An overview of systematic reviews on imaging tests for diagnosis of pulmonary embolism applying different network meta-analytic methods.

PURPOSE: This study aimed to apply different methods of diagnostic test accuracy network meta-analysis (DTA-NMA) for studies reporting results of five imaging tests for the diagnosis of suspected pulmonary embolism (PE): pulmonary angiography (PA), computed tomography angiography (CTPA), magnetic resonance angiography (MRA), planar ventilation/perfusion (V/Q) scintigraphy and single-photon emission computed tomography ventilation/perfusion (SPECT V/Q). METHODS: We searched four databases (MEDLINE [via PubMed], Cochrane CENTRAL, Scopus, and Epistemonikos) from inception until June 2, 2022 to identify systematic reviews (SRs) describing diagnostic accuracy of PA, CTPA, MRA, V/Q scan and SPECT V/Q for suspected PE. Study-level data were extracted and pooled using a hierarchical summary receiver operating characteristic (HSROC) meta-regression approach and two DTA-NMA models to compare accuracy estimates of different imaging tests. Risk of bias was assessed using the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies-2) tool and certainty of evidence using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) framework. RESULTS: We identified 13 SRs, synthesizing data from 33 primary studies and for four imaging tests (PA, CTPA, MRA and V/Q scan). The HSROC meta-regression model using PA as the reference standard showed that MRA had the best overall diagnostic performance with sensitivity of 0.93 (95% confidence interval [CI]: 0.76, 1.00) and specificity of 0.94 (95% CI: 0.84, 0.99). However, DTA-NMA models indicated that V/Q scan had the highest sensitivity, while CTPA was most specific. CONCLUSION: Selecting a different DTA-NMA method to assess multiple diagnostic tests can affect estimates of diagnostic accuracy. There is no established method, but the choice depends on the data and familiarity with Bayesian statistics.

Prognostic value of stress hyperglycemia ratio in patients with acute myocardial infarction: A systematic review with Bayesian and frequentist meta-analysis.

The present systematic review and meta-analysis aimed to investigate the prognostic value of stress hyperglycemia ratio (SHR) in patients with acute myocardial infarction (AMI). A total of 26 cohort studies, involving 87,974 patients, were analyzed. The frequentist meta-analysis showed that AMI patients with SHR in the upper quantile had a significantly higher hazard of major adverse cardiovascular and cerebrovascular events (MACCE, HR = 1.7; 95 % CI= [1.42, 2.03]; P < 0.001; I2 = 71 %; P <0.01), long-term (HR = 1.64; 95 % CI= [1.49, 1.8]; P < 0.001; I2 = 16 %; P = 0.29) and in-hospital all-cause mortality (OR = 3.87; 95 % CI= [2.98, 5.03]; P < 0.001; I2 = 54 %; P = 0.03) compared to those with lower SHR. Prespecified subgroup analyses revealed that these results were consistent irrespective of diabetes status (P = 0.32 and 0.73 for subgroup differences) and that SHR was a significant predictor of MACCE both in AMI with obstructive coronary arteries (HR = 1.57; 95 % CI= [1.34, 1.83]; P < 0.001; I2 = 66 %; P < 0.01) and MINOCA (HR = 2.57; 95 % CI= [1.86, 3.56]; P < 0.001; I2 = 0 %; P = 0.84). The Bayesian analyses with weakly prior assumptions yielded comparable results with the frequentist approach and provided strong evidence that higher SHR values were associated with significantly greater hazard of MACCE, short-term and long-term mortality. Further, prospective research is warranted to provide deeper insights into this newer index of stress hyperglycemia before its potential incorporation in clinical prediction scores.

Preoperative Assessment of Perianal Fistulas with Combined Magnetic Resonance and Tridimensional Endoanal Ultrasound: A Prospective Study.

