The Activin/Follistatin Axis Is Severely Deregulated in COVID-19 and Independently Associated With In-Hospital Mortality.

BACKGROUND: Activins are members of the transforming growth factor-ß superfamily implicated in the pathogenesis of several immunoinflammatory disorders. Based on our previous studies demonstrating that overexpression of activin-A in murine lung causes pathology sharing key features of coronavirus disease 2019 (COVID-19), we hypothesized that activins and their natural inhibitor follistatin might be particularly relevant to COVID-19 pathophysiology. METHODS: Activin-A, activin-B, and follistatin were retrospectively analyzed in 574 serum samples from 263 COVID-19 patients hospitalized in 3 independent centers, and compared with demographic, clinical, and laboratory parameters. Optimal scaling with ridge regression was used to screen variables and establish a prediction model. RESULT: The activin/follistatin axis was significantly deregulated during the course of COVID-19, correlated with severity and independently associated with mortality. FACT-CLINYCoD, a scoring system incorporating follistatin, activin-A, activin-B, C-reactive protein, lactate dehydrogenase, intensive care unit admission, neutrophil/lymphocyte ratio, age, comorbidities, and D-dimers, efficiently predicted fatal outcome (area under the curve [AUC], 0.951; 95% confidence interval, .919-.983; P <10-6). Two validation cohorts indicated similar AUC values. CONCLUSIONS: This study demonstrates a link between activin/follistatin axis and COVID-19 mortality and introduces FACT-CLINYCoD, a novel pathophysiology-based tool that allows dynamic prediction of disease outcome, supporting clinical decision making.

Impact of oseltamivir use on the reduction of complications in patients with influenza: a prospective study.

To evaluate the factors associated with oseltamivir prescription and to study the effectiveness of oseltamivir in reducing influenza-related complications. A prospective cohort study using the SOS Doctors (a network of physicians who perform house-call visits in Attica, Greece). Patients with confirmed or clinically suspected influenza were followed up to 14 days during the 2011-2012 influenza period. 410 patients with confirmed or suspected influenza were included. Healthy adults were mainly enrolled, with a median age of 44 years. Influenza diagnosis was mainly based on clinical criteria (65.8 % of patients). Oseltamivir was prescribed for 45.4 % of them. In a multivariate analysis, prescription of oseltamivir was associated with the attending physician (p < 0.001), positive influenza test (p < 0.001) and diabetes (p = 0.027). Data on complications were available for 351 patients, and 50 (15.8 %) of them reported at least one. Seven patients required hospitalization. Types of complications (pneumonia, bronchitis, etc.) were not significantly different between patients receiving and those not receiving oseltamivir. In the multivariate analysis, higher oseltamivir prescription rate was associated with fewer complications (p < 0.001). Bearing in mind the limitations of a non-randomized study, in a real-life setting, oseltamivir prescription and the rate of complications in patients with influenza were associated with the attending physician, underlying diseases and diagnostic tests. Overall, when the frequency of oseltamivir prescription increased, the influenza-related complications decreased.

Antibiotic treatment of infections due to carbapenem-resistant Enterobacteriaceae: systematic evaluation of the available evidence.

We sought to evaluate the effectiveness of the antibiotic treatment administered for infections caused by carbapenemase-producing Enterobacteriaceae. The PubMed and Scopus databases were systematically searched. Articles reporting the clinical outcomes of patients infected with carbapenemase-producing Enterobacteriaceae according to the antibiotic treatment administered were eligible. Twenty nonrandomized studies comprising 692 patients who received definitive treatment were included. Almost all studies reported on Klebsiella spp. In 8 studies, the majority of infections were bacteremia, while pneumonia and urinary tract infections were the most common infections in 12 studies. In 10 studies, the majority of patients were critically ill. There are methodological issues, including clinical heterogeneity, that preclude the synthesis of the available evidence using statistical analyses, including meta-analysis. From the descriptive point of view, among patients who received combination treatment, mortality was up to 50% for the tigecycline-gentamicin combination, up to 64% for tigecycline-colistin, and up to 67% for carbapenem-colistin. Among the monotherapy-treated patients, mortality was up to 57% for colistin and up to 80% for tigecycline. Certain regimens were administered to a small number of patients in certain studies. Three studies reporting on 194 critically ill patients with bacteremia showed individually significantly lower mortality in the combination arm than in the monotherapy arm. In the other studies, no significant difference in mortality was recorded between the compared groups. Combination antibiotic treatment may be considered the optimal option for severely ill patients with severe infections. However, well-designed randomized studies of specific patient populations are needed to further clarify this issue.

