Rapid diagnostic of multidrug-resistant sepsis pathogens directly from blood culture bottles using MALDI-TOF and the EUCAST RAST.

In this study, rapid diagnostic of multidrug-resistant (MDR) sepsis pathogens, directly from positive blood culture (BC) bottles, was evaluated by combining MALDI-TOF and the EUCAST Rapid Antimicrobial Susceptibility Testing (RAST). Carbapenemase production in Escherichia coli and Klebsiella pneumoniae isolates was also evaluated by RAST. From 171 positive BC bottles analyzed, 79 (46 %) MDR species, including E. coli (4/34, 12 %), K. pneumoniae (33/48, 69 %), Pseudomonas aeruginosa (12/12, 100 %), Acinetobacter baumannii (15/15, 100 %), and Staphylococcus aureus (14/37, 38 %) displaying resistance to beta-lactams, fluoroquinolones, aminoglycosides, and/or trimethoprim/sulphamethoxazole, were identified. In this regard, turnaround time of direct MALDI-TOF identification and RAST was < 7 h, which was significantly (p< 0.05) lower than our routine method. Carbapenemase detection by RAST displayed 100% sensitivity and 88.7 % specificity at 8 h. This protocol could offer advantages for the treatment and clinical outcomes of septic patients, improving the rapid diagnostic of sepsis by MDR pathogens.

Respiratory Viral Shedding in Healthcare Workers Reinfected with SARS-CoV-2, Brazil, 2020.

We documented 4 cases of severe acute respiratory syndrome coronavirus 2 reinfection by non-variant of concern strains among healthcare workers in Campinas, Brazil. We isolated infectious particles from nasopharyngeal secretions during both infection episodes. Improved and continued protection measures are necessary to mitigate the risk for reinfection among healthcare workers.

Clinical outcomes and molecular characterization of drug-resistant tuberculosis in pre- and extensively drug-resistant disease based on line probe assays.

Multidrug-resistant tuberculosis (MDR-TB) represents a significant impact in transmission, outcome, and health costs. The World Health Organization recommends implementation of rapid diagnostic methods for multidrug-resistance detection. This study was performed to evaluate the frequency of pre- and extensively drug resistant tuberculosis (pre-XDR-TB and XDR-TB) among MDR-TB patients, the pattern of resistance mutations for fluoroquinolones and the clinical outcome. Adult patients followed at a Brazilian regional reference center for TB, from January 2013 to June 2019 were included. Stored Mycobacterium tuberculosis (Mtb) cultures were recovered, the DNA was extracted, and the susceptibility test was performed using the line probe assay for second line antimycobacterial drugs, Genotype MTBDRsl version 2.0 (Hain Lifescience, CmbH, Germany). Among 33 MDR-TB included patients, we diagnosed XDR-TB or pre-XDR in five (15%) cases. Of these, mutations related to fluoroquinolones resistance were observed in four Mtb isolates, including one who had no phenotypic resistance profile. In two other patients with phenotypic resistance to ofloxacin, genotypic resistance was not found. Case fatality rate was 60% in pre/XDR-TB group, compared to 3.6% in the remaining of patients. This study observed few cases of pre-XDR and XDR-TB among a MDR-TB cohort. Phenotypic and genotypic assays presented good agreement. Clinical outcome was more favorable for patients with susceptibility to fluoroquinolones and injectable drugs.

Nontuberculous mycobacterial infections in a Brazilian pediatric population: a seven-year survey.

The aim of this study was to describe the frequency of nontuberculous mycobacteria (NTM) isolation and their related outcomes among pediatric patients of a Brazilian university hospital from 2012 to 2019. NTM were identified in different clinical samples by microbiological culture and molecular-based methods. NTM were isolated from 14 patients, out of whom four (27%) were infected and were treated accordingly. Two were infected with Mycobacterium avium complex (MAC), two with M. abscessus complex (MABSC) and one with M. intracellulare. Two patients had cystic fibrosis-related lung disease and improved after successful NTM eradication. One patient was HIV-positive and died. One patient had severe combined immunodeficiency (SCID)-related pneumonia and is currently being followed-up. We conclude that NTM frequency in our center was low among pediatric patients. Whether this is inherent to Brazilian patients, due to the broad coverage of the Bacille Calmette-Guérin (BCG) vaccine in Brazil, or a result of underdiagnosis remains to be elucidated.

Prevalence and clinical outcomes of nontuberculous mycobacteria in a Brazilian cystic fibrosis reference center.

Nontuberculous mycobacteria (NTM) have been well established as an opportunistic pathogenic bacterial group for cystic fibrosis (CF) patients, with a prevalence ranging from 3% to 23% worldwide. A myriad of factors can bias the prevalence rate in different CF centers, especially misdiagnosis as systematic screening for NTM are still lacking in a number of centers. Here, we evaluated the presence and clinical outcomes of NTM isolation in microbiological respiratory cultures from CF patients attending a Brazilian reference center after setting up a systematic diagnostic protocol. Of 117 patients with respiratory samples cultured for NTM research, we found seven patients (6%) with at least one positive result for NTM [four males (57.1%), median age = 21 years (9-58)]. These cases are reported one-by-one. Median FEV1 was 40%, all patients showed signs of lung deterioration, with a median number of pulmonary exacerbations of three per patient/year. However, the impact of NTM isolation remains unclear in our center as all patients were coinfected with other CF respiratory pathogens. Our NTM prevalence assimilates to the lowest levels reported in literature, which is possibly influenced by the routinely applied Bacille Calmette-Guérin vaccine.

Haptoglobin polymorphism and diabetic nephropathy in Brazilian diabetic patients.

Diabetic nephropathy (DN) has an important impact on morbidity/mortality in diabetic patients. Genetic factors are probably involved in the development of this microvascular complication. Haptoglobin (Hp) is a genetically polymorphic glycoprotein that forms stable complexes with plasma-free hemoglobin (Hb) providing protection against heme-induced oxidative stress and kidney damage. The aim of the present study was to investigate the existence of association between the Hp genotypes and the presence of DN in Brazilian diabetic patients. The Hp genotypes of 265 patients, 95 type 1 diabetes mellitus (DM1) sufferers with at least 10 years of disease and 170 type 2 diabetes mellitus (DM2) sufferers with at least 5 years of disease were determined by allele-specific PCR; both groups included patients with and without DN. Hp allele and genotype frequencies were compared among the patient groups and between the patient groups and a control group of 142 healthy individuals. No association between Hp genotypes and DN could be demonstrated. Additionally, urinary albumin excretion values and the presence or absence of systemic arterial hypertension (SAH) were compared among the patient groups. Again, no significant correlations were found. The Hp polymorphism could not be associated with DN in the population studied here.