No definitive prognostic biomarkers for carbon monoxide (CO) poisoning have been proposed. The aim of this study is to investigate, through a systematic literature review and pooled analysis, whether red blood cell distribution width (RDW) can predict disease severity in CO-poisoned patients. We performed an electronic search in Scopus and PubMed using the keywords: \'red blood cell distribution width\' OR \'RDW\' AND \'carbon monoxide\' AND \'poisoning,\' with no time or language restrictions (i.e. through August 2023) to find clinical studies that examined the value of RDW in patients with varying severity of CO poisoning. The analysis was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 reporting checklist. We identified 29 articles, seven of which were included in our analysis, with a total of 1979 CO-poisoned patients, 25.9% of whom were severely ill. In all but one of the studies, the RWD mean or median value was higher in CO-poisoned patients with severe disease. The weighted mean difference (WMD) of RDW was 0.36 (95% confidence interval (CI), 0.26-0.47)%. In the three articles in which the severity of illness in CO-poisoned patients was defined as cardiac injury, the WMD of the RDW was 1.26 (95%CI, 1.02-1.50)%. These results suggest that monitoring RDW in CO-poisoned patients may help to determine the severity of disease, particularly cardiac injury.

Diseases of the aorta, such as aortic aneurysm, dissection, and rupture, account for a large proportion of acute clinical emergencies. The red blood cell distribution width (RDW), which directly reflects anisocytosis (i.e., the heterogeneity of erythrocyte volumes), has emerged as a promising biomarker for many cardiovascular pathologies. Thus, we aimed to explore the implication of RDW in aortic pathologies. We searched Scopus and PubMed using the keywords \"RDW\" OR \"red blood cell distribution width\" AND \"aortic aneurysm\" OR \"aortic dilatation\" OR \"aortic dissection\" for identifying studies in which RDW values were measured in patients with these aortic diseases. Ten observational studies were finally included. In all studies, RDW value was increased in patients with aortic diseases. In the four studies in which sufficient RDW data were available for pooling, the weighted mean difference (WMD) of RDW in patients with or without complicated aortic pathologies was 0.575 (95 %CI, 0.254-0.896). RDW may be a valuable diagnostic and prognostic biomarker in patients with aortic pathologies.

The significant role of red blood cell distribution width (RDW) and D-Dimer as prognostic factors in patients with some blood malignancies has been reported recently.
We designed and performed a meta-analysis to investigate the prognostic roles of RDW and D-Dimer in subjects with diffuse large B-cell lymphoma (DLBCL).
We systematically reviewed PubMed-Medline, SCOPUS, EMBASE, Web of Science Core Collection, and Google Scholar up to the present to look for publications on prognostic effects of RDW and D-Dimer in DLBCL patients. For investigation of the associations between RDW and D-Dimer with the overall survival (OS) and progression-free survival (PFS) of the DLBCL cases, hazard ratio (HR) with 95% confidence intervals (CIs) was used.
We included 13 eligible studies in the present meta-analysis. The results of pooled analysis showed that increased levels of RDW was related to poor OS (HR = 2.01, 95% CI: 1.62-2.48, p value <.01, I2  = 0%) and poor PFS (HR = 1.52, 95% CI: 1.24-1.85, p value <.01, I2  = 16%) among the DLBCL patients. Similarly, a significant relationship was found between increased D-Dimer and poor OS (HR = 2.30, 95% CI: 1.03-5.14, p value <.05, I2  = 95%) of the DLBCL patients as well. In addition, there was no significant heterogeneity in OS (p value H = 0.65) and PFS (p value H = 0.31) related to RDW among studies included in the meta-analysis.
Our finding clearly confirmed that elevated RDW levels and D-Dimer were associated with adverse OS and PFS in DLBCL.

UNASSIGNED: Rheumatic diseases encompass a diverse group of autoimmune disorders that affect the joints and connective tissues. The red blood cell distribution width (RDW) has been widely investigated as an inflammatory marker. This scoping review aimed to explore the potential utility of RDW as an inexpensive marker for disease activity in patients with rheumatic diseases. By summarizing the available evidence, we aimed to determine whether RDW can serve as a reliable and accessible indicator of disease activity in these patients.
UNASSIGNED: A comprehensive search was systematically performed across electronic databases, encompassing PubMed, Embase, and Web of Science. Studies have explored the relationship between RDW and disease activity in rheumatic diseases. Data extraction focused on the study characteristics, methodologies, and findings related to RDW as a disease activity marker.
UNASSIGNED: After removing duplicates, the initial search yielded 25 relevant studies. These studies encompassed a variety of rheumatic diseases, with rheumatoid arthritis being the most frequently studied condition. The association between RDW and disease activity was assessed by using various disease activity indices and clinical parameters. While some studies have reported a significant correlation between elevated RDW and disease activity, others have yielded inconclusive results.
UNASSIGNED: From this review, we concluded that RDW is an inexpensive potential marker for the evaluation of disease activity in rheumatic diseases. RDW is promising as an inexpensive and readily available marker; however, its clinical utility in assessing disease activity in rheumatic conditions warrants more rigorous investigation through well-designed prospective studies.

