ABSTRACT Objective: Thymidine-dependent small-colony variants (TD-SCVs) of Staphylococcus aureus are being isolated with increasing frequency from patients with cystic fibrosis (CF). The aim of this study was to evaluate the relationship between TD-SCV isolation and pulmonary function in patients with CF, as well as to determine whether the emergence of TD-SCVs was associated with trimethoprim-sulfamethoxazole (TMP-SMX) use and with coinfection with other microorganisms. Methods: This was a retrospective case-control study including patients with CF who visited the Clinical Hospital Complex of the Federal University of Paraná, in Curitiba, Brazil, between 2013 and 2022. Demographic, clinical, and spirometric data, as well as information on TD-SCVs and other isolated microorganisms, were collected from the medical records of patients with CF and TD-SCVs (TD-SCV group; n = 32) and compared with those of a matched group of patients with CF without TD-SCVs (control group; n = 64). Results: Isolation of TD-SCVs was positively associated with TMP-SMX use (p = 0.009), hospitalization (p < 0.001), and impaired pulmonary function (p = 0.04). Conclusions: The use of TMP-SMX seems to contribute to the emergence of TD-SCVs, the isolation of which was directly associated with worse pulmonary function in our sample. Objective Thymidinedependent Thymidine dependent smallcolony small colony TDSCVs TD SCVs (TD-SCVs CF. . (CF) TDSCV SCV trimethoprimsulfamethoxazole trimethoprim sulfamethoxazole TMPSMX TMP SMX (TMP-SMX microorganisms Methods casecontrol case control Paraná Curitiba Brazil 201 2022 Demographic clinical data 32 64. 64 64) Results p 0.009, 0009 0.009 , 0 009 0.009) 0.001, 0001 0.001 001 0.001) 0.04. 004 0.04 04 0.04) Conclusions TDSCVs, SCVs, sample (CF 20 202 3 6 000 0.00 00 0.0 2 0.

RESUMO Este estudo avaliou as características funcionais da reação em cadeia da polimerase (PCR) multiplex para amostras de líquido cefalorraquidiano (LCR) de pacientes com características celulares e bioquímicas de meningite bacteriana aguda e culturas de LCR positivas ou negativas. Métodos: O PCR multiplex foi realizado em 36 amostras de LCR: meningite bacteriana aguda comprovada por cultura (n = 7), meningite bacteriana aguda com cultura negativa (n = 17), meningite linfocítica (n = 8) e LCR normal (n = 4). As características funcionais do PCR multiplex foram avaliadas para meningite bacteriana definitiva e provável, utilizando cultura positiva, características citológicas e bioquímicas do LCR como padrão-ouro. Resultados: O PCR multiplex do LCR foi eficiente no grupo com características celulares e bioquímicas do LCR de meningite bacteriana, mas com cultura do LCR negativa. Este grupo demonstrou especificidade, valor preditivo positivo e eficiência altos. Conclusões: Os autores concluíram que o PCR multiplex do LCR pode melhorar a velocidade e a precisão do diagnóstico de meningite bacteriana em um ambiente clínico como complemento aos ensaios imunológicos e bacteriológicos clássicos no LCR. Também é útil para meningite bacteriana aguda com cultura de LCR negativa.

ABSTRACT This study evaluated the operational characteristics of the multiplex polymerase chain reaction (PCR) for cerebrospinal fluid (CSF) from patients with cellular and biochemical characteristics of acute bacterial meningitis and positive or negative CSF cultures. Methods: Multiplex PCR was performed for 36 CSF samples: culture-proven acute bacterial meningitis (n = 7), culture-negative acute bacterial meningitis (n = 17), lymphocytic meningitis (n = 8), and normal CSF (n = 4). The operational characteristics of multiplex PCR were evaluated with definite and probable bacterial meningitis, using culture positive, cytological and biochemical CSF characteristics as the gold standard. Results: Multiplex PCR for CSF was efficient in the group with CSF cellular and biochemical characteristics of acute bacterial meningitis but with a negative CSF culture. This group demonstrated high specificity, positive predictive value, and efficiency. Conclusions: Multiplex PCR for CSF can improve the speed and accuracy of acute bacterial meningitis diagnosis in a clinical setting as a complement to classical immunological and bacteriological assays in CSF. It is also useful for CSF culture-negative acute bacterial meningitis.

