Quantitative MRI evaluation of bone marrow in sickle cell disease: relationship with haemolysis and clinical severity.

AIM: To evaluate bone marrow fat fraction using the Dixon technique (FFDix) of magnetic resonance imaging (MRI) as a potential biomarker of haemolysis and clinical severity in the overall assessment and follow-up of sickle cell disease (SCD) patients. MATERIAL AND METHODS: The present study was a cross-sectional study in which healthy individuals and SCD patients (matched for age, sex, and weight) were subjected to MRI of the lumbar spine and pelvis to quantify FFDix in the bone marrow using the Dixon technique. SCD severity was analysed by clinical and laboratory data, and an online calculator. A high degree of haemolysis was defined using the cut-off values haemoglobin (Hb) ≤10 g/dl, lactate dehydrogenase (LDH) ≥325 U/l, reticulocytes ≥3% and total bilirubin (TB) ≥1.2 mg/dl. Pearson's correlation, receiver operating characteristic (ROC) curve and binary logistic regression analysis were performed. RESULTS: Forty-eight SCD patients (26 homozygous: HbSS and 22 compound heterozygous: HbSC) and 48 healthy individuals participated in the study. FFDix was lower in SCD patients than in the control group, showing even lower values in the HbSS subtype and patients with a higher degree of haemolysis. HbSC patients with a higher degree of haemolysis using hydroxyurea (medium dosage 9.8 mg/kg/day) had lower FFDix. ROC curves and odds ratios for detecting patients with a higher degree of haemolysis at the different FFDix measurement sites demonstrated excellent performance: iliac bones (cut-off ≤16.75%, AUC = 0.824, p<0.001), femoral heads (cut-off ≤46.7%, AUC = 0.775, p=0.001), lumbar vertebrae (cut-off ≤7.8%, AUC = 0.755, p=0.002). CONCLUSION: Decreased FFDix is indicative of higher degree of haemolysis and SCD severity with great potential as a non-invasive biomarker contributing to the overall assessment and follow-up of SCD patients.

Co-infections and superinfections complicating COVID-19 in cancer patients: A multicentre, international study.

BACKGROUND: We aimed to describe the epidemiology, risk factors, and clinical outcomes of co-infections and superinfections in onco-hematological patients with COVID-19. METHODS: International, multicentre cohort study of cancer patients with COVID-19. All patients were included in the analysis of co-infections at diagnosis, while only patients admitted at least 48 h were included in the analysis of superinfections. RESULTS: 684 patients were included (384 with solid tumors and 300 with hematological malignancies). Co-infections and superinfections were documented in 7.8% (54/684) and 19.1% (113/590) of patients, respectively. Lower respiratory tract infections were the most frequent infectious complications, most often caused by Streptococcus pneumoniae and Pseudomonas aeruginosa. Only seven patients developed opportunistic infections. Compared to patients without infectious complications, those with infections had worse outcomes, with high rates of acute respiratory distress syndrome, intensive care unit (ICU) admission, and case-fatality rates. Neutropenia, ICU admission and high levels of C-reactive protein (CRP) were independent risk factors for infections. CONCLUSIONS: Infectious complications in cancer patients with COVID-19 were lower than expected, affecting mainly neutropenic patients with high levels of CRP and/or ICU admission. The rate of opportunistic infections was unexpectedly low. The use of empiric antimicrobials in cancer patients with COVID-19 needs to be optimized.

Genotoxic and mutagenic effects of methyl ether dillapiole on the development of Aedes aegypti (Diptera: Culicidae).

Dillapiole, extracted from Piper aduncum essential oil and its derivatives, has been shown to be a potential alternative to the control of Aedes aegypti, which has become resistant to synthetic insecticides. Methyl ether dillapiole (MED) and temephos (TM) were compared to complement the data on the genotoxicity and developmental changes of Ae. aegypti. Over four generations (G1 -G4 ), third stage larvae were treated with MED at 60, 80 and 100 µg/mL and TM at 0.002, 0.005 and 0.007 µg/mL for 4 h. Adult females were separated to estimate oviposition and hatching rates, and total egg length. Over the four generations, a significant reduction was recorded in oviposition and hatching rates, and in mean egg length (Tukey, P < 0.05), compared with the negative control (NC). Cytological slide preparations were done from adult oocytes and larval neuroblasts. The cumulative effects of genotoxic (bridges, budding and nuclear fragmentation) and mutagenic (micronucleus and chromosomal breakage) damage was observed in the neuroblasts and oocytes of exposed mosquitoes. Developmental changes and damage to the genome of MED-treated Ae. aegypti were greater than those caused by TM. Further studies should focus on understanding the effects of the MED molecule on Ae. aegypti.

Comparative metavirome analysis in polytransfused patients

Due to the high transfusion volume, polytransfused patients with sickle cell disease (SCD) and beta-thalassemia are constantly exposed to parenterally transmitted infections. Currently, we have little information about the virome of such patients and how the virological composition might be influenced by the hemotherapy procedures that these patients receive. The objective of this study was to compare the viral diversity between these two groups with respect to the viral abundance and how it might be affected by the specific conditions of these groups. We sequenced by next-generation sequencing (NGS) and compared the virome of 30 patients with beta-thalassemia major, 45 with SCD, and 16 blood donors from the Blood Center of Ribeirão Preto, Brazil. Predominantly, commensal viruses including Torque teno virus (TTV) genotypes and human pegiviris-1 (HPgV-1) were identified in each group. Strikingly, while HPgV-1 reads were dominant in the SCD group, thalassemic patients showed high TTV abundance, expressed both in viral reads and genotypes. We speculated that the commensal virome of polytransfused patients might be influenced by the transfusion frequency and disease characteristics and that commensal viruses might be used as important genetic biomarkers for these hematological disturbances. Nevertheless, more specific studies are necessary to confirm a relationship between blood virome and transfusion treatment.

