Isabel Carvalho

Evaluation of the third-order nonlinear optical properties of tellurite glasses by thermally managed eclipse Z-scan

The third-order nonlinearity is measured for TeO2–ZnO–Na2O (TZN) glasses codoped with BaO, Nb2O5, and La2O3. The results for the sign and magnitude of the nonlinearity were obtained using a combination of the eclipse Z-scan with thermal nonlinearity managed Z-scan, whereas the Kerr shutter technique was employed to obtain the electronic time response of the nonlinearity, all performed with 76 MHz repetition rate 150 fs pulses at 800 nm. The results show a fast response (<200 fs) and a nonlinear refractive index varying from 1.5 to 3.5×10−15 cm2/W, depending upon glass composition. At the peak power level employed, nonlinear absorption was negligible. The results obtained are in good agreement with other tellurite compositions reported, confirming the electronic origin of the nonlinearity

The value of family history in the diagnosis of hypersensitivity pneumonitis in children

Hypersensitivity pneumonitis (HP), or extrinsic allergic alveolitis, is an immunologically mediated disease resulting from the inhalation of organic substances that trigger an inflammatory response in the alveolar wall, bronchioles, and interstitium in susceptible individuals. Although HP is predominantly an occupational disease, seen in adulthood, cases in children have been described. The diagnosis of HP requires a high degree of suspicion. The treatment consists in avoiding contact with the antigen, and, in some cases, systemic corticosteroids might be necessary in order to prevent its progression to pulmonary fibrosis. We report the clinical cases of three children with a history of contact with birds and a family history of HP. All three patients presented with cough and dyspnea on exertion. The disease was diagnosed on the basis of the clinical history and ancillary diagnostic test results consistent with the diagnosis, including a predominance of lymphocytes (> 60%, CD8+ T lymphocytes in particular) in bronchoalveolar lavage fluid and a ground-glass pattern seen on HRCT of the chest. Early diagnosis is crucial in order to prevent HP from progressing to pulmonary fibrosis. Hereditary factors seem to influence the onset of the disease.

Tuberculosis disease - statistics of a paediatric department in the 21st century.

INTRODUCTION Tuberculosis is a leading cause of world -wide mortality and morbidity. A reduced rate of tuberculosis in people aged less than 15 years has been seen in Portugal over the last decade of the twentieth century. MATERIAL AND METHODS Retrospective analysis of tuberculosis cases in children admitted to the Centro Hospitalar de Vila Nova de Gaia January 1 2000 to December 31 2007. The individual epidemiological, clinical, radiological, microbiological and treatment information was analysed. RESULTS We found 23 cases of tuberculosis disease (78% pulmonary tuberculosis and 22% extra- -pulmonary tuberculosis). Childrens ages varied from 6 months to 16 years, with the male gender predominant. All patients had previously been vaccinated with BCG and there was a prior contact with TB in 57%. 2007 was the year with the highest number of cases. The Mantoux test was positive in 91% cases and M. tuberculosis isolation was possible in 61%. Gastric fluid analysis allowed isolation in 1/3 of cases and bronchoscopy contributed to M. tuberculosis isolation in 43% cases with negative gastric fluid analysis. Every patient underwent at least 6 months of tuberculostatic treatment, without any documented resistances. CONCLUSION Tuberculosis remains a real problem, with the diagnosis, the search for contacts and adequate treatment (including prophylaxis) the main challenge.

Tuberculosis in undiagnosed children: What are the criteria to start treatment in Portugal?

rldwide, about 9 million individuals per year are newly ected with tuberculosis (TB), 1 million of which are chiln under 15 years of age.1 In Europe between 2000 and 09, only 42.3% of patients with pediatric TB were assessed culture, and only 39.9% of those tested were culture sitive.1 In fact, the confirmation rate among pediatric ses was 19.2% in Europe in 20091 and 27.6% in Portul from 2000 to 2009.2 The variability and low specificity imaging findings were nodules and cavities (96%), adenopathies (41%), pleural effusion (41%) and ‘‘treein-bud’’ appearance (26%). Clinical determinants associated with the decision to start treatment included sustained fever (55%), respiratory symptoms (41%) and failure to thrive (34%). The average time window considered for these symptoms was 36.5 days (range, 7 days to 3 months). Immunological tests considered relevant to the decision to treat included tuberculin tests (41%) and interferon gamma assays (28%). History of exposure to a patient with active disease and the presence of clinical and radiological changes associated with disease progression were considered especially va rad are TB for ag

Antituberculosis Drug-Induced Liver Injury with Autoimmune Features: Facing Diagnostic and Treatment Challenges

The authors present a case report of antituberculosis drug-induced liver injury that offered diagnostic challenges (namely, the possibility of drug-induced autoimmune hepatitis) and treatment difficulties.

Um caso de pneumotórax espontâneo recorrente

Resumo O pneumotorax espontâneo e uma patologia rara na idade pediatrica estando, na maioria dos casos associado a um factor predisponente. Apresenta-se o caso clinico de uma crianca de 9 anos, com antecedentes de prematuridade e ventilacao mecânica no periodo neonatal, internado por pneumotorax espontâneo. Apesar da melhoria clinica e radiologica significativa apos drenagem pleural, verificou-se recorrencia do pneumotorax cerca de tres meses depois, identificando-se uma area de enfisema local e necessitando de tratamento cirurgico. O caso clinico descrito distingue-se pela baixa frequencia desta patologia neste grupo etario e pela eventual relacao com os antecedentes neonatais da crianca. Rev Port Pneumol 2008; XIV (5): 693-697