries where phototherapy meters are seldomly available and irradiance is not routinely measured.