Options for treating carbapenem-resistant Enterobacteriaceae.

PURPOSE OF REVIEW: To address the therapeutic management of carbapenem-resistant Enterobacteriaceae on the basis of literature of the last 12 months. RECENT FINDINGS: Retrospective and prospective (nonrandomized noncontrolled) studies provide data regarding the management of infections due to carbapenem-resistant Enterobacteriaceae. The combination of a carbapenem with colistin or high-dose tigecycline or aminoglycoside or even triple carbapenem-containing combinations if the minimum inhibitory concentration (MIC) range of carbapenem (meropenem and imipenem) resistance is 8 mg/l or less seems to have an advantage over monotherapy with either colistin or tigecycline or fosfomycin. For Enterobacteriaceae with MIC for carbapenems over 8 mg/l, combination regimens involve colistin, tigecycline usually administered in a double dose than that suggested by its manufacturer, fosfomycin and aminoglycosides in various combinations. SUMMARY: Suggestions based on the limited literature cannot be made safely. Combination regimens involving carbapenems for Enterobacteriaceae with MICs 8 mg/l or less for carbapenems (in dual combination with colistin or high-dose tigecycline or aminoglycoside or even triple combinations) seem to confer some therapeutic advantage over monotherapy. For Enterobacteriaceae with higher than the above-mentioned MICs, a combination of two or even three antibiotics among colistin, high-dose tigecycline, aminoglycoside and fosfomycin seems to confer decreased mortality.

Current Therapeutic Approaches for Multidrug-Resistant and Extensively Drug-Resistant Acinetobacter baumannii Infections.

The treatment of Acinetobacter baumannii infections remains a challenge for physicians worldwide in the 21st century. The bacterium possesses a multitude of mechanisms to escape the human immune system. The consequences of A. baumannii infections on morbidity and mortality, as well on financial resources, remain dire. Furthermore, A. baumannii superinfections have also occurred during the COVID-19 pandemic. While prevention is important, the antibiotic armamentarium remains the most essential factor for the treatment of these infections. The main problem is the notorious resistance profile (including resistance to carbapenems and colistin) that this bacterium exhibits. While newer beta lactam/beta-lactamase inhibitors have entered clinical practice, with excellent results against various infections due to Enterobacteriaceae, their contribution against A. baumannii infections is almost absent. Hence, we have to resort to at least one of the following, sulbactam, polymyxins E or B, tigecycline or aminoglycosides, against multidrug-resistant (MDR) and extensively drug-resistant (XDR) A. baumannii infections. Furthermore, the notable addition of cefiderocol in the fight against A. baumannii infections represents a useful addition. We present herein the existing information from the last decade regarding therapeutic advances against MDR/XDR A. baumannii infections.

The prevalence of long COVID-19 syndrome in hospitalized patients with COVID-19 pneumonia.

Introduction: Long COVID affects millions of individuals worldwide with a wide range of persistent symptoms. Pathogenesis, prevalence and clinical approach of this syndrome remain not well characterized.The aim of the study is the estimation of prevalence of long-COVID and identification of possible risk factors. Patients and Methods: This is an observational prospective study including COVID-19 patients hospitalized at the Department of Infectious Diseases of the University General Hospital of Alexandroupolis (Greece). Eligible COVID-19 patients were interviewed and examined 6, 12 and 18 months after COVID-19 symptoms onset and hospital discharge in order to evaluate the prevalence and consequences of long-COVID symptoms. Results: A total number of 995 patients were included. The median age at discharge was 55 years and 53% of patients were retired. The majority was males (57%). Vaccination against SARS-CoV-2 was completed in 52% (n=517) COVID-19 patients. More than 40% of COVID-19 patients had at least one symptom at 18 months after hospitalization. Intravenous antiviral 0treatment with remdesivir and complete vaccination status were found to lead to lower rates of Long-COVID. Conclusions: More studies in larger patient cohorts are needed in order to identify the underlying biological mechanisms of long-COVID and create effective interventions for prevention and treatment.

Current diagnosis and management of infectious mononucleosis.

