Lucia Mariano da Rocha Silla

Epidemiology of bacteremia and factors associated with multi-drug- resistant gram-negative bacteremia in hematopoietic stem cell transplant recipients

The incidence of Gram-negative bacteremia has increased in hematopoietic stem cell transplant (HSCT) recipients. We prospectively collected data from 13 Brazilian HSCT centers to characterize the epidemiology of bacteremia occurring early post transplant, and to identify factors associated with infection due to multi-drug-resistant (MDR) Gram-negative isolates. MDR was defined as an isolate with resistance to at least two of the following: third- or fourth-generation cephalosporins, carbapenems or piperacillin-tazobactam. Among 411 HSCT, fever occurred in 333, and 91 developed bacteremia (118 isolates): 47% owing to Gram-positive, 37% owing to Gram-negative, and 16% caused by Gram-positive and Gram-negative bacteria. Pseudomonas aeruginosa (22%), Klebsiella pneumoniae (19%) and Escherichia coli (17%) accounted for the majority of Gram-negative isolates, and 37% were MDR. These isolates were recovered from 20 patients, representing 5% of all 411 HSCT and 22% of the episodes with bacteremia. By multivariate analysis, treatment with third-generation cephalosporins (odds ratio (OR) 10.65, 95% confidence interval (CI) 3.75–30.27) and being at one of the hospitals (OR 9.47, 95% CI 2.60–34.40) were associated with infection due to MDR Gram-negative isolates. These findings may have important clinical implications in the decision of giving prophylaxis and selecting the empiric antibiotic regimen.

Invasive fungal diseases in haematopoietic cell transplant recipients and in patients with acute myeloid leukaemia or myelodysplasia in Brazil

Invasive fungal disease (IFD) shows distinct regional incidence patterns and epidemiological features depending on the geographic region. We conducted a prospective survey in eight centres in Brazil from May 2007 to July 2009. All haematopoietic cell transplant (HCT) recipients and patients with acute myeloid leukaemia (AML) or myelodysplasia (MDS) were followed from admission until 1 year (HCT) or end of consolidation therapy (AML/MDS). The 12-month cumulative incidence (CI) of proven or probable IFD was calculated, and curves were compared using the Grey test. Among 237 AML/MDS patients and 700 HCT recipients (378 allogeneic, 322 autologous), the 1-year CI of IFD in AML/MDS, allogeneic HCT and autologous HCT was 18.7%, 11.3% and 1.9% (p <0.001), respectively. Fusariosis (23 episodes), aspergillosis (20 episodes) and candidiasis (11 episodes) were the most frequent IFD. The 1-year CI of aspergillosis and fusariosis in AML/MDS, allogeneic HCT and autologous HCT were 13.4%, 2.3% and 0% (p <0.001), and 5.2%, 3.8% and 0.6% (p 0.01), respectively. The 6-week probability of survival was 53%, and was lower in cases of fusariosis (41%). We observed a high burden of IFD and a high incidence and mortality for fusariosis in this first multicentre epidemiological study of IFD in haematological patients in Brazil.

Mesenchymal stem cell therapy and acute graft-versus-host disease: a review.

Mesenchymal stem cells (MSCs) are being widely studied as potential cell therapy agents due to their immunomodulatory properties, which have been established by in vitro studies and in several clinical trials. Within this context, mesenchymal stem cell therapy appears to hold substantial promise, particularly in the treatment of conditions involving autoimmune and inflammatory components. Nevertheless, many research findings are still contradictory, mostly due to difficulties in characterization of the effects of MSCs in vivo. The purpose of this review is to report the mechanisms underlying mesenchymal stem cell therapy for acute graft-versus-host disease, particularly with respect to immunomodulation, migration, and homing, as well as report clinical applications described in the literature.

