The landscape of hematology research in Brazil: an analysis of data from citation databases

ABSTRACT Introduction: Scientometrics is the field concerned with measuring and analyzing academic literature, using specific metrics and data from bibliometric databases. Hematology is a broad area of science and medicine, from which several landmark scientific discoveries have emerged. Objective: The aim of this report is to provide a snapshot of the landscape of hematology research in Brazil, based on a comprehensive analysis of published studies in hematology whose authors were affiliated to Brazilian institutions from 1980 to 2020. Method: Articles, reviews and letters to the editor with at least one author affiliated to a Brazilian institution were retrieved from Incytes/Web of Science or Scopus databases. Importantly, only papers classified in the subject area "Hematology" by the embedded algorithms of each database were included. Results: Considering all published papers, Brazil is in the 22nd position, contributing with around 1.1% of papers in this period. A clear and sustained increase in publication output can be observed from the early 1990's to the present moment. Publicly-funded higher education institutions were the main contributors to the development and consolidation of the hematology scientific community, which has grown in diversity, with an increasing number of contributions from private institutions. In regard to funding, public agencies have been and remain by large as the most important funder of research in hematology in Brazil. Conclusion: We suggest that continuous monitoring of the temporal trends of some of the data compiled in our report could potentially contribute to a clearer picture of the development of hematology research in Brazil.

Career paths and workforce diversity in hematology: A cross-sectional study of a 35-year alumni cohort from an academic residency program in Brazil

ABSTRACT Introduction: Although not mandatory, medical residency has become a sine qua non condition for practicing in most medical specialties in Brazil. Residency programs are hosted mainly by university accredited academic centers and hospitals in the national public healthcare system, under guidance and accreditation by a national commission. Despite the importance of these programs for the development of the hematology workforce, few studies have addressed their characteristics and impact on society. Methods: We performed a comprehensive cross-sectional survey of a 35-year alumni cohort from a hematology academic residency program in Brazil. Results: In total, 86/98 (87.8%) responded to the survey. The mean age at residency completion was 28.5 years, 60.5% of the alumni were women and sixty-four (74.4%) self-declared their skin color as white. Higher rates of parental education attainment and low rates of trainee financial dependence were observed and these patterns were stable over time. While the proportion of trainees from other states increased steadily, the number of hematologists practicing in other states remained stable. Approximately half of the alumni worked both in the private and public sectors, mainly in malignant hematology and in outpatient clinics. Twenty-five percent of the alumni reported prior leadership and teaching positions, mainly as directors of transfusion services. Conclusion: Our results provide data that can be potentially useful for policymakers and curricular development in the planning of strategies concerning the future workforce of hematologists.

Oral mucositis and microbial status in acute lymphoblastic leukemia subjects undergoing high-dose chemotherapy

Aim: To assess oral microbial status in patients with acute lymphoblastic leukemia (ALL) undergoing high-dose chemotherapy and to unravel possible associations between nosocomial pathogens and the establishment of chemotherapy-induced oral mucositis (CIOM). Methods: Oral mucosa, saliva, and peripheral blood samples were collected from 46 ALL subjects one day prior to chemotherapy (D0) and 2 weeks after treatment initiation (D14). Clinical intraoral inspection was performed by a single practitioner, with mucositis classification performed according to the WHO oral toxicity scale. Blood components were quantified by automatic flow cytometry, while oral Staphylococcus aureus and Pseudomonas aeruginosa were detected by Polymerase Chain Reaction with species-specific primers. Associations among bacteria and clinical findings were determined by Fisher's Exact test, longitudinal bacterial changes by paired Macnemar, and correlations among blood parameters and mucositis status or bacteria via Mann-Whitney. Results: S. aureus displayed higher detection rates at D14 (p < 0.05) and was positively associated with mucositis, adoption of a non-solid diet (all p < 0.001), nausea and fever (all p < 0.05). Conversely, P. aeruginosa did not correlate to CIOM clinical parameters. At the systemic standpoint, lower hemoglobin levels associated with CIOM and fever events (all p < 0.01). Conclusion: The study evidences S. aureus as a potential pathogen in ALL-CIOM, reaffirming microbial control as an important preventive measure during high-dose immunosuppressive therapy. The weight of non-white-blood-cell parameters should be validated as novel CIOM biomarkers in prospective research

Neurological manifestations in thrombotic microangiopathy: Imaging features, risk factors and clinical course.