PURPOSE OF REVIEW: Infectious mononucleosis is a common, usually self-limited disease. However, infectious mononucleosis may present with severe manifestations. Complications may also occur. Consequently, diagnostic and treatment issues regarding infectious mononucleosis are of major importance. RECENT FINDINGS: In this review, we focus on the evaluation of articles providing diagnosis and treatment data for infectious mononucleosis, published during the past 2 years. Twelve studies, deriving from extended search in PubMed, were included. Nine studies provided diagnosis data. The evaluated diagnostic methods were real-time PCR (RT-PCR), IgM/IgG antibodies measured with different assays [measurement of Epstein-Barr virus viral load (EBV-VL) in peripheral blood, neutrophil/lymphocyte/monocyte counts, C-reactive protein values, and monospot test]. The sensitivities reported for RT-PCR were high. The available treatment data were scarce (three studies). Two of them suggested that antivirals (mainly acyclovir and valacyclovir) may have a role in the treatment of infectious mononucleosis with complications, whereas the remaining study presented novel potential therapeutic patents including 5-substituted uracyle, azacytosine derivatives, and peptides inhibiting EBV-mediated membrane fusion. SUMMARY: RT-PCR and measurement of EBV-VL may provide useful tools for the early diagnosis of infectious mononucleosis in cases with inconclusive serological results. Antiviral agents may provide a useful treatment option in patients with severe infectious mononucleosis.

The Antiviral Effect of Nirmatrelvir/Ritonavir during COVID-19 Pandemic Real-World Data.

INTRODUCTION: Vaccination against SARS-CoV-2 and the prevalence of Omicron variants have reduced the risk of the severe clinical progress of COVID-19. However, the risk of breakthrough infections has increased, and early administration of an effective antiviral treatment is significant in order to prevent the severe progression of COVID-19 in vulnerable patients with comorbidities. PATIENTS AND METHODS: Adults with confirmed SARS-CoV-2 infection were included in a matched-pair retrospective study based on age, gender, comorbidities and vaccination status. They were divided into two groups: group A (n = 200) consisted of outpatients at increased risk of severe clinical progress who were treated with nirmatrelvir/ritonavir and group B (n = 200) consisted of non-hospitalized patients who did not receive antiviral treatment. Demographic data, clinical outcome (death, intubation), days of hospitalization, time for recovery, adverse events and treatment compliance were reported. RESULTS: The median age (75.24 ± 13.12 years in the study group and 76.91 ± 14.02 years in the comparison group) and the proportion of males (59% vs. 60.5%, respectively) were similar between the two groups. A total of 6.5% of patients in group A and 10.5% in group B were unvaccinated against SARS-CoV-2. Three patients from group A (1.5%) and one hundred eleven (55.5%) from group B required hospitalization. The duration of hospitalization (3 days vs. 10 days in group B, p < 0.001) and the total time needed for recovery (5 days vs. 9 days, p < 0.001) was shorter in the study group. A rebound of SARS-CoV-2 infection within 8-12 days after diagnosis was documented in 6.5% of patients in group A and 8% of patients in group B. CONCLUSION: Oral treatment with nirmatrelvir/ritonavir in high-risk non-hospitalized patients was safe and effective in preventing the severe clinical progress of COVID-19 pneumonia. Early administration of antiviral agents in vulnerable outpatients combined with a full vaccination scheme is significant in order to avoid hospitalization and severe clinical outcomes.

The Impact of the COVID-19 Pandemic on Antimicrobial Resistance and Management of Bloodstream Infections.

INTRODUCTION: The pressure of the COVID-19 pandemic on healthcare systems led to limited roles of infectious diseases services, increased rates of irrational use of antimicrobials, and incidence of infections by multidrug-resistant microorganisms. The aim of the present study is to evaluate the incidence of antimicrobial resistance and the management of bloodstream infections before and during the COVID-19 pandemic at the University General Hospital of Alexandroupolis (Greece). MATERIALS AND METHODS: This is a retrospective study conducted from January 2018 to December 2022. Data were collected from the University Microbiology Laboratory per semester regarding the isolated strains of Gram-positive and -negative bacteria in blood cultures and respiratory samples in hospitalized patients in medical and surgical wards and in the intensive care unit (ICU). Additionally, bloodstream infections with requested infectious disease consultations were reported (n = 400), determining whether these were carried out via telephone contact or at the patient's bedside. Demographic data, comorbidities, focus of infection, antimicrobial regimen, duration of treatment, length of hospitalization, and clinical outcome were analyzed. RESULTS: A total of 4569 strains of Gram-positive and -negative bacteria were isolated. An increasing trend was reported compared to the pre-pandemic period in the incidence of resistant Gram-negative bacteria, particularly in ICUs. Prior antimicrobial use and the rate of hospital-acquired infections were increased significantly during the pandemic. In the pre-pandemic period 2018-2019, a total of 246 infectious disease consultations were carried out, while during the period 2020-2022, the number was 154, with the percentage of telephone consultations 15% and 76%, respectively. Detection of the source of infection and timely administration of appropriate antimicrobial agents were more frequently recorded before the pandemic, and 28-day mortality was significantly reduced in cases with bedside consultations. CONCLUSION: The empowering of infectious disease surveillance programs and committees, rational use of antimicrobials agents, and bedside infectious disease consultations are vital in order to reduce the impact of infections caused by multidrug-resistant strains.