Viral metagenomics in Brazilian multiply transfused patients with sickle cell disease as an indicator for blood transfusion safety.

BACKGROUND AND AIM: Patients with sickle cell disease (SCD) are submitted to multiple transfusions in order to increase the oxygen capacity of the blood, decrease blood viscosity, and suppress the sickling of the cells. Multiply transfused patients with SCD represent significant risk of acquiring parenterally transmitted infections. The analysis of the virome profile of high-risk multiply transfused patients with SCD can reveal the presence of parenterally transmitted viruses and therefore be used an indirect approach for evaluation of blood transfusion safety. MATERIALS AND METHODS: Blood samples were collected from 45 patients with SCD receiving multiple transfusions and analyzed by metagenomic analyses. The samples were assembled in pools f which were submitted to nucleic acids extraction and sequencing by Illumina NextSeq 550 equipment. For bioinformatic analysis, we used a specific in-house developed pipeline specialized in identification of emerging viruses. RESULTS: The virome composition of SCD patients revealed the presence of commensal viruses represented by anelloviruses and Human Pegivirus-1 (HPgV-1, GB virus C). Contaminant viral sequences belonging to human lentiviruses (rev, env genes), cytomegalovirus and murine leukemia virus were also identified and are attributed to vectors used in the laboratory practice. No novel or unsuspected pathogenic viruses were identified. CONCLUSION: This study evaluates for the first time the virome of multiply transfused patients with SCD. Exclusively genetic material of commensal viruses was annotated. Therefore, we believe that viral metagenomics applied in patients with high risk for acquiring parenterally transmitted infections can serve as a direct indicator for evaluation of transfusion safety.

Prediction of unfavorable outcomes in cryptococcal meningitis: results of the multicenter Infectious Diseases International Research Initiative (ID-IRI) cryptococcal meningitis study.

Cryptococcal meningitis (CM) is mostly seen in immunocompromised patients, particularly human immunodeficiency virus (HIV)-positive patients, but CM may also occur in apparently immunocompetent individuals. Outcome analyses have been performed in such patients but, due to the high prevalence of HIV infection worldwide, CM patients today may be admitted to hospitals with unknown HIV status, particularly in underdeveloped countries. The objective of this multicenter study was to analyze all types of CM cases in an aggregate cohort to disclose unfavorable outcomes. We retrospectively reviewed the hospitalized CM patients from 2000 to 2015 in 26 medical centers from 11 countries. Demographics, clinical, microbiological, radiological, therapeutic data, and outcomes were included. Death, neurological sequelae, or relapse were unfavorable outcomes. Seventy (43.8%) out of 160 study cases were identified as unfavorable and 104 (65%) were HIV infected. On multivariate analysis, the higher Glasgow Coma Scale (GCS) scores (p = 0.021), cerebrospinal fluid (CSF) leukocyte counts > 20 (p = 0.038), and higher CSF glucose levels (p = 0.048) were associated with favorable outcomes. On the other hand, malignancy (p = 0.026) was associated with poor outcomes. Although all CM patients require prompt and rational fungal management, those with significant risks for poor outcomes need to be closely monitored.

Ischaemic stroke in HIV-infected patients: a case-control study.

OBJECTIVES: The aim of the study was to provide insights into the contributions of HIV infection stage, antiretroviral therapy (ART) and vascular risk factors to the occurrence of ischaemic stroke in HIV-infected patients. METHODS: We performed a case-control study of HIV-infected patients followed in our clinic. We compared patients hospitalized between January 2006 and June 2014 with an ischaemic stroke or transient ischaemic attack to age- and gender-matched controls without stroke. RESULTS: Of 2146 patients followed in our clinic, we included 23 cases (20 men and three women; mean age 51.3 years) and 23 controls. Eighty-three per cent of cases had had a stroke and 17% a transient ischaemic attack. According to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification, small-vessel occlusion was the most frequent aetiology, followed by large-artery atherosclerosis and cardioembolism. Compared with controls, stroke was statistically significantly associated with diabetes, smoking and low concentrations of high-density lipoprotein (HDL) cholesterol. Illegal drug use, a low CD4 count and a high viral load were also associated with ischaemic cerebral events. There were no statistically significant differences between cases and controls in Centers for Disease Control and Prevention (CDC) HIV stage, CD4 count nadir and HIV infection time-to-event. No statistically significant differences were found concerning ART or treatment compliance. CONCLUSIONS: In our single centre study, we found associations of illegal drug use, HIV replication and some traditional vascular risk factors with the occurrence of ischaemic cerebral events. The paradigm of the care of HIV-infected patients is changing. Concomitant diseases in the ageing patient with HIV infection, including cerebrovascular disease, must also be addressed in view of their impacts on morbidity and mortality. Apart from controlling the HIV infection and immunosuppression with ART, vascular risk factors must also be addressed.