Adverse reactions to oxacillin in hospitalized children: a prospective study Reações adversas à oxacilina em crianças hospitalizadas: um estudo prospectivo

OBJECTIVES: follow-up of children exposed to oxacillin during hospitalization focusing on adverse reactions. METHODS: patients were selected from the pediatric wards of two hospitals in Fortaleza (Hospital Universitário Walter Cantídio-HUWC and Hospital Infantil Albert Sabin-HIAS) from the first oxacillin prescription with a prospective cohort study between October, 2000 and July, 2001 (HUWC) and July/2001 and March, 2002 (HIAS). Patients' follow-up was performed by daily visits to the wards and medical charts and prescription analysis. Suspected oxacillininduced adverse reactions (OxAR cases) were notified and classified according to causality and severity. Related statistic tests were completed. RESULTS: of the 130 patients exposed to oxacillin, 27 had OxAR (20.8%). Fever was the most frequent reaction (50%) followed by rash (35.7%). The majority of reactions were considered Probable, for oxacillin was the only medication involved and 92.6% of the cases had Moderate severity with the need of therapeutic interventions caused by OxAR. A significant relation between oxacillin exposure time and OxAR was determined as well as hospitalization time and the appearance of adverse reactions. Exposure time over 14 days to oxacillin was established as a risk factor for OxAR (relative risk = 5.49). CONCLUSIONS: careful administration of oxacillin in children is recommended with established treatment duration. Empiric and prolonged use must be avoided.<br>OBJETIVOS: acompanhar crianças expostas à oxacilina durante hospitalização, com foco na incidência de reações adversas. MÉTODOS: os pacientes foram selecionados em enfermarias pediátricas de dois hospitais de Fortaleza (Hospital Universitário Walter Cantídio-HUWC e Hospital Infantil Albert Sabin-HIAS), desde a primeira prescrição de oxacilina, sendo feita coorte prospectiva entre outubro, 2000 e julho, 2001 (HUWC), e entre julho,2001 e março,2002 (HIAS). O seguimento de pacientes deu-se através de visitas diárias às enfermarias e análise de prontuários e prescrições. Os casos de RAOx foram notificados e classificados quanto à causalidade e gravidade, sendo realizados testes estatísticos pertinentes. RESULTADOS: dos 130 pacientes expostos à oxacilina, 27 apresentaram RAOx (20,8%), sendo febre a reação mais freqüente (50%), seguida do rash cutâneo (35,7%). A maioria das reações foi considerada Provável, pois a oxacilina foi o único medicamento envolvido e 92,6% dos casos tiveram gravidade Moderada, sendo necessárias intervenções terapêuticas devido à RAOx. Uma associação significante entre tempo de exposição à oxacilina e aparecimento de RAOx, assim como entre tempo de internamento e ocorrência de reação foi observada. Um tempo de exposição maior que 14 dias apresentou-se como fator de risco para ocorrência de RAOx (risco relativo = 5,49). CONCLUSÕES: recomenda-se administração cautelosa de oxacilina em crianças, com duração do tratamento estabelecida, evitando-se tratamento empírico e uso prolongado

Performance of the ATLAS track reconstruction algorithms in dense environments in LHC Run 2

With the increase in energy of the Large Hadron Collider to a centre-of-mass energy of 13 TeV for Run 2, events with dense environments, such as in the cores of highenergy jets, became a focus for new physics searches as well as measurements of the Standard Model. These environments are characterized by charged-particle separations of the order of the tracking detectors sensor granularity. Basic track quantities are compared between 3.2 fb(-1) of data collected by the ATLAS experiment and simulation of protonproton collisions producing high-transverse-momentum jets at a centre-of-mass energy of 13 TeV. The impact of chargedparticle separations and multiplicities on the track reconstruction performance is discussed. The track reconstruction efficiency in the cores of jets with transverse momenta between 200 and 1600 GeV is quantified using a novel, datadriven, method. The method uses the energy loss, dE/ dx, to identify pixel clusters originating from two charged particles. Of the charged particles creating these clusters, themeasured fraction that fail to be reconstructed is 0.061 +/- 0.006 (stat.) +/- 0.014 (syst.) and 0.093 +/- 0.017 (stat.) +/- 0.021 (syst.) for jet transverse momenta of 200-400GeV and 1400-1600GeV, respectively