Impact of antibiotic MIC on infection outcome in patients with susceptible Gram-negative bacteria: a systematic review and meta-analysis.

The objective of this study was to analyze the impact of MIC values within the susceptible range of antibiotics on the outcomes of patients with Gram-negative infections. The PubMed and Scopus electronic databases were searched. We identified 13 articles (1,469 patients) that studied the impact of antibiotic MICs on the outcomes of infections; ß-lactams were studied in 10 of them. Infections due to Salmonella enterica strains with high fluoroquinolone MICs were associated with more treatment failures than those due to strains with low MICs (relative risk [RR], 5.75; 95% confidence interval [CI], 1.77 to 18.71). Among non-Salmonella enterobacteriaceae, there was no difference in treatment failures depending on the MIC value (RR, 1.18; 95% CI, 0.71 to 1.97); however, a higher all-cause mortality was observed for patients infected with strains with high MICs (RR, 2.03; 95% CI, 1.05 to 3.92). More treatment failures were observed for patients infected with nonfermentative Gram-negative bacilli when strains had high MICs (RR, 5.54; 95% CI, 2.72 to 11.27). The mortality rate for patients with infections with Gram-negative nonfermentative bacilli with high MICs was also higher than for those with low MICs (RR, 2.39; 95% CI, 1.19 to 4.81). The limited available data suggest that there is an association between high MICs, within the susceptible range, and adverse outcomes for patients with Gram-negative infections.

Carbapenems versus alternative antibiotics for the treatment of bacteraemia due to Enterobacteriaceae producing extended-spectrum ß-lactamases: a systematic review and meta-analysis.

OBJECTIVES: To study the comparative mortality associated with carbapenems and alternative antibiotics for the treatment of patients with extended-spectrum ß-lactamase (ESBL)-positive Enterobacteriaceae bacteraemia. METHODS: We searched systematically PubMed and Scopus databases for studies providing data for mortality among patients treated with carbapenems, ß-lactam/ß-lactamase inhibitor combinations (BL/BLIs) or non-BL/BLIs (mainly cephalosporins and fluoroquinolones), preferably as monotherapy. Studies focusing on patients of all ages with community- and healthcare-associated bacteraemia were eligible. Data were pooled using the technique of meta-analysis. RESULTS: Twenty-one articles, studying 1584 patients, were included. Escherichia coli and Klebsiella pneumoniae were the most commonly studied bacteria. Delay in appropriate treatment up to 6 days was reported. Carbapenems were used mainly as definitive therapy. Carbapenems were associated with lower mortality than non- BL/BLIs for definitive [risk ratio (RR) 0.65, 95% CI 0.47-0.91] and empirical (RR 0.50, 95% CI 0.33-0.77) treatment. No statistically significant differences in mortality were found between carbapenems and BL/BLIs administered as definitive (RR 0.52, 95% 0.23-1.13) or empirical (RR 0.91, 95% CI 0.66-1.25) treatment. BL/BLIs were not associated with lower mortality than non-BL/BLIs administered either definitively (RR 1.59, 95% 0.83-3.06) or empirically (RR 0.82, 95% 0.48-1.41). Data regarding subgroups according to the setting, comorbidity and bacterial species could not be extracted. CONCLUSIONS: Based on data from non-randomized studies, carbapenems may be considered the treatment of choice for empirical treatment of patients with ESBL-producing Enterobacteriaceae bacteraemia. The role of BL/BLIs should be further evaluated for definitive treatment. Further research should focus on faster identification of ESBL-positive pathogens and potential differences in the treatment of each bacterial species.

Prognostic significance of phosphorylated STAT-1 expression in premenopausal and postmenopausal patients with invasive breast cancer.