BACKGROUND: we designed a prospective study of diagnostic accuracy that compared pelvic MRI and 3D-EAUS with pelvic MRI alone in the preoperative evaluation and postoperative outcomes of patients with perianal fistulas. METHODS: the sample size was 72 patients and this was divided into two imaging groups. MRI alone was performed on the first group. Both MRI and 3D-EAUS were performed in parallel on the second group. Surgical exploration took place after two weeks and was the standard reference. Park's classification, the presence of a concomitant abscess or a secondary tract, and the location of the internal opening were recorded. All patients were re-evaluated for complete fistula healing and fecal incontinence six months postoperatively. All of the collected data were subjected to statistical analysis. RESULTS: the MRI group included 36 patients with 42 fistulas. The MRI + 3D-EAUS group included 36 patients with 46 fistulas. The adjusted sensitivity and negative predictive value were 1.00 for most fistula types in the group that underwent combined imaging. The adjusted specificity improved for intersphincteric fistulas in the same group. The adjusted balanced accuracy improved for all fistula types except rectovaginal. The combination of imaging methods showed improved diagnostic accuracy only in the detection of a secondary tract. The healing rate at six months was 100%. Fecal incontinence at six months did not present a statistically significant difference between the two groups (Fisher's exact test p-value > 0.9). Patients with complex perianal fistulas had a statistically significant higher probability of undergoing a second surgery (x2 test p-value = 0.019). CONCLUSIONS: the combination of pelvic MRI and 3D-EAUS showed improved metrics of diagnostic accuracy and should be used in the preoperative evaluation of all patients with perianal fistulas, especially those with complex types.

Prognostic impact of secondary prevention medical therapy following myocardial infarction with non-obstructive coronary arteries: a Bayesian and frequentist meta-analysis.

Aims: Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a clinical entity with several causes and pathophysiologic mechanisms. Secondary prevention with medical therapy used in patients with obstructive coronary artery disease has unclear benefits in MINOCA patients. Methods and results: A literature search was conducted until 8 March 2022. Random-effect frequentist and hierarchical Bayesian meta-analyses were performed to assess the clinical impact of medical therapy [renin-angiotensin-aldosterone system (RAAS) inhibitors, statins, dual antiplatelet therapy (DAPT), ß-blockers] in MINOCA patients. Outcomes of interest were all-cause mortality and major adverse cardiovascular events (MACE). A total of 12 663 MINOCA patients among five observational studies were analysed. The mean follow-up ranged from 12 to 90 months across studies. In frequentist meta-analysis, statins and ß-blockers were associated with a lower risk of all-cause mortality [pooled adjusted hazard ratios (aHRs) 0.53 and 0.81, with 95% confidence intervals (CIs) (0.37-0.76) and (0.67-0.97), respectively]. Only RAAS inhibitors were associated with a lower risk of MACE [pooled aHR: 0.69, with 95% CI (0.53-0.90)]. Bayesian meta-analysis based on informative prior assumptions offered strong evidence only for the benefit of statins on decreasing the risk of all-cause death [Bayes factor (BF): 33.2] and moderate evidence for the benefit of RAAS inhibitors on decreasing the risk of MACE (BF: 9); assigning less informative prior distributions did not affect the results, yet it downgraded the level of evidence to anecdotal. Conclusion: In this meta-analysis, statins and RAAS inhibitors were consistently associated with a lower risk of all-cause mortality and MACE, respectively, in patients with MINOCA. Neutral prognostic evidence was demonstrated for ß-blockers and DAPT.

Systematic Review and Meta-Analysis of Cardiovascular Medications in Neonatal Hypotension.

Background: Comparative studies among the various cardiovascular medications used for the treatment of neonatal hypotension are lacking. Methods: This systematic review and pairwise meta-analysis of the anti-hypotensive treatments in preterm and term infants was conducted to evaluate efficacy and impact on outcome. Electronic databases were searched up to February 2021 for relevant articles. As an extension of the current approach for study selection, a machine learning technique was used. Only randomized controlled trials (RCTs) of inotropes, pressors, volume therapy, and corticosteroids were included. Response to treatment was the primary outcome while secondary outcomes included mortality and common morbidities. Results: Nineteen RCTs involving 758 preterm and term neonates were found, and 8 treatments were evaluated. Most studies involved subjects with early hypotension associated with prematurity. Pairwise meta-analysis among treatments showed that dopamine was more effective than dobutamine regarding the response to treatment (restoration of normotension or normalization of blood pressure) (7 trials, 286 neonates, odds ratio, 3.06 [95% CI = 1.06-8.87]; I2 = 49%, very low quality of the evidence per GRADE). Comparisons of other treatments were not significant. No differences were found among regimens regarding survival and other secondary outcomes. Conclusion: In this systematic review and pairwise meta-analysis, only the comparison of dopamine versus dobutamine provided evidence for efficacy of treatment and favored dopamine. No safe conclusions could be reached in regard to other treatments. Data regarding the management of arterial hypotension in conditions other than transition after birth in preterm newborns are sparse both in preterm and term infants.

