Sandrine Comparsi Wagner

Triagem neonatal para hemoglobinopatias: experiência de um ano na rede de saúde pública do Rio Grande do Sul, Brasil

Hemoglobinopathies are the most common inherited disorders in humans; the most frequent are hemoglobins S and C (Hb S and Hb C). Studies in Brazil show the high prevalence of Hb S and Hb C heterozygotes, indicating the need for diagnosis to allow medical care and suitable genetic counseling. This study evaluates the prevalence of hemoglobin patterns in different areas of Rio Grande do Sul State, Brazil, using neonatal data from the public health system. Blood samples from 117,320 newborns, obtained by heel stick, and 2,389 blood samples from parents of newborns, obtained by venopuncture, were submitted to IEF and HPLC. Among the newborns, 1,629 (1.4%) showed abnormal hemoglobin patterns: 1,342 FAS; 225 FAC; 45 FAD; 2 FSC; 1 FS and 26 variant hemoglobin heterozygotes. We conclude that the methods used are able to identify a broad variety of hemoglobin patterns with high specificity and sensitivity. The information is of paramount importance for transmitting knowledge in the public health field, besides facilitating planning and resource allocation.

Identification of β thalassemia mutations in South Brazilians

We have evaluated the mutation profile in a sample of 127 unrelated β-thalassemia (β thal) individuals, diagnosed through A2 and fetal hemoglobin quantification by high-performance liquid chromatography (HPLC) from the Brazilian southernmost state, where a flow of Italian immigrants had occurred in the late 19th century, mainly from Northern Italy. The molecular analysis was performed by DNA sequencing of the most common mutations found in the Mediterranean region. The β0 codon 39 nonsense mutation was the most frequent alteration (50.9%), followed by β+ IVSI 110 G>A (18.1%), β0 IVSI 1 G>A (12.9%), β+ IVSI 6 T>C (9.5%), and other rare mutations (8.6%). The chosen gene sequence was able to identify 91% β-thal mutations in the population studied, showing some similarity with allele frequencies of the mainly colonizing countries of Rio Grande do Sul state. The comparison of our results to other Brazilian studies has shown significant differences. Therefore, we can conclude that the genotypic profile of β-thal shows great variability. Hence, it would be arbitrary to infer regional study results as being representative of the Brazilian whole population. Brazilian researchers of different regions should identify their most frequent genotypes to provide better understanding on this disease and state adequate public health policies.

Diagnóstico laboratorial das leucemias mielóides agudas

Acute lymphoid leukemia (ALL) is the commonest type of cancer in childhood, representing 70% of cases. In adults its incidence is 20% only. The initial diagnosis approach consists of a peripheral blood and bone marrow cytomorphological examination. The rate of correctly classified cases is increased up to 99% through immunophenotypic study, which allows to identify the cell line (T or B) and the different stages of cell maturation. Nearly 20% derive from T cells, 75% from B-cell precursors and 5% from mature B-cells. The cytogenetic techniques have markedly contributed to the better understanding of molecular biology and ALL treatment. Chromosomal abnormalities, associated with the immunophenotyping panel, are the most important parameter for leukemia classification. Together with clinical and in vitro factors, this parameter allows the patients stratification in different risk groups, which is of great importance for establishing a prognosis and a suitable treatment. The aim of this study was to perform a bibliographic review of the laboratory methods by morphological, cytochemical, immune, cytogenetic and molecular genetic patterns, which are useful tools for acute lymphoid leukemia classification and diagnosis.

Monitoring imatinib plasma concentrations in chronic myeloid leukemia

Imatinib has proved to be effective in the treatment of chronic myeloid leukemia, but plasma levels above 1,000 ng/mL must be achieved to optimize activity. Therapeutic drug monitoring of imatinib is useful for patients that do not present clinical response. There are several analytical methods to measure imatinib in biosamples, which are mainly based on liquid chromatography with mass spectrometric or diode array spectrophotometric detection. The former is preferred due to its lower cost and wider availability. The present manuscript presents a review of the clinical and analytical aspects of the therapeutic drug monitoring of imatinib in the treatment of chronic myeloid leukemia. The review includes references published over the last 10 years. There is evidence that the monitoring of plasmatic levels of imatinib is an useful alternative, especially considering the wide pharmacokinetic variability of this drug.

Neonatal screening for hemoglobinopathies: results of a public health system in South Brazil.

AIM The aim of this study was to estimate the prevalence of hemoglobinopathies in South Brazil. METHODS Samples of dried blood spots collected by heel prick in neonates were evaluated by isoeletric focusing and/or high-performance liquid chromatography techniques. All variants were characterized at the molecular level. RESULTS A total of 437,787 samples were evaluated. Among these, 6391 showed an abnormal hemoglobin pattern. These included 48 cases (0.01%) of sickle cell disorders (33 hemoglobin SS [Hb SS], 7 Hb SC, 7 Hb S/beta thalassemia, 1 Hb SD), 1 neonate who was homozygous for beta thalassemia, 6272 (1.4%) newborns who were heterozygous for Hb S, C, or D, and 71 (0.02%) neonates who were carriers for rare hemoglobin variants. Most of these rare variants were identified for the first time in Brazil. CONCLUSIONS Comparing these results with those obtained in other Brazilian regions, we observe a highly heterogeneous distribution. This knowledge is useful in healthcare planning and allocation of resources, as well as identifying at-risk couples, which will assist with disease prevention.