Neonatal screening for hemoglobinopathies: a pilot study in Porto Alegre, Rio Grande do Sul, Brazil

Following a previous evaluation of concept, item and semantic equivalences, this paper assesses the measurement equivalence between a Portuguese version of Revised Conflict Tactics Scales (CTS2) and the original instrument conceived in English. The CTS2 has been widely used to tap violence between couples. An intra-observer reliability evaluation involved 165 replications carried out within a 24-48 hour period. Kappa point-estimates were above 0.75 for all scales except sexual coercion. The analysis of internal consistency concerned 768 subjects with complete sets of items. Kuder-Richardson-20 estimates ranged from 0.65 to 0.86. Results were similar to those found in the original instrument in English for the negotiation, psychological aggression and physical violence scales, yet not so for the sexual coercion and injury scales. Factor analysis identified factors with a recognizable correspondence to the underlying dimensions, although a few inconsistencies were detected. For the assessment of construct validity (n = 528) associations between the instruments scales were evaluated, as well as the relationships between violence and putative underlying dimensions. Overall, the findings suggest that the version can be used in the Brazilian context, although further investigation should be carried out to unveil some important remaining issues.This study was conducted to establish the frequency of hemoglobinopathies among newborns undergoing screening tests for metabolic diseases at the University Hospital (Hospital de Clínicas) in Porto Alegre, Rio Grande do Sul, Brazil. Testing for abnormal hemoglobins was performed by isoelectric focusing electrophoresis on agarose gel with blood obtained by heel stick and applied to filter paper. For confirmatory testing of abnormal neonatal screening, a venopuncture blood sample was obtained from the infant and parents and then submitted to hemoglobin electrophoresis on cellulose acetate at pH 8.6 and citrate agar at pH 6.2. A total of 1,615 subjects were studied: 20 samples showed the Hb S pattern and six samples showed Hb C. Thus, frequency of the sickle cell gene was 1.2% and that of the Hb C gene was 0.4%, regardless of race or origin. These data suggest that the inclusion of universal neonatal screening for hemoglobinopathies in the ongoing projects for the detection of phenylketonuria and congenital hypothyroidism has many advantages and should be considered in health programs.

Expression of CD55 and CD59 on peripheral blood cells from systemic lupus erythematosus (SLE) patients.

CD55 and CD59 are glycosylphosphatidylinositol-anchored proteins with complement inhibitory properties. CD55 inhibits the formation of C3 convertases, and CD59 prevents the terminal polymerisation of the membrane attack complex. It has been reported that SLE patients seems to have an acquired deficiency of these proteins associated with secondary autoimmune haemolytic anaemia and lymphopenia. The aim of this study was to evaluate the presence of altered CD55 and CD59 expression on peripheral blood cells from SLE patients. Flow cytometric analyses were performed on red and white blood cells from 23 SLE patients and 23 healthy controls. We observed more CD55- and CD59-lymphocytes (p=0.005 and p=0.019, respectively), and CD59-granulocytes (p=0.045) in SLE patients than in controls. These results suggest there is an altered pattern of CD55 and CD59 expression on the peripheral blood cells of SLE patients, and it may play a role in the cytopenias in these patients.

Lack of imatinib-induced thyroid dysfunction in a cohort of non-thyroidectomized patients.

Lack of imatinib-induced thyroid dysfunction in a cohort of non-thyroidectomized patients Jose Miguel Dora, Murilo Anderson Leie, Bruno Netto, Laura Maria Fogliatto, Lucia Silla, Felipe Torres and Ana Luiza Maia Endocrine Division, Thyroid Section, Hospital de Clinicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil, Hematology Division and Radiology Division, Hospital de Clinicas de Porto Alegre, Porto Alegre, Brazil

Triagem neonatal para hemoglobinopatias: um estudo piloto em Porto Alegre, Rio Grande do Sul, Brasil

This study was conducted to establish the frequency of hemoglobinopathies among newborns undergoing screening tests for metabolic diseases at the University Hospital (Hospital de Clinicas) in Porto Alegre, Rio Grande do Sul, Brazil. Testing for abnormal hemoglobins was performed by isoelectric focusing electrophoresis on agarose gel with blood obtained by heel stick and applied to filter paper. For confirmatory testing of abnormal neonatal screening, a venopuncture blood sample was obtained from the infant and parents and then submitted to hemoglobin electrophoresis on cellulose acetate at pH 8.6 and citrate agar at pH 6.2. A total of 1,615 subjects were studied: 20 samples showed the Hb S pattern and six samples showed Hb C. Thus, frequency of the sickle cell gene was 1.2% and that of the Hb C gene was 0.4%, regardless of race or origin. These data suggest that the inclusion of universal neonatal screening for hemoglobinopathies in the ongoing projects for the detection of phenylketonuria and congenital hypothyroidism has many advantages and should be considered in health programs.

