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Hemolytic disease of the fetus and newborn: systematic literature review of the antenatal landscape.BMC Pregnancy and Childbirth Jan 2023Prevention of pregnancy-related alloimmunization and the management of hemolytic disease of the fetus and newborn (HDFN) has significantly improved over the past...
BACKGROUND
Prevention of pregnancy-related alloimmunization and the management of hemolytic disease of the fetus and newborn (HDFN) has significantly improved over the past decades. Considering improvements in HDFN care, the objectives of this systematic literature review were to assess the prenatal treatment landscape and outcomes of Rh(D)- and K-mediated HDFN in mothers and fetuses, to identify the burden of disease, to identify evidence gaps in the literature, and to provide recommendations for future research.
METHODS
We performed a systematic search on MEDLINE, EMBASE and clinicaltrials.gov. Observational studies, trials, modelling studies, systematic reviews of cohort studies, and case reports and series of women and/or their fetus with HDFN caused by Rhesus (Rh)D or Kell alloimmunization. Extracted data included prevalence; treatment patterns; clinical outcomes; treatment efficacy; and mortality.
RESULTS
We identified 2,541 articles. After excluding 2,482 articles and adding 1 article from screening systematic reviews, 60 articles were selected. Most abstracted data were from case reports and case series. Prevalence was 0.047% and 0.006% for Rh(D)- and K-mediated HDFN, respectively. Most commonly reported antenatal treatment was intrauterine transfusion (IUT; median frequency [interquartile range]: 13.0% [7.2-66.0]). Average gestational age at first IUT ranged between 25 and 27 weeks. weeks. This timing is early and carries risks, which were observed in outcomes associated with IUTs. The rate of hydrops fetalis among pregnancies with Rh(D)-mediated HDFN treated with IUT was 14.8% (range, 0-50%) and 39.2% in K-mediated HDFN. Overall mean ± SD fetal mortality rate that was found to be 19.8%±29.4% across 19 studies. Mean gestational age at birth ranged between 34 and 36 weeks.
CONCLUSION
These findings corroborate the rareness of HDFN and frequently needed intrauterine transfusion with inherent risks, and most births occur at a late preterm gestational age. We identified several evidence gaps providing opportunities for future studies.
Topics: Female; Humans; Pregnancy; Erythroblastosis, Fetal; Hydrops Fetalis; Hemolysis; Blood Transfusion, Intrauterine; Fetus
PubMed: 36611144
DOI: 10.1186/s12884-022-05329-z -
JAMA Network Open Oct 2023Sickle cell disease (SCD) is a monogenic disorder, yet clinical outcomes are influenced by additional genetic factors. Despite decades of research, the genetics of SCD... (Meta-Analysis)
Meta-Analysis
IMPORTANCE
Sickle cell disease (SCD) is a monogenic disorder, yet clinical outcomes are influenced by additional genetic factors. Despite decades of research, the genetics of SCD remain poorly understood.
OBJECTIVE
To assess all reported genetic modifiers of SCD, evaluate the design of associated studies, and provide guidelines for future analyses according to modern genetic study recommendations.
DATA SOURCES
PubMed, Web of Science, and Scopus were searched through May 16, 2023, identifying 5290 publications.
STUDY SELECTION
At least 2 reviewers identified 571 original, peer-reviewed English-language publications reporting genetic modifiers of human SCD phenotypes, wherein the outcome was not treatment response, and the comparison was not between SCD subtypes or including healthy controls.
DATA EXTRACTION AND SYNTHESIS
Data relevant to all genetic modifiers of SCD were extracted, evaluated, and presented following STREGA and PRISMA guidelines. Weighted z score meta-analyses and pathway analyses were conducted.
MAIN OUTCOMES AND MEASURES
Outcomes were aggregated into 25 categories, grouped as acute complications, chronic conditions, hematologic parameters or biomarkers, and general or mixed measures of SCD severity.
RESULTS
The 571 included studies reported on 29 670 unique individuals (50% ≤ 18 years of age) from 43 countries. Of the 17 757 extracted results (4890 significant) in 1552 genes, 3675 results met the study criteria for meta-analysis: reported phenotype and genotype, association size and direction, variability measure, sample size, and statistical test. Only 173 results for 62 associations could be cross-study combined. The remaining associations could not be aggregated because they were only reported once or methods (eg, study design, reporting practice) and genotype or phenotype definitions were insufficiently harmonized. Gene variants regulating fetal hemoglobin and α-thalassemia (important markers for SCD severity) were frequently identified: 19 single-nucleotide variants in BCL11A, HBS1L-MYB, and HBG2 were significantly associated with fetal hemoglobin (absolute value of Z = 4.00 to 20.66; P = 8.63 × 10-95 to 6.19 × 10-5), and α-thalassemia deletions were significantly associated with increased hemoglobin level and reduced risk of albuminuria, abnormal transcranial Doppler velocity, and stroke (absolute value of Z = 3.43 to 5.16; P = 2.42 × 10-7 to 6.00 × 10-4). However, other associations remain unconfirmed. Pathway analyses of significant genes highlighted the importance of cellular adhesion, inflammation, oxidative and toxic stress, and blood vessel regulation in SCD (23 of the top 25 Gene Ontology pathways involve these processes) and suggested future research areas.