Impact of the presence of median arcuate ligament on biliary complications after liver transplantation.

INTRODUCTION: The presence of median arcuate ligament (MAL) during orthotopic liver transplantation (OLT) may cause a significant reduction in the arterial hepatic flow. The aim of the present study is to investigate the impact of MAL on biliary complications in patients who underwent OLT. METHODS: We performed a retrospective case-control study among patients who underwent OLT in Geneva University Hospital between 2007 and 2017, depending on the presence or absence of MAL. The matching was performed according to age, gender, lab-MELD score at the time of OLT and type of donor (living or dead). The presence of MAL was assessed by an expert liver radiologist on the preoperative CT angiographic evaluation. RESULTS: The incidence of MAL was 6.1% (19 patients). Baseline characteristics were comparable between the two groups. No significant difference in biliary complications was found between patients with and without MAL (37% and 24%, respectively). No patient presented hepatic artery thrombosis. After logistic regression, in patients with MAL, the MAL release and gastroduodenal artery preservation compared to no treatment, showed an odds ratio for post-OLT biliary complications of 1.5 and 1.25, respectively. There was no difference in overall graft survival and in hazard for biliary complications between patients with and without MAL. CONCLUSION: In the present study, we did not find any difference in the prevalence of biliary and arterial complications between patients with and without MAL. The choice of MAL treatment did not influence in a significant way the overall outcome and development of complications. However, if, at the end of arterial reconstruction, the arterial flow is not adequately established, MAL needs to be treated with the least invasive technique.

Comparative efficacy and safety of oral P2Y12 inhibitors for patients with chronic kidney disease and acute coronary syndrome: a network meta-analysis.

BACKGROUND: Currently, there is a paucity of data concerning the safety and effectiveness of P2Y12 inhibitors in the acute coronary syndrome (ACS) with chronic kidney disease (CKD) population. The aim of this study is to compare the different oral P2Y12 inhibitors in terms of efficacy and safety, focusing exclusively on patients with CKD who were treated for ACS. METHODS: We systematically searched PubMed, CENTRAL, and Web of Science to identify studies that compared different oral P2Y12 inhibitors (clopidogrel, prasugrel, and ticagrelor) in patients with ACS with CKD. Efficacy outcomes included the major adverse cardiovascular events composite outcome and safety outcomes included major bleedings and major or minor bleedings combined. We performed a frequentist network meta-analysis. RESULTS: Twelve studies were included in the systematic review, 7 CKD subgroup analyses of RCTs (8878 patients) and 5 observational studies (20175 patients). After the exclusion of studies with conservative management, prasugrel resulted in significant primary endpoint reduction versus clopidogrel (HR 0.80 and 95% CI 0.64 - 0.99), while ticagrelor did not (HR 0.88 and 95% CI 0.73 - 1.06). Major bleedings did not differ between the interventions. Ticagrelor resulted in more major or minor bleedings than clopidogrel (HR 1.21 and 95% CI 1.06 - 1.38), whereas prasugrel did not (HR 1.12 and 95% CI 0.84 - 1.49). CONCLUSION: In patients with ACS with underlying CKD, who are intended to receive invasive management, there may be a significant reduction of the primary efficacy outcome with prasugrel as compared to clopidogrel but not with ticagrelor as compared to clopidogrel. There probably exists no difference among interventions in the major bleedings. Dedicated RCTs are needed to confirm these results.

Comparison of Postprandial Serum Triglyceride and Apolipoprotein B Concentrations between the Two Phases of Menstrual Cycle in Healthy Women.