Imatinib mesylate versus allogeneic BMT for patients with chronic myeloid leukemia in first chronic phase.

Imatinib mesylate (IM) is now first-line treatment for CML. To study the results of treatment with IM after IFN failure/intolerance versus allogeneic BMT (allo-BMT), we retrospectively analyzed 264 patients treated for CML in first chronic phase in three different institutions. Over a 6-year period (2001–2006), 174 patients received IM after failure of or intolerance to IFN. During the same period of time, 90 patients received an allo-BMT from an HLA-matched sibling (n=83) or an unrelated donor (n=7). The IM group was older (41 versus 33 years, P<0.001). Five-year EFS was 62% among patients receiving IM and 52% among patients undergoing allo-BMT (P=0.0002). OS at 5 years was 93% for IM-treated patients and 59% for patients undergoing allo-BMT (P<0.0001). Allo-BMT cannot be considered as first-line treatment for CML patients in first chronic phase.

Patient socioeconomic status as a prognostic factor for allo-SCT

The aim of the present study was to assess the influence of socioeconomic status (SeS) on the outcome of allo-SCT at a Brazilian SCT center. In total, 201 patients receiving HLA-identical related allo-SCTs were studied. The median age was 30 years. Overall, 163 patients had malignancies (CML 68, ALL/AML 63, myelodysplastic syndrome 12 and others 20). SeS was defined according to the Brazilian Association of Market Research Agencies classification, where people are clustered in groups A–E (richest to poorest). In total, 146 patients (72%) were classified as richest (A+B+C) and 55 (28%) as poorest (D+E). The D+E SeS group was associated with a higher incidence of chronic GVHD and acute GVHD (hazard ratio (HR)=2.61; P=0.001 and HR=2.62; P=0.001, respectively), better platelet and neutrophil engraftment (HR=1.94; P=<0.001 and HR=2.12; P=0.001) and with a higher TRM in multivariate analysis (HR=1.92; P=0.039). Estimated overall survival at 5 years was 55.2%. A D+E SeS (HR=2.13; P=0.001) was associated with a worse survival on multivariate analysis. In conclusion, a lower SeS is a strong prognostic factor in patients undergoing allo-SCT in Brazil, influencing engraftment, TRM and overall survival.

Interleukin-15 favors the expansion of central memory CD8+ T cells in ex vivo generated, antileukemia human cytotoxic T lymphocyte lines.

We demonstrated in previous studies that interleukin (IL) -2 supports in vitro cell proliferation of donor-derived cytotoxic T lymphocyte (CTL) lines directed against different types of leukemia blasts. The aim of this study was to compare the capacity of IL-15 with that of IL-2 in supporting the proliferation and cytotoxic activity of antileukemia CTL cultures, and their influence on T-cell memory compartment differentiation. Antileukemia CTL lines were generated using donor-derived dendritic cells pulsed with apoptotic leukemia blasts, in the presence of IL-12 and IL-7, during the primary culture, and expanded through 2 rounds of leukemia-specific stimulation and 1 round of antigen-independent expansion, each supplemented with either IL-2 or IL-15. Both IL-2–supplemented (IL-2–CTLs) and IL-15–supplemented (IL-15–CTLs) lines contained predominant numbers of CD45RA−/CCR7− effector memory (TEM) and CD45RA+/CCR7− (TEMRA+) T cells. Significantly higher numbers (P<0.05) of CD8-positive central memory T cells (TCM), and higher expansion rate, together with comparable cytotoxic activity, were observed in IL-15–CTLs compared with IL-2–CTLs. Altogether, these results demonstrate that IL-15 enhances recovery of CTL activity, without loss of leukemia-directed specificity, and favors expansion of TCM CD8-positive cells, expected to exhibit long-term survival and differentiation capacity in vivo in the presence of a limited amount of antigen.