Roberto Zulli

Mutações do gene cystic fibrosis transmembrane conductance regulator e deleções dos genes glutationa S-transferase em pacientes com fibrose cística no Brasil

OBJECTIVE To determine the effects that mutation of the cystic fibrosis transmembrane conductance regulator (CFTR) gene and deletion of the glutathione S-transferase (GST) genes mu-1 (GSTM1) and theta-1 (GSTT1) have on the clinical course of cystic fibrosis (CF) in patients residing in the southeastern region of Brazil. METHODS The study sample consisted of all consecutive CF patients treated at the Hospital de Clínicas School of Medical Sciences of the State University at Campinas between March of 2002 and March of 2005. We included 66 CF patients. Genomic DNA was analyzed by polymerase chain reaction and restriction endonuclease digestion for the identification of the genotypes. RESULTS The DF508 mutation of the CFTR gene was found in 44 patients (66.7%). The null genotypes GSTM1, GSTT1 and GSTM1/GSTT1 were found in 40.9%, 15.2%, and 3.0% of the patients, respectively. The DF508 CFTR mutation was more common in patients diagnosed with CF before 2.5 years of age than in those diagnosed later (75.5% vs. 41.2%; p = 0.008). The frequency of the DF508 CFTR mutation, as well as of the GSTM1 and GSTT1 genotypes, was not found to be associated with gender, ethnicity, pulmonary disease status, or pancreatic disease status. CONCLUSIONS When the patients were stratified by clinical and epidemiological features, the frequencies of the GSTM1 and GSTT1 null genotypes were similar, suggesting that the inherited absence of these enzymatic pathways does not alter the course of CF. However, the high frequency of the DF508 CFTR mutation found in younger children suggests that it influences the age at diagnosis of CF in this region of Brazil.

Major salivary gland damage in allogeneic hematopoietic progenitor cell transplantation assessed by scintigraphic methods

Salivary gland dysfunction is a common sequela of hematopoietic progenitor cell transplantation (HPCT). The investigation of major salivary gland dysfunction with sodium pertechnetate scintigraphy is a non-invasive method that provides images of the parotid and submandibular glands. In this prospective trial, 20 HPCT patients were submitted to scintigraphic study with 99mTc-pertechenate and 67Ga in order to evaluate the major salivary glands early involvement following HPCT. Major salivary glands were evaluated prior to HCPT as well as at Days +30, +60 and +100 post transplant. Major salivary glands uptake and clearance of 99mTc-pertechenate results did not demonstrate any functional differences between pre- versus post transplant periods. Results of the 67Ga scan revealed inflammatory infiltration following HPCT, primarily in submandibular glands, suggest a persistent involvement of major salivary glands up to Day +100 after HPCT.

New mutations detected by denaturing high performance liquid chromatography during screening of exon 6 bcr-abl mutations in patients with chronic myeloid leukemia treated with tyrosine kinase inhibitors

Point mutations within the ABL kinase domain are the most frequent mechanism for reactivation of kinase activity of the BCR-ABL gene and have been associated with clinical resistance to tyrosine kinase (TK) inhibitors in patients with CML, conferring a poor prognosis. T315I (Treonine→Isoleucine) is a mutation in the exon 6 of BCR-ABL gene that makes the protein resistant to kinase inhibitors currently used for treating CML. Denaturing High-performance liquid chromatography (D-HPLC) allows for high throughput mutation screening. In this study, we screened mutations in exon 6 of the BCR-ABL gene in patients presenting failure or sub optimal response according to Leukemia Net criteria and correlated the presence of mutations with clinical outcome. Genomic DNA was extracted from peripheral blood samples from 93 patients with CML (5 intolerant and 88 resistant). The PCR product was analysed by D-HPLC, and the patients samples with abnormal D-HLPC profiles were submitted to automated sequencing, using specific primers. Overall survival (OS) was calculated from the date of mutation analysis, for the whole group and for both groups (mutation versus no mutation). We screened mutations in exon 6 of the BCR-ABL gene in 93 CML TKI - resistant patients. Twenty-three out of 93 samples (25%) showed an abnormal elution profile. Automated sequencing confirmed the presence of a nucleotide change in 19 out of 23 cases: one polymorphism, T315T, seven known point mutations: T315I, F317L, V339L, M351T, E355G and F359V and three novel mutations: C305R, D325D and I360S. OS for the whole group was 80% in a median observation time of 30 months. OS for patients without the mutation was 87% and with the mutation was 56%, in a median observation time of 37 and 10 months, respectively (p < 0.0001, RR = 68). D-HPLC is a practical and sensitive method for routine clinical monitoring for emergence of kinase domain mutations and may be useful for optimising therapy in CML. The screening of mutations in exon 6 is clinically relevant, once the presence of mutations confers a poor outcome. Early detection of emerging mutant clones may help in decision-making for alternative treatment.

The new noninvasive occlusion spectroscopy hemoglobin measurement method: a reliable and easy anemia screening test for blood donors

BACKGROUND: The tests used for anemia screening in blood donors are based on fingerstick samples, leading to discomfort and complaints. The aim of this study was to analyze the feasibility of occlusion spectroscopy method in blood banks and to compare the method with fingerstick hemoglobinometer and hemoglobin (Hb) determination on an automatic blood analyzer.

Identification of platelet refractoriness in oncohematologic patients

OBJECTIVES: To identify the occurrence and the causes of platelet refractoriness in oncohematologic patients. INTRODUCTION: Platelet refractoriness (unsatisfactory post-transfusion platelet increment) is a severe problem that impairs the treatment of oncohematologic patients and is not routinely investigated in most Brazilian services. METHODS: Forty-four episodes of platelet concentrate transfusion were evaluated in 16 patients according to the following parameters: corrected count increment, clinical conditions and detection of anti-platelet antibodies by the platelet immunofluorescence test (PIFT) and panel reactive antibodies against human leukocyte antigen class I (PRA-HLA). RESULTS: Of the 16 patients evaluated (median age: 53 years), nine (56%) were women, seven of them with a history of pregnancy. An unsatisfactory increment was observed in 43% of the transfusion events, being more frequent in transfusions of random platelet concentrates (54%). Platelet refractoriness was confirmed in three patients (19%), who presented immunologic and non-immunologic causes. Alloantibodies were identified in eight patients (50%) by the PIFT and in three (19%) by the PRA-HLA. Among alloimmunized patients, nine (64%) had a history of transfusion, and three as a result of pregnancy (43%). Of the former, two were refractory (29%). No significant differences were observed, probably as a result of the small sample size. CONCLUSION: The high rate of unsatisfactory platelet increment, refractoriness and alloimmunization observed support the need to set up protocols for the investigation of this complication in all chronically transfused patients, a fundamental requirement for the guarantee of adequate management.