CONCLUSIONS AND RELEVANCE
The findings of this comprehensive systematic review and meta-analysis of all published genetic modifiers of SCD indicated that implementation of standardized phenotypes, statistical methods, and reporting practices should accelerate discovery and validation of genetic modifiers and development of clinically actionable genetic profiles.
Topics: Humans; Fetal Hemoglobin; alpha-Thalassemia; Anemia, Sickle Cell; Genotype; Genetic Variation
PubMed: 37851445
DOI: 10.1001/jamanetworkopen.2023.37484 -
American Journal of Obstetrics &... Sep 2023This study aimed to review the diagnostic criteria for mirror syndrome and describe its clinical presentation. (Review)
Review
OBJECTIVE
This study aimed to review the diagnostic criteria for mirror syndrome and describe its clinical presentation.
DATA SOURCES
Databases from PubMed, Scopus, Cochrane Library, ClinicalTrials.gov, and CINAHL were inquired for case series containing ≥2 cases of mirror syndrome from inception to February 2022.
STUDY ELIGIBILITY CRITERIA
Studies were included if they reported ≥2 cases of mirror syndrome and included case reports, case series, cohort studies, and case-control studies.
STUDY APPRAISAL AND SYNTHESIS METHODS
The studies' quality and risk of bias were independently assessed. Data were tabulated using Microsoft Excel and summarized using narrative review and descriptive statistics. This systematic review was conducted according to the Preferred Reporting Item for Systematic Reviews and Meta-Analyses statement. All eligible references were assessed. Screening of records and data extraction were independently performed, and a third author resolved disagreements.
RESULTS
Of 13 citations, 12 studies (n=82) reported diagnostic criteria for mirror syndrome: maternal edema (11/12), fetal hydrops (9/12), placental edema (6/12), placentomegaly (5/12), and preeclampsia (2/12); 12 studies (n=82) described the clinical presentation of mirror syndrome as maternal edema (62.2%), hypoalbuminemia (54.9%), anemia (39.0%), and new-onset hypertension (39.0%); 4 studies (n=36) reported that hemodilution was present in all patients; 8 studies (n=36) reported the etiology of fetal hydrops, with the most common being structural cardiac malformations (19.4%), alpha thalassemia (19.4%), Rh isoimmunization (13.9%), and nonimmune hydrops fetalis (13.9%); and 6 studies (n=47) reported maternal complications, 89.4% of which were major: postpartum hemorrhage (44.7%), hemorrhage requiring blood transfusion (19.1%), intensive care unit admission (12.8%), heart failure (10.6%), pulmonary edema (8.5%), and renal dysfunction (8.5%). In 39 cases, the reported fetal outcomes were stillbirth (66.6%) and neonatal or infant death (25.6%). The overall survival rate among continued pregnancies was 7.7%.
CONCLUSION
The diagnostic criteria of mirror syndrome differed considerably among studies. Mirror syndrome clinical presentation overlapped with preeclampsia. Only 4 studies discussed hemodilution. Significant maternal morbidity and fetal mortality were associated with mirror syndrome. Further research is warranted to elucidate the pathogenesis of mirror syndrome to better guide clinicians in identifying and managing the condition.
Topics: Female; Humans; Infant, Newborn; Pregnancy; Edema; Hydrops Fetalis; Placenta; Pre-Eclampsia; Syndrome; Systematic Reviews as Topic
PubMed: 37385374
DOI: 10.1016/j.ajogmf.2023.101067 -
Archives of Osteoporosis Nov 2021Multiple observational studies have reported high prevalence of fracture in patients with thalassemia. However, most of these studies have included limited number of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Multiple observational studies have reported high prevalence of fracture in patients with thalassemia. However, most of these studies have included limited number of patients, and only few of them have reported prevalence of fracture among patients with different types and severity of thalassemia.
OBJECTIVE
This systematic review and meta-analysis was conducted to summarize all available data of fracture prevalence among patients with thalassemia.
METHODS
A systematic review was conducted using EMBASE and MEDLINE databases from inception to June 2021 to determine studies that reported prevalence of fracture in thalassemia patients. The pooled prevalence with 95% confidence interval (95%CI) of fracture across studies was determined using a random-effect, generic inverse variance method.
RESULTS
After two rounds of systematic review, a total of 25 studies with 4934 patients were included in the meta-analysis. The pooled prevalence of fracture among patients with thalassemia was 16% (95%CI, 15-17%, I = 94.3%). The subgroup analyses showed that the pooled prevalence of fracture was 4% (95%CI, 2-6%; I = 70.4%) among patients with alpha thalassemia, 17% (95%CI, 16-19%; I = 93.2%) among patients with beta thalassemia, 18% (95%CI, 16-19%; I = 89.0%) among patients with transfusion-dependent thalassemia, and 7% (95%CI, 4-10%; I = 94.2%) among patients with non-transfusion-dependent thalassemia.
CONCLUSION
Fracture is common in patients with thalassemia, and may be more prevalent in beta thalassemia and transfusion-dependent thalassemia than in alpha thalassemia and non-transfusion-dependent thalassemia.