Red blood cell distribution width (RDW) is a quantitative laboratory parameter applied for the measurement of anisocytosis and is a reliable and inexpensive method for clinical classification of anemia. An increased RDW reflects a great heterogeneity in the size of red blood cells typical of regenerative and iron-deficiency anemia. In humans, numerous and recent studies have shown a relationship between increased RDW and the risk of morbidity and mortality in patients with various disorders. In particular, a strong association has been established between changes in RDW and the risk of adverse outcome in humans with diseases affecting different organs or systems. Following the human literature, some studies have recently been conducted trying to clarify the clinical role of RDW in various animal disorders, particularly in dogs. In this review, we summarize and critically evaluate the results of the studies based on the measurement of RDW in dogs. We also emphasize the need for further and more extensive studies on the use of this simple and inexpensive parameter in animals.

Background: Despite great advances in medicine, numerous available laboratory markers, and radiological imaging, the diagnosis of acute appendicitis (AA) in some cases still remains controversial and challenging for clinicians. Because of that, clinicians are still looking for an ideal marker that would be specific to AA. The red blood cell distribution width (RDW) has been recently investigated in several studies as a potential biomarker for AA. The aim of this systematic review and meta-analysis was to systematically summarize and compare all relevant data on RDW as a diagnostic biomarker for AA. Methods: This systematic review and meta-analysis were performed as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Scientific databases (PubMed, Scopus, Web of Science, and Excerpta Medica database—EMBASE) were systematically searched for relevant comparative studies by two independent researches using keywords ((red cell distribution width) OR rdw) AND (appendicitis). An independent assessment of the methodological quality was performed by two authors using the Downs and Black scale. RevMan 5.4 software was used to perform the meta-analysis. Results: Fifteen studies were included in the final meta-analysis; the majority of the studies was retrospective. Nine studies compared the RDW values between AA and non-AA; four studies compared the same between AA and healthy controls, while two studies compared the RDW values among all three groups. The estimated heterogeneity among the studies for all outcome was statistically significant (I2 = 92−99%, p < 0.00001). The pooling the data demonstrated no statistically significant difference in the RDW values (weighted mean difference (WMD) = 0.03, 95% CI = (−0.46, 0.52), p = 0.91) between AA and healthy controls as well as between AA and non-AA cases (WMD = 0.23, 95%CI = (−0.19, 0.65), p = 0.28). A separate subanalysis was performed to evaluate the utility of this biomarker for the pediatric age group. Pooling the data demonstrated no significant difference among the AA and non-AA groups in terms of the RDW values (WMD = 0.99, 95% CI = (−0.35, 2.33), p = 0.15). Conclusion: The RDW value difference demonstrated no statistically significant difference in AA versus healthy individuals and AA versus non-AA individuals. At the moment, there is no evidence of RDW utility in diagnostic testing of AA. Further research with prospective, multicenter studies and studies targeting special patient groups with a large sample size are needed in this field.

Previous studies showed that red blood cell distribution width (RDW) can be used as a prognostic and diagnostic index in various non-hematological diseases, including severe infections and sepsis. Here, we provide a narrative review to summarize the findings of available studies investigating the relationship between RDW and sepsis. Current evidence suggests that increased RDW on admission, both in adults and neonates, may be associated with unfavorable outcomes on the short- and long-term. In patients with suspected sepsis, RDW has modest value for predicting positive blood culture. Accordingly, its diagnostic value for sepsis seems limited, whilts dynamic changes of RDW are associated with outcome of sepsis. Taken together, these results suggest that RDW could be used as a prognostic index in septic patients.

Anisocytosis has been associated with the severity and prognosis of several acute and chronic diseases, as well as physiological conditions such as pregnancy. Anisocytosis is quantified by the red blood cell distribution width (RDW), expressed as the ratio, multiplied by 100, between the standard deviation (SD) of red blood cell volumes and the mean corpuscular volume, or as the SD of erythrocyte volumes (RDW-SD). The aim of the present review was to report the state of the art on the physiological values and the putative diagnostic and prognostic roles of RDW in complicated pregnancy. Literature research for articles published in the last ten years was conducted in Pubmed, Web of Science, ClinicalTrials.gov, and Scopus databases. Abstracts were independently screened by two investigators. If relevant, full articles were retrieved. References, in these articles, citing relevant reviews or original studies were also accessed to identify additional eligible studies. Any disagreement between the reviewers was resolved by a third investigator. A total of 28 studies were included in the review. These studies reported changes in RDW values during physiological pregnancy, and associations between the RDW and several pregnancy complications including anaemia, preeclampsia, gestational diabetes, and recurrent miscarriage. This review provides background information for establishing physiological and pathological RDW values in pregnancy for diagnostic and prognostic use in clinical practice.

OBJECTIVE: The aim of this systematic review and meta-analysis was to investigate the relationship between the Red Cell Distribution Width (RDW) and prognosis in upper aerodigestive tract (UADT) cancer.
METHODS: PubMed (via the web), Embase, Scopus, and the Cochrane Library were searched. A systematic review and meta-analysis was done to generate the pooled hazard ratios (HR) for overall survival (OS), disease specific survival (DSS), and recurrence free survival (RFS).
RESULTS: Our analysis included the results of 4200 patients in 8 cohorts. The pooled data demonstrated that an elevated RDW was associated with significantly poorer OS (HR: 1.44, 95% CI: 1.13-1.83), RFS (HR: 1.43, 95%CI: 1.13-1.82). The DSS result had high heterogeneity and 95% CI was not pooled.
CONCLUSIONS: An elevated RDW may be an indicator of poor prognosis in UADT cancers in certain populations. Further research is needed to confirm this effect.