Abstract INTRODUCTION. This study aimed to evaluate different methods for differentiation of species of coagulase-negative staphylococci (CoNS) that caused infections in hospitalized immunocompromised patients. METHODS. A total of 134 CoNS strains were characterized using four different methods. RESULTS. The results of matrix assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) analysis were in complete agreement with those of tuf gene sequencing (kappa index = 1.00). The kappa index of Vitek 2® Compact analysis was 0.85 (very good) and that of the conventional method was 0.63 (moderate). CONCLUSIONS . MALDI-TOF MS provided rapid and accurate results for the identification of CoNS (134; 100%).

Abstract Background: Carbapenem-resistant Acinetobacter baumannii infection is a concern in developing countries due to high incidence, few therapeutic options, and increasing costs. Objective: Characterize and analyze the antibiotic susceptibility patterns of carbapenem-resistant A. baumannii isolates and evaluate clinical data of meningitis and bacteremia caused by this microorganism. Methods: Twenty-six A. baumannii isolates from 23 patients were identified by MALDI-TOF and automated methods and genotyped using pulsed field genotyping electrophoresis. Clinical data and outcomes were evaluated. Susceptibility of isolates to colistin, tigecycline, meropenem, imipenem, and doxycycline was determined. Results: Mortality due to A. baumannii infections was 73.91%; all patients with meningitis and 7/8 patients with ventilator-associated pneumonia died. All isolates were susceptibility to polymyxin (100%; MIC50, MIC90: 1 µg/mL, 1 µg/mL) and colistin (100%; MIC50, MIC90: 2 µg/mL, 2 µg/mL), and 92% were susceptible to tigecycline (MIC50, MIC90: 1 µg/mL, 1 µg/mL) and doxycycline (MIC50, MIC90: 2 µg/mL, 2 µg/mL). bla OXA-23 was identified in 24 isolates. Molecular typing showed 8 different patterns: 13 isolates belonged to pattern A (50%). Conclusion: Carbapenem-resistant A. baumannii infections mortality is high. Alternative antimicrobial therapy (doxycycline) for selected patients with carbapenem-resistant A. baumannii infection should be considered.

Resumo Objetivo: Avaliar os fatores de risco associados ao óbito por infecção da corrente sanguínea causada pela Candida spp em pacientes pediátricos e avaliar a resistência ao principal antifúngico usado na prática clínica. Métodos: Este é um estudo transversal, observacional e analítico com coleta retrospectiva que incluiu 65 pacientes pediátricos internados com infecção da corrente sanguínea por Candida spp. Foi feita uma análise univariada para estimar a associação entre as características dos pacientes com candidemia e o óbito. Resultados: A incidência de candidemia foi de 0,23 casos em cada 1.000 pacientes/dia, com taxa de mortalidade de 32% (n = 21). O resultado clínico como sepse e choque séptico (p = 0,001), comorbidades como insuficiência renal aguda (p = 0,01) e riscos como ventilação mecânica (p = 0,02) e diálise (p = 0,03) estão associados ao aumento da mortalidade em pacientes pediátricos. As taxas de resistência e susceptibilidade dose-dependente contra o fluconazol foram de 4,2% e 2,1%, respectivamente. Não foi identificada resistência à anfotericina B e equinocandina. Conclusão: Os dados de nosso estudo sugerem que a sepse e o choque séptico, a insuficiência renal aguda e riscos como ventilação mecânica e diálise estão associados ao aumento da mortalidade em pacientes pediátricos. A mortalidade entre pacientes com candidemia é alta e não há diferença nas taxas de mortalidade entre as espécies. Sobre a resistência, é importante enfatizar a presença de baixa resistência nesta série.

Abstract Objective: To evaluate risk factors associated with death due to bloodstream infection caused by Candida spp. in pediatric patients and evaluate the resistance to the main anti-fungal used in clinical practice. Methods: This is a cross-sectional, observational, analytical study with retrospective collection that included 65 hospitalized pediatric patients with bloodstream infection by Candida spp. A univariate analysis was performed to estimate the association between the characteristics of the candidemia patients and death. Results: The incidence of candidemia was 0.23 cases per 1000 patients/day, with a mortality rate of 32% (n = 21). Clinical outcomes such as sepsis and septic shock (p = 0.001), comorbidities such as acute renal insufficiency (p = 0.01), and risks such as mechanical ventilation (p = 0.02) and dialysis (p = 0.03) are associated with increased mortality in pediatric patients. The resistance and dose-dependent susceptibility rates against fluconazole were 4.2% and 2.1%, respectively. No resistance to amphotericin B and echinocandin was identified. Conclusion: Data from this study suggest that sepsis and septic shock, acute renal insufficiency, and risks like mechanical ventilation and dialysis are associated with increased mortality in pediatric patients. The mortality among patients with candidemia is high, and there is no species difference in mortality rates. Regarding the resistance rates, it is important to emphasize the presence of low resistance in this series.

