Trends towards lower azole susceptibility among 200 Candida tropicalis bloodstream isolates from Brazilian medical centres.

OBJECTIVES: Candida tropicalis is one of the three most frequent species causing candidaemia in Latin America. Despite the high prevalence of C. tropicalis in candidaemia cases in Brazil, little is known about the trends in fluconazole susceptibility over time. The objective of this study was to evaluate temporal trends in azole resistance rates among C. tropicalis bloodstream isolates from patients treated in six Brazilian medical centres over a 12-year period. METHODS: We selected 200 C. tropicalis bloodstream isolates from six medical centres in Brazil collected between 2007 and 2018. Species identification was confirmed by MALDI-TOF/MS. Antifungal susceptibility testing for four antifungal agents was performed by the Clinical and Laboratory Standards Institute (CLSI) microbroth method. RESULTS: Overall, rates of non-susceptibility were 4% and 3.5% to fluconazole and voriconazole, respectively. All isolates were susceptible to amphotericin B and only one isolate was resistant to echinocandins. CONCLUSION: Although we failed to demonstrate statistical differences in the rates of azole resistance documented during the period of analysis, trends towards lower susceptibility to fluconazole and voriconazole were shown.

Erysipelas or cellulitis with a prosthetic joint in situ.

We describe a case of a 60-year old male who developed an acute prosthetic joint infection (PJI) of the knee, secondary to erysipelas of the lower leg due to beta-hemolytic Group G streptococci. As it is unknown how often this phenomenon occurs in patients with prosthetic implants and which patients are most prone to develop this complication, we analyzed: i) the incidence of the development of a PJI in these patients and ii) the clinical characteristics of streptococcal PJI during an episode of erysipelas/cellulitis. Based on a retrospective analysis of patients with a prosthetic implant in situ presenting at the emergency department with erysipelas/cellulitis, 1 out of 10 patients developed a PJI. An additional analysis within a multicenter cohort on streptococcal PJI demonstrated in 22 patients that a secondary PJI due to erysipelas/cellulitis mostly develops in young implants (<5 years old). In 20 cases (91%), the skin infection was in the same limb as the joint prosthesis suggesting contiguous spread of bacteria. These data emphasizes the importance of preventive measures to reduce the occurrence of skin infections in patients with prosthetic implants, and if an erysipelas or cellulitis does occur, to monitor patients carefully.

Staphylococcus aureus bloodstream infections in Latin America: results of a multinational prospective cohort study.

BACKGROUND: Substantial heterogeneity in the epidemiology and management of Staphylococcus aureus bacteraemia (SAB) occurs in Latin America. We conducted a prospective cohort study in 24 hospitals from nine Latin American countries. OBJECTIVES: To assess the clinical impact of SAB in Latin America. PATIENTS AND METHODS: We evaluated differences in the 30 day attributable mortality among patients with SAB due to MRSA compared with MSSA involving 84 days of follow-up. Adjusted relative risks were calculated using a generalized linear model. RESULTS: A total of 1030 patients were included. MRSA accounted for 44.7% of cases with a heterogeneous geographical distribution. MRSA infection was associated with higher 30 day attributable mortality [25% (78 of 312) versus 13.2% (48 of 363), adjusted RR: 1.94, 95% CI: 1.38-2.73, P < 0.001] compared with MSSA in the multivariable analysis based on investigators' assessment, but not in a per-protocol analysis [13% (35 of 270) versus 8.1% (28 of 347), adjusted RR: 1.10, 95% CI: 0.75-1.60, P = 0.616] or in a sensitivity analysis using 30 day all-cause mortality [36% (132 of 367) versus 27.8% (123 of 442), adjusted RR: 1.09, 95% CI: 0.96-1.23, P = 0.179]. MRSA infection was not associated with increased length of hospital stay. Only 49% of MSSA bloodstream infections (BSI) received treatment with ß-lactams, but appropriate definitive treatment was not associated with lower mortality (adjusted RR: 0.93, 95% CI: 0.70-1.23, P = 0.602). CONCLUSIONS: MRSA-BSIs in Latin America are not associated with higher 30 day mortality or longer length of stay compared with MSSA. Management of MSSA-BSIs was not optimal, but appropriate definitive therapy did not appear to influence mortality.

A Prospective Cohort Multicenter Study of Molecular Epidemiology and Phylogenomics of Staphylococcus aureus Bacteremia in Nine Latin American Countries.

Staphylococcus aureus is an important pathogen causing a spectrum of diseases ranging from mild skin and soft tissue infections to life-threatening conditions. Bloodstream infections are particularly important, and the treatment approach is complicated by the presence of methicillin-resistant S. aureus (MRSA) isolates. The emergence of new genetic lineages of MRSA has occurred in Latin America (LA) with the rise and dissemination of the community-associated USA300 Latin American variant (USA300-LV). Here, we prospectively characterized bloodstream MRSA recovered from selected hospitals in 9 Latin American countries. All isolates were typed by pulsed-field gel electrophoresis (PFGE) and subjected to antibiotic susceptibility testing. Whole-genome sequencing was performed on 96 MRSA representatives. MRSA represented 45% of all (1,185 S. aureus) isolates. The majority of MRSA isolates belonged to clonal cluster (CC) 5. In Colombia and Ecuador, most isolates (≥72%) belonged to the USA300-LV lineage (CC8). Phylogenetic reconstructions indicated that MRSA isolates from participating hospitals belonged to three major clades. Clade A grouped isolates with sequence type 5 (ST5), ST105, and ST1011 (mostly staphylococcal chromosomal cassette mec [SCCmec] I and II). Clade B included ST8, ST88, ST97, and ST72 strains (SCCmec IV, subtypes a, b, and c/E), and clade C grouped mostly Argentinian MRSA belonging to ST30. In summary, CC5 MRSA was prevalent in bloodstream infections in LA with the exception of Colombia and Ecuador, where USA300-LV is now the dominant lineage. Clonal replacement appears to be a common phenomenon, and continuous surveillance is crucial to identify changes in the molecular epidemiology of MRSA.