AIMS: STAT-1 is the first member of the family of signal transducers and activators of transcription (STATs). In breast cancer experimental models, an apoptotic and antiproliferative effect has been demonstrated. Our aim was to study the role of phosphorylated STAT-1 (pSTAT-1) in invasive breast carcinoma and its prognostic significance in premenopausal and postmenopausal patients. METHODS AND RESULTS: Immunohistochemistry was performed in 165 patients in order to detect the expression of pSTAT-1 and its correlation with oestrogen receptor (ER), progesterone receptor (PR), caspase-3, and pAkt. pSTAT-1 was immunodetected in the cytoplasm of the malignant cells (11.6%). In premenopausal patients, cytoplasmic pSTAT-1 was positively correlated with stage (P = 0.014), ER (P = 0.008), caspase-3 (P = 0.029), and pAkt (P = 0.045). Univariate analysis showed that cytoplasmic pSTAT-1 was associated with poor overall survival (P = 0.042) and the phenotype of pSTAT-1/ER or PR coexpression with shorter disease-free survival (P = 0.012). In contrast, in postmenopausal patients, no association with clinicopathological parameters and survival was observed, except for the relationship of pSTAT-1/ER or PR coexpression with longer disease-free survival (P = 0.034). CONCLUSIONS: This is the first study examining the role of pSTAT-1 in premenopausal and postmenopausal women with invasive breast cancer. Our results suggest that pSTAT-1 is related to tumour progression in premenopausal patients through the advanced stage and worse survival.

Proposed amendments regarding the definitions of multidrug-resistant and extensively drug-resistant bacteria.

INTRODUCTION: It is fortunate that an international panel of experts proposed definitions for multidrug-resistant (MDR) and extensively drug-resistant (XDR) in the past. AREAS COVERED: In our opinion, these definitions need amendments in order to be semantically more accurate. EXPERT OPINION: We suggest for the MDR definition to add to 'MDR is defined as non-susceptibility to at least one agent in three or more antimicrobial categories' that this non-susceptibility is at most to the total number of all antimicrobial categories minus two, so that the definition reads: MDR is defined as non-susceptibility to at least one agent in three or more antimicrobial categories and up to (and including) the total number of all antimicrobial categories minus two. We suggest that the experts' definition of XDR as 'non-susceptibility to at least one agent in all but two or fewer antimicrobial categories (i.e. bacterial isolates remain susceptible to only one or two categories)' has to be modified regarding the content of the parenthesis to: (i.e. bacterial isolates remain susceptible to only one or two or even none antimicrobial category [in this latter setting bacterial isolates are resistant to at least one antimicrobial agent in all antimicrobial categories and concurrently there is at least one antimicrobial agent to which the isolate is susceptible to]).

ß-D-glucan assay for the diagnosis of invasive fungal infections: a meta-analysis.

We aimed to assess the accuracy of measuring serum or plasma (1→3)-ß-D-glucan (BDG) for the diagnosis of invasive fungal infections (IFIs) by means of a meta-analysis of relevant studies. We searched in bibliographic databases for relevant cohort or case-control studies. We primarily compared BDG between patients with proven or probable IFIs (excluding Pneumocystis jirovecii infections), according to the criteria of the European Organization for Research and Treatment of Cancer/Mycoses Study Group or similar criteria, and patients without IFIs (excluding healthy individuals as controls). A total of 2979 patients (594 with proven or probable IFIs), included in 16 studies, were analyzed. The pooled sensitivity of BDG was 76.8% (95% confidence interval [CI], 67.1%-84.3%), and the specificity was 85.3% (95% CI, 79.6%-89.7%). The area under the summary receiver operating characteristic curve was 0.89. Marked statistical heterogeneity was noted. BDG has good diagnostic accuracy for distinguishing proven or probable IFIs from no IFIs. It can be useful in clinical practice, if implemented in the proper setting and interpreted after consideration of its limitations.

Once versus multiple daily dosing of aminoglycosides for patients with febrile neutropenia: a systematic review and meta-analysis.