BACKGROUND: Sex hormones influence lipoprotein metabolism; whether the hormonal fluctuation during normal menstrual cycle has impact on non-fasting lipids remains unclear. OBJECTIVE: To examine the differences in postprandial triglyceride, apolipoprotein B (ApoB) and nonhigh density lipoprotein cholesterol (non-HDL-C) concentrations using a standardized fat tolerance test during the 2 menstrual cycle phases. METHODS: We enrolled 25 healthy, menstruating women. Each of them underwent a fat tolerance test during the 2 phases of the menstrual cycle. Blood samples were collected at baseline and up to 6 h postprandially. Differences in serum triglycerides, ApoB and non-HDL-C between the 2 phases were assessed. The incremental area under the curve (iAUC) was calculated. Reproducibility of the measurements was tested using the intraclass correlation coefficient (ICC) and coefficient of variation (CV). RESULTS: Serum triglyceride concentrations increased postprandially in both phases and the values were higher during the follicular compared with the luteal phase; however, the overall triglyceride response expressed as iAUC [median value (interquartile range)] did not differ between the follicular and the luteal phase [54.0 (-26.5, 107.0) and 48.0 (6.0, 114.5) mg x h/dl, respectively, p=0.64]. Serum ApoB concentrations did not increase postprandially and the overall ApoB response was not different between the 2 phases. Non-HDL-C concentrations changed postprandially, but the overall response was not different between the 2 phases of the menstrual cycle. Reproducibility of the measurements was moderate: ICC 0.689-0.848 for triglycerides, 0.721-0.771 for ApoB, 0.457-0.867 for non-HDL-C, and %CV >8 for all parameters. CONCLUSION: Serum triglyceride levels were higher during the follicular compared with the luteal phase after standardized meal consumption, but the overall postprandial triglyceride response did not differ between the 2 phases. Postprandial ApoB and non-HDL-C serum concentrations were not affected by the menstrual cycle.

Infections Due to Multidrug-Resistant Bacteria in Oncological Patients: Insights from a Five-Year Epidemiological and Clinical Analysis.

Bacterial infections are frequent complications in cancer patients. Among them, those caused by multidrug-resistant (MDR) bacteria increase morbidity and mortality mainly because of limited therapeutic options. Current knowledge regarding MDR infections in patients with solid tumors is limited. We assessed the epidemiology and risk factors of increased mortality in these patients. In this retrospective five-year single cohort observational study, we included all oncological patients with MDR infections. Cancer-related parameters, comorbidities, prior use of antibiotics, previous surgical interventions and hospitalization, as well as the use of invasive procedures were investigated as potential risk factors causing adverse outcomes. Seventy-three patients with MDR infection were included: 37% with carbapenem-resistant Klebsiella pneumoniae, 24% with oxacillin-resistant Staphylococcus aureus (MRSA) and 21% with carbapenem-resistant Acinetobacter baumanni. Previous colonization with MDR bacteria was detected in 14% patients, while 20% of the patients presented MDR colonization or infection at ward admission. Mortality during the infection episode was 32%. Duration of hospitalization and CRP were statistically significant risk factors of mortality, whereas administration of guided antibiotics was a protective factor. Knowledge of local epidemiology of MDR bacteria can help physicians promptly identify cancer patients at risk of MDR infections and initiate timely effective empirical antibiotic treatment that can eventually improve the overall therapeutic management.

Patients with extra-adrenal malignancies and adrenal lesions have similar rates of subclinical hypercortisolism compared with patients with true adrenal incidentalomas.

OBJECTIVE: During follow-up in cancer patients, adrenal lesions are frequently found by computer tomography imaging. In these patients, the frequency of subclinical Cushing's syndrome (SCS) has not been fully explored. The aim of the present study was to investigate the presence of SCS in cancer patients with adrenal lesions in comparison to patients with true adrenal incidentalomas. DESIGN: We studied 95 patients with adrenal lesions: 57 patients (group A, 20 males and 37 females) had a history of extra-adrenal malignancy and adrenal lesions were discovered during staging of the primary cancer, and 38 patients (group B, 6 males and 32 females) had adrenal incidentalomas. The two groups had similar BMI. All patients had unenhanced HU < 10 in computed tomography to ensure low risk of adrenal metastatic disease. Patients' morning plasma cortisol levels and ACTH were measured. An overnight 1 mg dexamethasone suppression test (ODST) was performed in all participants; in case of abnormal results, 24-h urine cortisol and the low-dose dexamethasone suppression test were additionally conducted. The cutoffs of morning cortisol values used for ODST were 1.8 and 5 µg/dl. RESULTS: When the cutoff of 1.8 µg/dl for suppressed morning cortisol was used, 42.1% of group A and 39.5% of group B had abnormal results (p = 0.95). By using the threshold of 5 µg/dl after ODST, 5.3% of group A and 13.2% of group B did not have suppressed cortisol levels with the 1 mg ODST (p = 0.18). The main factors found to influence suppressed cortisol levels after ODST in both groups were BMI and size of the adrenal lesion. CONCLUSIONS: Patients with extra-adrenal malignancies and adrenal lesions had similar rates of subclinical hypercortisolemia compared to patients with true adrenal incidentalomas.