The Not-So-Good Prognosis of Streptococcal Periprosthetic Joint Infection Managed by Implant Retention: The Results of a Large Multicenter Study.

BACKGROUND.: Streptococci are not an infrequent cause of periprosthetic joint infection (PJI). Management by debridement, antibiotics, and implant retention (DAIR) is thought to produce a good prognosis, but little is known about the real likelihood of success. METHODS.: A retrospective, observational, multicenter, international study was performed during 2003-2012. Eligible patients had a streptococcal PJI that was managed with DAIR. The primary endpoint was failure, defined as death related to infection, relapse/persistence of infection, or the need for salvage therapy. RESULTS.: Overall, 462 cases were included (median age 72 years, 50% men). The most frequent species was Streptococcus agalactiae (34%), and 52% of all cases were hematogenous. Antibiotic treatment was primarily using ß-lactams, and 37% of patients received rifampin. Outcomes were evaluable in 444 patients: failure occurred in 187 (42.1%; 95% confidence interval, 37.5%-46.7%) after a median of 62 days from debridement; patients without failure were followed up for a median of 802 days. Independent predictors (hazard ratios) of failure were rheumatoid arthritis (2.36), late post-surgical infection (2.20), and bacteremia (1.69). Independent predictors of success were exchange of removable components (0.60), early use of rifampin (0.98 per day of treatment within the first 30 days), and long treatments (≥21 days) with ß-lactams, either as monotherapy (0.48) or in combination with rifampin (0.34). CONCLUSIONS.: This is the largest series to our knowledge of streptococcal PJI managed by DAIR, showing a worse prognosis than previously reported. The beneficial effects of exchanging the removable components and of ß-lactams are confirmed and maybe also a potential benefit from adding rifampin.

Evolution of methicillin-resistant Staphylococcus aureus clones in Latin America.

OBJECTIVES: Methicillin-resistant Staphylococcus aureus (MRSA) is a prominent nosocomial bacterial pathogen, associated with significant morbidity and mortality. The global incidence is increasing, and Latin America is no exception. This article reviews MRSA clonal distribution in Latin America and implications for clinical practice. DESIGN: A PubMed literature search (1966-2008) identified 32 articles that characterized MRSA clones in Latin America. RESULTS: Data from these articles show that since 1990, several epidemic MRSA clones have spread in Latin America. The multidrug-resistant Brazilian clone is widespread, especially in Brazil and Argentina, but more recently clones with susceptibility to a range of antibiotics have been detected in Brazil, whereas in Argentina, as in Chile, Colombia and Paraguay, the multidrug-resistant Cordobes/Chilean clone prevails. In Mexico, the New York/Japan clone is most frequent. Data were not available from every country and, despite the increasing prevalence of community MRSA infections, most were collected from tertiary care centers. CONCLUSIONS: A variety of epidemic MRSA clones are circulating in Latin America, some of which harbor genes that encode multidrug resistance or enhanced pathogenicity. Continued collection and reporting of epidemiological data is crucial for effective prevention and treatment.

Influenza virus vaccination in kidney transplant recipients: serum antibody response to different immunosuppressive drugs.

INTRODUCTION: This study prospectively accessed the immune response to the inactivated influenza vaccine in renal transplant recipients receiving either azathioprine or mycophenolate mofetil (MMF). Side effects were investigated. METHODS: Sixty-nine patients received one dose of inactivated trivalent influenza vaccine. Antihemagglutinin (HI) antibody response against each strain was measured before and one to six months after vaccination. RESULTS: Geometric mean HI antibody titers for H1N1 and H3N2 strains increased from 2.57 and 2.44 to 13.45 (p = 0.001) and 7.20 (p < 0.001), respectively. Pre- and post-vaccination protection rates for H1N1 and H3N2 increased from 8.7% to 49.3% (p < 0.001); and 36.3% (p < 0.001) and seroconversion rates were 36% and 25.3%, respectively. There was no response to influenza B. The use of MMF reduced the H1N1 and H3N2 protection rates and the seroconversion rate for the H1N1 strain when compared with the use of azathioprine, and subjects transplanted less than 87 months also had inferior antibody response. Adverse events were mild and there were no change on renal function post-vaccination. CONCLUSION: Renal transplant patients vaccinated against influenza responded with antibody production for influenza A virus strains, but not for influenza B. Use of MMF and shorter time from transplantation decreased the immune response to the vaccine.

Epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) in Latin America.

Methicillin-resistant Staphylococcus aureus (MRSA) has become a serious threat to public health worldwide. Ongoing surveillance is essential to support infection control committees and clinicians in the prevention and treatment of infection. However, in Latin America, resources for monitoring the changing epidemiology of MRSA remain limited. In this article, we review the current situation of MRSA in Latin America in order to highlight the need for a more harmonised effort to improve its management. Literature in the PubMed and SciELO databases as well as the website of the Pan American Health Organization were searched for articles and information about the epidemiology of MRSA in Latin America. MRSA is already the leading cause of nosocomial infection in the Latin American region, and the number of reports of community-acquired MRSA infections is also rising. However, the extent of the problem is not fully understood, especially since data tend to come from large hospitals whereas much of the population is served by small community healthcare centres that do not have extensive facilities for performing microbiological surveillance. In conclusion, wider-reaching and co-ordinated programmes to provide regular MRSA surveillance reports are required across the Latin American region.