BACKGROUND: Once daily dosing (ODD) of aminoglycosides has become a standard of care for most patient populations. However, the use of ODD of aminoglycosides has not been clarified in febrile neutropenia. METHODS: We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) that compared the effectiveness and safety of ODD versus multiple daily dosing (MDD) of aminoglycosides in patients with febrile neutropenia. We searched the PubMed, Scopus, Cochrane Central Register of Trials and clinicaltrials.gov databases up to July 2010. RESULTS: A total of five and eight RCTs were included in the effectiveness and safety analyses, respectively. We observed a trend towards better effectiveness of the ODD regimen in the clinically evaluable population {five RCTs, 403 patient-episodes, risk ratio (RR)  = 1.18 [95% confidence interval (95% CI): 0.98, 1.42]}, but not in the microbiologically evaluable population [three RCTs, 119 patient-episodes, RR = 1.11 (95% CI: 0.84, 1.48)]. The occurrence of nephrotoxicity was similar between the two groups [seven RCTs, 1643 patient-episodes, RR = 0.74 (95% CI: 0.36, 1.50)], as was ototoxicity [six RCTs, 862 patient-episodes, RR = 1.05 (95% CI: 0.51, 2.19)]. There was no difference in mortality [four RCTs, 403 patient-episodes, RR = 0.77 (95% CI: 0.21, 2.78)]. CONCLUSIONS: Although the generalization of our findings may be restricted by the relatively small sample size and other methodological limitations of the included RCTs, ODD appears to be at least as effective and as safe as MDD in patients with febrile neutropenia. RCTs comparing ODD versus MDD in patients with bacteraemia and profound or prolonged neutropenia would be of additional value.

Resistance to polymyxins: Mechanisms, frequency and treatment options.

Polymyxins act by binding to lipid A moiety of the bacterial lipopolysaccharide and subsequently disintegrating the bacterial membranes. The most important mechanism of resistance includes modifications of the bacterial outer membrane structure, including lipopolysaccharide. Lipopolysaccharide modification is mostly mediated by PmrA/PmrB and PhoP/PhoQ two-component regulatory systems. These mechanisms exist with some differences in many gram-negative bacterial species. Resistance to polymyxins is generally less than 10%. In specific regions, such as the Mediterranean basin, Korea and Singapore, they tend to be higher. Heteroresistance to polymyxins is associated with exposure to polymyxins and especially suboptimal therapeutic dosage. Polymyxin combination regimens, tigecycline and fosfomycin may be useful options for the treatment of polymyxin-resistant gram-negative infections.

Impact of SARS-CoV-2 on pregnancy outcomes (Review).

The impact of the pandemic outbreak associated with coronavirus 2019 disease (COVID-19) on pregnant women is of interest to obstetricians and gynecologists due to the vulnerability of this target group. In pregnant women and their infants, an exceptional clinical management is warranted. Current epidemiological findings provide information regarding the effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on pregnant patients and potential adverse perinatal outcomes. Overall, these findings are a strong indication that an increased antenatal surveillance for pregnant patients infected with COVID-19 is warranted. The aim of the present narrative review was to summarize the data obtained to date regarding the health of women during pregnancy, as well as that of the fetus associated with the risk of severe infection due to COVID-19. The present review aimed to provide further insight into the effects of this pandemic on pregnancy, also providing the experience of the authors on this matter as an example.

Fosfomycin versus other antibiotics for the treatment of cystitis: a meta-analysis of randomized controlled trials.

BACKGROUND: Cystitis is a common infection. The alarmingly high resistance rates exhibited by contemporary uropathogens necessitate the re-evaluation of old antibiotics. OBJECTIVES: To evaluate the effectiveness and safety of fosfomycin compared with other antibiotics for the treatment of patients with cystitis. METHODS: We performed a meta-analysis of randomized controlled trials (RCTs), generated from searches performed in PubMed, Scopus and Cochrane CENTRAL, which involved patients with cystitis treated with fosfomycin versus other antibiotics. RESULTS: Twenty-seven trials (eight double-blind) were included. Sixteen of these 27 trials involved exclusively non-pregnant female patients, 3 involved adult mixed populations of older age, 5 involved pregnant patients and 3 involved paediatric patients. Regarding clinical success, no difference was found in the comprehensive analysis regarding all comparators combined [10 RCTs, 1657 patients, risk ratio (RR) = 1.00, 95% confidence interval (CI) = 0.98-1.03] in trials involving non-pregnant females and in trials involving mixed populations. Insufficient relevant data were provided from trials involving paediatric and pregnant patients. No difference between fosfomycin and comparators was also found in all comparisons regarding the remaining effectiveness outcomes (namely microbiological success/relapse/re-infection). Fosfomycin had a comparable safety profile with the evaluated comparators in non-pregnant women, mixed and paediatric populations, whereas it was associated with significantly fewer adverse events in pregnant women (4 RCTs, 507 patients, RR = 0.35, 95% CI = 0.12-0.97). CONCLUSIONS: In the era of high drug resistance rates, reported even among community-acquired uropathogens, fosfomycin may provide a valuable alternative option for the treatment of cystitis in non-pregnant and pregnant women and in elderly and paediatric patients.