Abstract Setting Patients HIV+ attending in a reference clinic, Southern Brazil. Objective To compare the interferon-gamma-release assay (IGRA – QuantiFERON® TB Gold In-Tube) with the tuberculin skin test (TST – PPD-Rt 23) for latent tuberculosis infection (LTBI) in patients with HIV. Design Cohort study. Patients were simultaneously submitted to the TST and blood collection for the IGRA. Results A total of 140 subjects were included. Nine (6.4%) were IGRA+/TST+, 12 (8.6%) were IGRA+/TST−, 4 (3%) were IGRA−/TST+, and 115 (82%) IGRA−/TST−. There was poor agreement between tests (kappa = 0.2), and no correlation between these results and CD4+ T lymphocyte counts. During follow-up, one patient with negative results on both tests died from sepsis, and another with discordant results (IGRA+/TST−) exhibited TST seroconversion. Compared to the TST, IGRA showed a sensitivity and specificity of 69% and 90%, respectively. The IGRA detected 8% more positive results than the TST. All patients were followed up for 2 years. Conclusion The higher accuracy of the IGRA would result in LTBI treatments being administered to patients who would have otherwise been overlooked, decreasing the number of active tuberculosis cases. The long-term survival of HIV carriers requires further evaluation.

Cystic fibrosis (CF) patients with Burkholderia cepacia complex (Bcc) pulmonary infections have high morbidity and mortality. The aim of this study was to compare different methods for identification of Bcc species isolated from paediatric CF patients. Oropharyngeal swabs from children with CF were used to obtain isolates of Bcc samples to evaluate six different tests for strain identification. Conventional (CPT) and automatised (APT) phenotypic tests, polymerase chain reaction (PCR)-recA, restriction fragment length polymorphism-recA, recAsequencing, and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) were applied. Bacterial isolates were also tested for antimicrobial susceptibility. PCR-recA analysis showed that 36 out of the 54 isolates were Bcc. Kappa index data indicated almost perfect agreement between CPT and APT, CPT and PCR-recA, and APT and PCR-recA to identify Bcc, and MALDI-TOF and recAsequencing to identify Bcc species. The recAsequencing data and the MALDI-TOF data agreed in 97.2% of the isolates. Based on recA sequencing, the most common species identified were Burkholderia cenocepacia IIIA (33.4%),Burkholderia vietnamiensis (30.6%), B. cenocepaciaIIIB (27.8%), Burkholderia multivorans (5.5%), and B. cepacia (2.7%). MALDI-TOF proved to be a useful tool for identification of Bcc species obtained from CF patients, although it was not able to identify B. cenocepacia subtypes.

INTRODUCTION: Epidemiological data on the prevalence of extended-spectrum β-lactamases (ESBLs) are scarce in Brazil despite the fact that these data are essential for empirical treatment and control measures. The objective of this study was to evaluate the prevalence of different ESBLs by type and distribution in a tertiary hospital in southern Brazil. METHODS: We evaluated 1,827 enterobacterial isolates between August 2003 and March 2008 isolated from patients at a tertiary hospital. Samples were identified using a Vitek automated system and were confirmed by biochemical testing. The identified ESBL strains were characterized by phenotypic methods, polymerase chain reaction (PCR), and sequencing. Genetic similarities were evaluated by pulsed-field gel electrophoresis. RESULTS: It was 390 (21.3%) ESBL-producing strains, which expressed the ESBLs CTX-M (292), SHV (84), CTX and SHV (10), TEM (2), and PER (2). CONCLUSIONS: The prevalence of ESBL-expressing strains was high, especially in Klebsiella pneumoniae and Enterobacter spp. CTX-M was the predominant type of ESBL observed, and its genetic variability indicates a polyclonal distribution.