BACKGROUND AND PURPOSE: Thrombotic microangiopathy (TMA) is a group of microvascular occlusive disorders that presents with neurological involvement in up to 87% of the cases. Although the central nervous system (CNS) is an important target organ in TMA, the role of neurological manifestations in the disease clinical course is not well established. In this study, we described the neurological manifestations and CNS radiological aspects in patients with a first, acute TMA event. We also examined the association between severe neurological involvement and adverse clinical outcomes in TMA. METHODS: A cohort of patients diagnosed with a first TMA event between 1995 and 2016 was included, their medical charts and imaging tests were retrospectively evaluated. RESULTS: A total of 49 patients were included, 85.7% were women and the mean age was 36.5 years-old (SD 13.0). Neurological manifestations were described in 85.7% of the patients, most of them (88%) were considered severe and consisted of confusion, compromised sensorimotor function, stupor, seizures, and personality change. Imaging tests were performed in 62% of the patients with neurological manifestations and detected acute CNS lesions, such as posterior reversible encephalopathy syndrome, hemorrhagic and ischemic stroke were observed, in 7 (27%) of them. While the need for intensive care unit admission was greater and longer among patients with severe neurological manifestations, the number of plasma exchange sessions, the total duration of hospitalization and in-hospital death were similar between groups. CONCLUSIONS: Severe neurological manifestations are common in first TMA events and are responsible for a worse disease presentation at admission. While the effect of neurological manifestations on acute TMA clinical course seems to be modest, these manifestations may have an important impact on the development of chronic cognitive impairment, which highlights the need for proper diagnosis and treatment.

Increased inflammation and endothelial markers in patients with late severe post-thrombotic syndrome.

INTRODUCTION: Post-thrombotic syndrome (PTS) is a limiting long-term complication present in 20-50% of patients with deep venous thrombosis (DVT) of the lower limbs. A panel of biomarkers with potential relevance to enhance knowledge on the pathophysiology of PTS was investigated. METHODS: This case-control study included 93 patients with DVT in the lower limbs, 31 with severe PTS (cases) and 62 with mild/no PTS (controls), over 24 months after an acute episode. Thirty-one healthy individuals (HI) with no history of DVT were included as a reference to the population. FVIII activity, D-dimer, inflammatory cytokines, endothelial dysfunction markers, matrix metalloproteinases, and their inhibitors, tissue remodeling and growth factor levels were evaluated. The classification of PTS was, by the Villalta scale. RESULTS: Patients with severe PTS showed elevated levels of CRP, sICAM-1, sE-selectin, and decreased MMP-9 and MCP-1 levels when compared to patients with mild/no PTS. Moreover, DVT patients presented higher levels of FVIII and D-dimer when compared to HI. CONCLUSIONS: DVT patients present an inflammatory status, endothelial dysfunction and altered proteolysis MMPs activity, even a long time after the acute thrombotic episode, which is more significant in severe PTS. These results suggest a possible role of these mediators in the maintenance and worsening of PTS severity.

Laboratory evaluation of patients with undiagnosed bleeding disorders.

The evaluation of patients with a bleeding tendency represents a challenge as the routinely available tests for evaluating bleeding disorders are limited, complicating the laboratory determination of the clinically observed bleeding tendency. As a result, some bleeding disorders remain undiagnosed. The aim of the study was to evaluate whether global coagulation tests would contribute to the laboratory analysis of patients with undiagnosed bleeding disorders. Patients were evaluated for coagulation and fibrinolysis activities by thrombin generation test and euglobulin lysis time. In addition, plasma activity of factor XIII, plasminogen, α-2 antiplasmin, plasminogen activator inhibitor-1, and thrombin-activatable fibrinolysis inhibitor was also obtained. Forty-five patients were included. Eight per cent presented a mild bleeding disorder and 20% a moderate bleeding disorder. The thrombin generation test results were similar between patients and controls. Euglobulin lysis time results, however, were lower in patients than in controls, both before (median 175 vs. 250 min, respectively; P = 0.003) and after (median 145 vs. 115 min, respectively; P ≤ 0.001) arm constriction, suggesting that they were experiencing hyperfibrinolysis. Interestingly, patients' median thrombin-activatable fibrinolysis inhibitor activity was higher than in controls (21.2 vs. 19.46 µg/ml; P = 0.016). However, plasminogen, α-2 antiplasmin, plasminogen activator inhibitor-1, and factor XIII activities did not differ between the groups. Global coagulation and fibrinolysis tests proved to be limited in detecting the hemostatic disorders in some patients with a relevant bleeding tendency and may not be adequate to address their bleeding risk. Bleeding scores are currently the available medical approach for the evaluation of these patients.

Acquired thrombotic thrombocytopenic purpura due to antibody-mediated ADAMTS13 deficiency precipitated by a localized Castleman's disease: a case report.

Acquired ADAMTS13 inhibitor causing thrombotic thrombocytopenic purpura (TTP) may be precipitated by some infections, inflammatory diseases or neoplasia. We reported a case of refractory TTP precipitated by a newly diagnosed localized Castleman's disease (CD). TTP was initially treated with plasma exchange and immunosuppressive therapy with corticosteroids; however the treatment failed to promote sustained response. During hospitalization, an abdominal tumor was diagnosed and resected; the histological analysis revealed a CD of hyaline-vascular variant rich stroma. After tumor removal, the patient achieved a long-lasting clinical remission and normalized ADAMTS13 activity. This clinical case describes a novel association of acquired ADAMTS13 inhibitor and CD. The antibody to ADAMTS13 developed along with the systemic manifestation of CD and promptly disappeared after the resection of the tumor. There are reports of neoplasia-associated thrombotic microangiopathy however direct evidence of CD-dependent ADAMTS13 inhibitor had not yet been reported.