LIDIA YAMAMOTO
Projetos de Pesquisa
Unidades Organizacionais
LIM/48 - Laboratório de Imunologia, Hospital das Clínicas, Faculdade de Medicina
4 resultados
Resultados de Busca
Agora exibindo 1 - 4 de 4
- Myocarditis in children and detection of viruses in myocardial tissue: Implications for immunosuppressive therapy(2011) CAMARGO, Paulo Roberto; OKAY, Thelma Suely; YAMAMOTO, Lidia; NEGRO, Gilda Maria Barbaro Del; LOPES, Antonio AugustoBackground: There is scarce information on the potential benefits of immunosuppression in children with myocarditis and viral genomes in myocardium. We investigated the occurrence of myocarditis in children with a preliminary diagnosis of dilated cardiomyopathy, the frequency of cardiotropic viruses in the myocardium, and the response to immunosuppression. Methods: Thirty patients (nine months to 12 years) with left ventricular ejection fraction of 22.8 +/- 4.1% were subjected to right cardiac catheterization and endomyocardial biopsy. Specimens were analyzed for the presence of inflammatory elements (Dallas criteria) and viral genome (polymerase chain reaction). Patients with active myocarditis received immunosuppressants (azatioprine and prednisone) and were recatheterized nine months later. A historical control group of nine patients with myocarditis who did not receive immunosuppressants was included. Results: Active myocarditis was diagnosed in ten patients (five with viral genomes detected). Immunosuppression resulted in a significant increase in left ventricular ejection fraction from 25.2 +/- 2.8% to 45.7 +/- 8.6% (versus 20.0 +/- 4.0% to 22.0 +/- 9.0% in historical controls, p < 0.01) and cardiac index from 3.28 +/- 0.51 L/min/m(2) to 4.40 +/- 0.49 L/min/m(2) (versus 3.50 +/- 0.40 L/min/m(2) to 3.70 +/- 0.50 L/min/m(2) in controls, p < 0.01), regardless of the presence of viral genomes (p - 0.98 and p - 0.22, respectively for the two variables). No relevant clinical events were observed. Non-inflammatory cardiomyopathy was diagnosed in 20 patients (seven with viral genomes). While on conventional therapy, there were four deaths and three assignments to transplantation, and no improvement of left ventricular ejection fraction in the remaining ones (22.5 +/- 3.6% to 27.5 +/- 10.6%). Conclusion: Children with chronic myocarditis seem to benefit from immunosuppressive therapy, regardless of the presence of viral genome in the myocardium.
- DETECTION OF Bartonella henselae DNA IN CLINICAL SAMPLES INCLUDING PERIPHERAL BLOOD OF IMMUNE COMPETENT AND IMMUNE COMPROMISED PATIENTS BY THREE NESTED AMPLIFICATIONS(2013) KAWASATO, Karina Hatamoto; OLIVEIRA, Lea Campos de; VELHO, Paulo Eduardo Neves Ferreira; YAMAMOTO, Lidia; NEGRO, Gilda Maria Barbaro Del; OKAY, Thelma SuelyBacteria of the genus Bartonella are emerging pathogens detected in lymph node biopsies and aspirates probably caused by increased concentration of bacteria. Twenty-three samples of 18 patients with clinical, laboratory and/or epidemiological data suggesting bartonellosis were subjected to three nested amplifications targeting a fragment of the 60-kDa heat shock protein (HSP), the internal transcribed spacer 16S-23S rRNA (ITS) and the cell division (FtsZ) of Bartonella henselae, in order to improve detection in clinical samples. In the first amplification 01, 04 and 05 samples, were positive by HSP (4.3%), FtsZ (17.4%) and ITS (21.7%), respectively. After the second round six positive samples were identified by nested-HSP (26%), eight by nested-ITS (34.8%) and 18 by nested-FtsZ (78.2%), corresponding to 10 peripheral blood samples, five lymph node biopsies, two skin biopsies and one lymph node aspirate. The nested-FtsZ was more sensitive than nested-HSP and nested-ITS (p < 0.0001), enabling the detection of Bartonella henselae DNA in 15 of 18 patients (83.3%). In this study, three nested-PCR that should be specific for Bartonella henselae amplification were developed, but only the nested-FtsZ did not amplify DNA from Bartonella quintana. We conclude that nested amplifications increased detection of B. henselae DNA, and that the nested-FtsZ was the most sensitive and the only specific to B. henselae in different biological samples. As all samples detected by nested-HSP and nested-ITS, were also by nested-FtsZ, we infer that in our series infections were caused by Bartonella henselae. The high number of positive blood samples draws attention to the use of this biological material in the investigation of bartonellosis, regardless of the immune status of patients. This fact is important in the case of critically ill patients and young children to avoid more invasive procedures such as lymph nodes biopsies and aspirates.
- Assessment and comparison of bacterial load levels determined by quantitative amplifications in blood culture-positive and negative neonatal sepsis(2018) STRANIERI, Ines; KANUNFRE, Kelly Aparecida; RODRIGUES, Jonatas Cristian; YAMAMOTO, Lidia; NADAF, Maria Isabel Valdomir; PALMEIRA, Patricia; OKAY, Thelma SuelyBacterial sepsis remains a major cause of mortality and blood cultures are the gold standard of laboratory diagnosis even though they lack sensitivity in neonates. Culture-negative sepsis, also known as clinical sepsis, has long been considered a diagnosis in neonatal intensive care units because, as well as culture-positive infants, culture-negative neonates have worse prognosis in comparison with non-infected ones. Quantitative amplifications are used to detect bacterial infections in neonates but results are considered only in a qualitative way (positive or negative). The aim of the present study was to determine and compare bacterial load levels in blood culture-positive and culture-negative neonatal sepsis. Seventy neonates with clinical and laboratory evidence of infection admitted at three neonatal intensive care units were classified as blood culture-positive or culture-negative. Blood samples obtained at the same time of blood cultures had bacterial load levels assessed through a 16S rDNA qPCR. Blood cultures were positive in 29 cases (41.4%) and qPCR in 64 (91.4%). In the 29 culture-positive cases, 100% were also positive by qPCR, while in the 41 culture-negative cases, 35 (85.4%) were positive by qPCR. Bacterial load levels were in general < 50 CFU/mL, but were significantly higher in culture-positive cases (Mann-Whitney, p = 0.013). although clinical and laboratory findings were similar, excepting for deaths. In conclusion, the present study has shown that blood culture-negative neonates have lower bacteria load levels in their bloodstream when compared to blood culture-positive infants.
- Usefulness of a 16S rDNA real-time PCR to monitor neonatal sepsis and to assist in medical decision to discontinue antibiotics(2016) STRANIERI, Ines; KANUNFRE, Kelly Aparecida; RODRIGUES, Jonatas Cristian; YAMAMOTO, Lidia; NADAF, Maria Isabel Valdomir; PALMEIRA, Patricia; OKAY, Thelma SuelyObjective: To monitor the bacterial load in newborns with proven infections on the day of admission, 48 h and 7 days after treatment. Methods: Real-time PCR (qPCR) targeting the 16S rDNA. Results: The study recruited 17 newborns and the bacterial load was in general low (<50 CFU/mL). In three of four deaths, the bacterial load values increased, and in 11 of the 13 survivors the values decreased until the third evaluation. Conclusion: Considering the extreme sensitivity and high negative predictive value of qPCR, this test could help to monitor the treatment of neonatal sepsis and to assist in medical decision to discontinue antibiotics.