Reporting guidelines on how to write a complete and transparent abstract for overviews of systematic reviews of health care interventions.

OBJECTIVE: An overview of systematic reviews (OoSRs) is a study designed to offer a broad view of evidence from existing systematic reviews (SRs). The abstract is an important part of an OoSRs as it can determine whether reading the full text is of interest. The aim of this article is to offer guidelines to promote transparent and sufficient reporting in abstracts of OoSRs of health care interventions. STUDY DESIGN AND SETTING: The items were developed by combining key features from abstracts of OoSRs, PRISMA for abstracts, and our published reporting guidelines for OoSRs. The initial version was distributed to experts to give feedback; pilot testing by a group of researchers followed. The refined checklist was applied by two reviewers independently in a sample of 40 abstracts. RESULTS: The developed instrument "Preferred Reporting Items for OoSRs abstracts" (PRIO for abstracts) consists of six sections with 15 topics including 20 items in total. The mean inter-rater reliability was 0.87 (95% confidence interval: 0.82, 0.92). An explanation and at least one published example of good reporting per item are provided. CONCLUSION: This instrument will assist authors in writing transparent and informative abstracts for OoSRs and can be adopted by journals that publish OoSRs.

Hepatitis B virus reactivation in HBsAg-negative, anti-HBc-positive patients receiving immunosuppressive therapy: a systematic review.

BACKGROUND: The optimal management of HBsAg-negative, anti-HBc-positive patients who receive immunosuppression remains unclarified. We systematically reviewed the available data on potential predictors of the risk of hepatitis B virus (HBV) reactivation in such patients. METHODS: A literature search identified 55 studies with 3640 HBsAg-negative, anti-HBc-positive patients who received immunosuppressive regimens. RESULTS: HBV reactivation was reported in 236 (6.5%) patients. The pooled HBV reactivation rates did not differ between patients with detectable or undetectable HBV DNA in studies with hematological diseases or regimens containing rituximab, but it was higher in patients with detectable than in those with undetectable HBV DNA who were taking rituximab-free regimens (14% vs. 2.6%; risk ratio [RR] 12.67, 95% CI: 95%CI 2.39-67.04, P=0.003) or had non-hematological diseases, although the latter was not confirmed by sensitivity analysis (RR 8.80, 95%CI 0.71-109.00, P=0.09). The pooled HBV reactivation rates were lower in patients with positive than in those with negative anti-HBs in studies with hematological (7.1% vs. 21.8%; RR 0.29, 95%CI 0.19-0.46, P<0.001) or non-hematological (2.5% vs. 10.7%; RR 0.28, 95%CI 0.11-0.76, P=0.012) diseases, and rituximab-containing (6.6% vs. 19.8%; RR 0.32, 95%CI 0.15-0.69, P=0.003) or rituximab-free (3.3% vs. 9.2%; RR 0.36, 95%CI 0.14-0.96, P=0.042) regimens. CONCLUSIONS: The risk of HBV reactivation is high; therefore, anti-HBV prophylaxis should be recommended in HBsAg-negative, anti-HBc-positive patients with hematological diseases and/or rituximab-containing regimens, regardless of HBV DNA and anti-HBs status. In contrast, patients with non-hematological diseases or rituximab-free regimens have a low risk of HBV reactivation and may not require anti-HBV prophylaxis if they have undetectable HBV DNA and positive anti-HBs.

Left Brachiocephalic Vein Stenosis due to the Insertion of a Temporal Right Subclavian Hemodialysis Catheter.