DBS sampling in imatinib therapeutic drug monitoring: from method development to clinical application

BACKGROUND Imatinib (IM) is widely used in treatment of chronic myeloid leukemia with target trough plasma concentrations above 1000 ng ml(-1). DBS can increase access to IM therapeutic drug monitoring. RESULTS IM was measured in the range 50-4000 ng ml(-1) by UHPLC-MS/MS using one 6 mm DBS in a fully validated method. IM was stable at DBS maintained at 40°C for 36 days. Plasma and DBS concentrations were highly correlated (r > 0.96). The use of a IM concentration target of 765 ng ml(-1) in DBS identified 93% of patients with plasma concentration below 1000 ng ml(-1). CONCLUSION IM can be measured in DBS using UHPLC-MS/MS with results comparable to those obtained in blood plasma.

Associação entre fatores de risco cardiovascular e proteína C-reativa em mulheres idosas

BACKGROUND: The inflammatory process plays an important role in the etiology of cardiovascular diseases. Several studies have shown that high levels of C-reactive protein (CRP), a hepatic acute phase protein, are associated with the risk of such diseases. OBJECTIVES: In this study we investigated the existence of association between CRP and cardiovascular risk factors in elderly women. MATERIAL AND METHOD: Anthropometric data, body impedance, blood pressure, lipid profiles, fasting glucose and CRP levels were evaluated. RESULTS: We observed that CRP was linked with body mass index (p = 0.001) and body fat percentage (p = 0.015) and there was no significant connection with any other studied variable. DISCUSSION: The association between CRP and measures of obesity is a consensus in literature. However, it may not show a true progression of atherosclerosis or an inflammatory state. Regarding the inexistence of association with other cardiovascular risk factors observed in this study, the gathered data are conflicting. Some authors indicate correlation between PCR and such factors, whereas others point out its inexistence. CONCLUSIONS: This study demonstrates the association of CRP with obesity, but not with other cardiovascular risk factors.

Prevalência de anemia em trabalhadores expostos ocupacionalmente ao chumbo

O chumbo e um dos elementos mais abundantes da natureza. Atualmente o chumbo e muito utilizado na manufatura de baterias, latao e bronze, radiadores, soldas, cabos, tintas, corantes, cerâmicas, municao, entre outros. A intoxicacao do chumbo e chamada de saturnismo e esta na maioria das vezes relacionada a atividade profissional. O chumbo pode causar alteracoes neurologicas, hematologicas, renais, cardiacas e reprodutivas. O objetivo deste trabalho foi comparar os niveis sanguineos de 53 trabalhadores expostos ocupacionalmente ao chumbo, com grupo controle nao exposto a agentes quimicos ou fisicos, avaliando dosagem de chumbo serico, contagem de eritrocitos, hematocrito, dosagem de hemoglobina e idade. Com relacao ao chumbo serico, dentre o grupo exposto ocupacionalmente ao metal, 20,8% dos trabalhadores apresentavam valores ate 40 µg/dL, 35,8% obtiveram resultados entre 40 µg/dL e 60 µg/dL, e 43,4% apresentaram valores de chumbo serico acima de 60 µg/dL. Ja no grupo controle, todas as amostras apresentaram valores abaixo de 40 µg/dL de chumbo serico. Com relacao a hemoglobina, 7,5% dos trabalhadores do grupo controle e 34,0% dos expostos apresentaram valores abaixo de 13 g/dL, com diferenca estatisticamente significativa. Os resultados indicam que niveis elevados de chumbo estao relacionados com valores de hemoglobina abaixo dos indices de referencia.

Prevalence of UGT1A1 Gene Polymorphism in Patients with Hemolytic Anemia in Southern Brazil

The aim of the work was to determine the variation of UGT1A1 genotypes in patients with hemolytic anemia in the southern Brazil. Three hundred twenty-three patients with hemolytic anemia were genotyped for UGT1A1 along with 232 controls. Allelic and genotypic distribution did not differ among studied groups. The TA7/TA7 genotype presented a frequency that ranged from 3.2% to 18.0% (nonsignificant). Alleles TA5 and TA8 were also found in the sample, even though southern Brazil is a major Caucasoid region. Genotype prevalence was very similar to those of African origins, reflecting the diversity of ethnic origins and the high degree of admixture in southern Brazil. Further studies should be conducted to correlate the modulating role of UGT1A1 polymorphism with the clinical conditions of each patient with hemolytic anemia.

Laboratory diagnosis of acute myeloid leukemias

The acute leukemias are characterized by the clonal proliferation and maturative blockage of hematopoietic cells, with diffuse substitution of the bone marrow by neoplasic cells. The acute myeloid leukemia (AML) is a heterogeneous group of clonal disease in the hematopoietic tissue and predominantly affects people older than 60. The AML has eight morphologically different subtypes: AML M0 to M7. The diagnostic methods for identification of AML and subtypes classification are based on morphological, cytochemical and immunophenotyping patterns, besides genetic and molecular analyses. The diagnosis of leukemia is important to the lineage differentiation in AML or ALL and also for the identification of biphenotypic acute leukemia (BAL). The aim of this study was to perform a bibliographic review of AML, giving emphasis on laboratory methods useful for its identification and differentiation.