This study evaluated the clonal spread of carbapenem-resistant P. aeruginosa producing SPM-1 type metallo-β-lactamase (MBL), at the university hospital of Florianópolis, Santa Catarina, Brazil, compared to an epidemic clone previously reported, as well as strains collected in other three Brazilian states. Among the isolates, 17 (62%) were clonal and highly related to strains from other regions of Brazil. Six clonal strains harbored the blaSPM-1 gene. The finding of a unique SPM-1 producer clone suggests that its dissemination has contributed to the high resistance to carbapenems in Brazilian hospitals

INTRODUÇÃO: O isolamento de Pseudomonas aeruginosa resistente aos carbapenêmicos (PARC) tem sido cada vez mais frequente nos hospitais brasileiros. O presente estudo investigou a concentração inibitória mínina (CIM), a presença de metalo-β-lactamases (MβL), e uma possível relação clonal entre PARC isoladas entre junho de 2003 a junho de 2005, em um hospital escola na cidade de Florianópolis, Brasil. MÉTODOS: O estudo incluiu 29 PARC e sete isolados com suscetibilidade reduzida. A CIM foi determinada por diluição em ágar. A detecção de MβL foi realizada por sinergismo de duplo disco (SDD) e disco combinado (DC). Genes para MβL foram pesquisados por PCR e confirmados pela análise da sequência de nucleotídeos. A tipagem epidemiológica foi realizada por gel de eletroforese em campo pulsátil. RESULTADOS: Entre os 29 isolados resistentes aos carbapenêmicos, 100% apresentaram suscetibilidade a polimixina B, e 96,7% a piperacilina/tazobactam. Dezessete (62%) destes isolados pertenciam a um mesmo clone (clone A); entre estes, seis isolados apresentaram testes fenotípicos positivos para MβL e carreavam o gene blaSPM-1. O primeiro isolado PARC não foi relacionado ao clone A, carreava o gene blaIMP-16 e foi fenotipicamente positivo somente por DC. CONCLUSÕES: A propagação de um clone com alto nível de resistência sugere a transmissão cruzada como um importante mecanismo de disseminação e tem contribuído para o aumento nos níveis de resistência aos carbapenêmicos. Este estudo enfatiza a necessidade de vigilância contínua e melhoramento nas estratégias de controle de infecção nesta instituição.

INTRODUCTION: Carbapenem-resistant Pseudomonas aeruginosa (CRPA) has been isolated with increasing frequency in Brazilian hospitals. Since June 2003, its detection in a teaching hospital in the city of Florianópolis, Brazil, has increased. This study aimed to investigate the minimal inhibitory concentration (MIC), presence of Metallo-β-lactamase (MβL) and a possible clonal relationship among the isolates. METHODS: The study included 29 CRPA and seven isolates with reduced susceptibility. The MIC was determined by agar-dilution. Detection of MβL was performed by Double Disk Sinergism (DDS) and Combined Disk (CD). The MβL gene was verified by PCR and nucleotide sequence analysis. Epidemiological typing was performed by pulsed-field gel electrophoresis. RESULTS: Among the 29 carbapenem-resistant isolates, polymyxin B presented 100% susceptibility and piperacillin/tazobactam 96.7%. Seventeen (62%) strains were verified as clonal (A clone) and among these, six isolates indicated phenotypically positive tests for MβL and harbored the blaSPM-1 gene. The first CRPA isolates were unrelated to clone A, harbored blaIMP-16 and were phenotypically positive only by CD. CONCLUSIONS: The spread of a high-level of resistance clone suggests cross transmission as an important dissemination mechanism and has contributed to the increased rate of resistance to carbapenems. This study emphasizes the need for continuous surveillance and improved strategies.

Este estudo teve como objetivo avaliar as taxas de resistência de Streptococcus pneumoniae, isolados de pacientes com meningite, à penicilina G, ceftriaxona e vancomicina; avaliar possíveis fatores de risco para resistência antimicrobiana; descrever os sorotipos encontrados e sugerir a terapêutica empírica inicial para meningite. Foram isoladas 100 amostras de S. pneumoniae, encontrando-se 15% de resistência à penicilina, 1% à cefalosporina e 0% à vancomicina. Os sorotipos mais encontrados foram 14 (19%), 3 e 23F (10% cada). Analisando-se os resistentes, o sorotipo 14 (44%) também foi o mais freqüente. Os fatores de risco para resistência de S. pneumoniae encontrados foram: idade menor que um ano (p=0,01) e o uso prévio de antibiótico (p=0,046). As taxas de resistência encontradas, moderada a penicilina, baixa para cefalosporina e nula para vancomicina, sugerem como terapêutica empírica inicial para tratamento da meningite bacteriana aguda de origem comunitária, a cefalosporina de terceira geração isoladamente.