Central vein stenosis/occlusion is a common well-described sequel to the placement of hemodialysis catheters in the central venous system. The precise mechanisms by which central vein stenosis occurs are not well known. Current concepts in central vein stenosis pathophysiology focus on the response to vessel injury model, emphasizing the process of trauma. A case of left brachiocephalic vein stenosis due to the insertion and function of a temporary right subclavian hemodialysis catheter is presented. The purpose of the manuscript is to emphasize that, with the introduction of a temporary subclavian hemodialysis catheter via the right subclavian vein apart from causing concurrent stenosis/infarction of the right subclavian and right brachiocephalic vein, it is also possible to cause stenosis of the left brachiocephalic vein (close to its contribution to the superior vena cava) although the catheter tip is placed in the correct anatomical position in the superior vena cava.

Cumulative Evidence of Randomized Controlled and Observational Studies on Catheter-Related Infection Risk of Central Venous Catheter Insertion Site in ICU Patients: A Pairwise and Network Meta-Analysis.

BACKGROUND: Selection of central venous catheter insertion site in ICU patients could help reduce catheter-related infections. Although subclavian was considered the most appropriate site, its preferential use in ICU patients is not generalized and questioned by contradicted meta-analysis results. In addition, conflicting data exist on alternative site selection whenever subclavian is contraindicated. OBJECTIVE: To compare catheter-related bloodstream infection and colonization risk between the three sites (subclavian, internal jugular, and femoral) in adult ICU patients. DATA SOURCE: We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled trials, CINAHL, and ClinicalTrials.gov. STUDY SELECTION: Eligible studies were randomized controlled trials and observational ones. DATA EXTRACTION: Extracted data were analyzed by pairwise and network meta-analysis. DATA SYNTHESIS: Twenty studies were included; 11 were observational, seven were randomized controlled trials for other outcomes, and two were randomized controlled trials for sites. We evaluated 18,554 central venous catheters: 9,331 from observational studies, 5,482 from randomized controlled trials for other outcomes, and 3,741 from randomized controlled trials for sites. Colonization risk was higher for internal jugular (relative risk, 2.25 [95% CI, 1.84-2.75]; I = 0%) and femoral (relative risk, 2.92 [95% CI, 2.11-4.04]; I = 24%), compared with subclavian. Catheter-related bloodstream infection risk was comparable for internal jugular and subclavian, higher for femoral than subclavian (relative risk, 2.44 [95% CI, 1.25-4.75]; I = 61%), and lower for internal jugular than femoral (relative risk, 0.55 [95% CI, 0.34-0.89]; I = 61%). When observational studies that did not control for baseline characteristics were excluded, catheter-related bloodstream infection risk was comparable between the sites. CONCLUSIONS: In ICU patients, internal jugular and subclavian may, similarly, decrease catheter-related bloodstream infection risk, when compared with femoral. Subclavian could be suggested as the most appropriate site, whenever colonization risk is considered and not, otherwise, contraindicated. Current evidence on catheter-related bloodstream infection femoral risk, compared with the other sites, is inconclusive.

Efficacy and safety of linezolid for the treatment of infections in children: a meta-analysis.

UNLABELLED: Linezolid is an oxazolidinone antibacterial agent, with activity against Gram-positive bacteria. This study aimed to evaluate the efficacy and safety of linezolid in children with infections caused by Gram-positive pathogens. A systematic search was conducted by two independent reviewers to identify published studies up to September 2013. The accumulated relevant literature was subsequently systematically reviewed, and a meta-analysis was conducted. Eligible studies were randomized controlled trials assessing the clinical efficacy and safety of linezolid in children versus other antimicrobial agents for infections caused by Gram-positive bacteria. The primary outcome was treatment success in patients who received at least one dose of study drug, had clinical evidence of disease, and had complete follow-up. Meta-analysis was conducted with random effects models because of heterogeneity across the trials. Two randomized controlled trials (RCTs), involving 815 patients, were included. Linezolid was slightly more effective than control antibiotic agents, but the difference was not statistically significant [odds ratio (OR) = 1.39, 95 % confidence interval (CI) 0.98-1.98]. Treatment with linezolid was not associated with more adverse effects in general (OR = 0.61, 95 % CI 0.25-1.48). Eradication efficiency did not differ between linezolid and control regimens, but the sample size for these comparisons was small. CONCLUSION: The use of linezolid cannot be steadily supported from the results of the current meta-analysis. It appears to be slightly more effective than control antibiotic agents, but the difference was not significant, and the serious limitations present in this study restrict its use. Further studies providing evidence for clinical and microbiological efficacy of linezolid will support its use.