The main objectives of this study are to evaluate the resistance rates of Streptococcus pneumonia to penicillin G, ceftriaxone and vancomycin in patients with meningitis; to analyze possible risk factors to the antimicrobian resistance; to describe the serotypes detected and to suggest an initial empirical treatment for meningitis. The sensitiveness and serotypes of all isolated S. pneumoniae of patients with acute bacterial meningitis received by the Paraná State Central Laboratory from April 2001 to august 2002 have been evaluated. One hundred S. pneumoniae have been isolated, of which 15% were resistant to penicillin, 1% to cephalosporin and 0% to vancomycin. The serotypes most found were 14 (19%), 3 and 23F (10% each). When only the resistant serotypes were analyzed, the most prevalent was the 14 with 44%. The risk factors found in relation to the S. pneumoniae resistance were: age under one year old (p=0.01) and previous use of antibiotic (p=0.046). The resistance rates found, which were moderate to penicillin, low to cephalosporin and neutral to vancomycin, suggest the isolated use of a 3rd generation cephalosporin as an initial empirical therapy for the treatment of acute bacterial meningitis with a communitarian background.

Quinolones (nalidixic acid - NAL, norfloxacin - NOR, ciprofloxacin - CIP and gatifloxacin - GAT) were tested against Escherichia coli isolated from urine (385 patient samples) by disk diffusion (DD) and agar dilution (AD) methods. Fifty-three samples (13.8%) were classified as resistant to at least one of the quinolones tested. CIP and NOR susceptibilities were the same (91.4%) and they were similar to GAT (92.7%). Susceptibility to NAL, detected by the disk diffusion method, was used to predict susceptibility to NOR, CIP and GAT by the agar dilution method. The sensitivity and specificity of NAL were 100% and 95%, respectively. Twelve samples were analyzed for mutations in the quinolone resistance-determining region (QRDR) of the gyrA and parC genes. Sequencing of these genes failed to find any mutations in the quinolone-sensitive isolates. However, three mutations were observed in the isolates resistant to all the quinolones tested - two in gyrA and one in parC. A single mutation in gyrA was found in the strains that were resistant to nalidixic acid but fluoroquinolone-sensitive. These findings support the suggestion that NAL could be used as a marker for susceptibility to fluoroquinolones in routine microbiology laboratories. The overall resistance rate to quinolones in the present study was 13.8%, which is higher than that observed in other studies carried out in developed countries. Our findings serve as a warning that resistance to this group of antimicrobial agents is increasing.

Production of extended-spectrum beta-lactamases (ESBL) by enterobacteria is an important resistance mechanism against antimicrobial beta-lactamics. We tested 498 bacterial strains isolated from two tertiary-care teaching hospitals for ESBL production, using screening breakpoints for aztreonam and third generation cephalosporins, according to CLSI recommendations. Among these isolates, 155 were positive for the ESBL screening test, and 121 (78%) were confirmed by the clavulanic acid combination disk method. We found a high frequency of ESBL (24%) among Enterobacteriaceae, with a frequency of 57.4% for Klebsiella pneumoniae, 21.4% for Klebsiella oxytoca, and 7.2% for E. coli. In other members of Enterobacteriaceae, non-Klebsiella and non-E. coli, the prevalence was 21.6%. Ceftriaxone and cefotaxime showed a higher sensitivity in the screening test (99.2%) when compared to ceftazidime, aztreonam and cefpodoxime. However, cefotaxime/cefotaxime plus clavulanic acid showed a higher sensitivity in the confirmatory test (96.7%).

Isolation and identification of etiological agents found in body fluids can be of critical importance for the recovery of patients suffering from potentially-severe infections, which are often followed by serious sequels. Eighty-two samples of different body fluids were analyzed using two different methods: (1) the conventional culture method (agar plating) and (2) the enrichment culture technique, using the Bact/Alert® blood culture bottle. The number of positive cultures increased on average from 9.7% to 23.1% with the enrichment culture technique. Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus were the most frequently isolated bacteria. The enrichment method could provide a more accurate means the identifying etiological agents.