Topics: Fractures, Bone; Humans; Prevalence; Thalassemia; beta-Thalassemia
PubMed: 34773506
DOI: 10.1007/s11657-021-01026-0 -
Cureus Nov 2022β-thalassemia is characterized by the faulty generation of hemoglobin resulting in an elevated α/β globin ratio; this led to several patients needing red blood cell... (Review)
Review
β-thalassemia is characterized by the faulty generation of hemoglobin resulting in an elevated α/β globin ratio; this led to several patients needing red blood cell (RBC) transfusions for the rest of their lives. Luspatercept is an erythroid maturation test for treating various types of anemia, including β-thalassemia. It inhibits the Smad2/3 cascade and treats β-thalassemia by downregulating the transforming growth factor-beta (TGF-β) pathway. Luspatercept was evaluated in randomized controlled trials (RCTs). However, there is still limited data. Therefore, the study aims to review the current literature to assess the efficacy of luspatercept in cure β-thalassemia and its safety. From 2015 to 2022, searches were undertaken in PubMed, Google Scholar, and Cochrane. Only RCTs published in English were eligible for inclusion. The Cochrane Collaboration tool for bias assessment was used to analyze the quality of the publications. Our search strategy revealed 94 publications, of which 12 full-text papers were read and five were chosen for this review.All five trials included 1161 participants. Of whom, 153 (13.18%) entered phase 2, and 1008 (86.82%) entered phase 3. Two articles included 153 participants, of whom 70 (45.75%) were transfusion-dependent beta-thalassemia (TD) and 83 (54.25%) were non-transfusion-dependent beta-thalassemia (NTD) of phase 2. Three articles included 1008 participants, of whom 672 (66.67%) were given luspatercept and 336 (33.33%) were given a placebo. All participants in RCTs were 18 years of age or older. In phase 2, 0.2 to 1.25 mg/kg of luspatercept was given, and in phase 3, 1.0 to 1.25 mg/kg of luspatercept was given once every three weeks. In beta-thalassemia patients, luspatercept was more effective than a placebo and well tolerated. The high dose has shown promising results in the erythroid response, measured by a drop in blood transfusions or an average rise in hemoglobin levels. Luspatercept might make patients less likely to need RBC transfusions, improve their clinical results, and improve their quality of life. Adverse events were hyperuricemia, arthralgia, dizziness, influenza hypertension, and bone pain, but they were manageable.
PubMed: 36540460
DOI: 10.7759/cureus.31570 -
American Journal of Hematology Sep 2023This systematic literature review assessed the global prevalence and birth prevalence of clinically significant forms of alpha- and beta-thalassemia. Embase, MEDLINE,...
This systematic literature review assessed the global prevalence and birth prevalence of clinically significant forms of alpha- and beta-thalassemia. Embase, MEDLINE, and the Cochrane Library were searched for observational studies published January 1, 2000, to September 21, 2021. Of 2093 unique records identified, 69 studies reported across 70 publications met eligibility criteria, including 6 records identified from bibliography searches. Thalassemia prevalence estimates varied across countries and even within countries. Across 23 population-based studies reporting clinically significant alpha-thalassemia (e.g., hemoglobin H disease and hemoglobin Bart's hydrops fetalis) and/or beta-thalassemia (beta-thalassemia intermedia, major, and/or hemoglobin E/beta-thalassemia), prevalence estimates per 100 000 people ranged from 0.2 in Spain (over 2014-2017) to 27.2 in Greece (2010-2015) for combined beta- plus alpha-thalassemia; from 0.03 in Spain (2014-2017) to 4.5 in Malaysia (2007-2018) for alpha-thalassemia; and from 0.2 in Spain (2014-2017) to 35.7 to 49.6 in Iraq (2003-2018) for beta-thalassemia. Overall, the estimated prevalence of thalassemia followed the predicted pattern of being higher in the Middle East, Asia, and Mediterranean than in Europe or North America. However, population-based prevalence estimates were not found for many countries, and there was heterogeneity in case definitions, diagnostic methodology, type of thalassemia reported, and details on transfusion requirements. Limited population-based birth prevalence data were found. Twenty-seven studies reported thalassemia prevalence from non-population-based samples. Results from such studies likely do not have countrywide generalizability as they tended to be from highly specific groups. To fully understand the global prevalence of thalassemia, up-to-date, population-based epidemiological data are needed for many countries.
Topics: Pregnancy; Female; Humans; alpha-Thalassemia; beta-Thalassemia; Prenatal Diagnosis; Hydrops Fetalis; Asia; Hemoglobins, Abnormal
PubMed: 37357829
DOI: 10.1002/ajh.27006 -
The Journal of Maternal-fetal &... Oct 2022Mirror syndrome is a rare disease associated with high fetal mortality of up to 67.2%. It is thought to be underdiagnosed and is often associated with preeclampsia.... (Review)
Review
INTRODUCTION
Mirror syndrome is a rare disease associated with high fetal mortality of up to 67.2%. It is thought to be underdiagnosed and is often associated with preeclampsia. Mirror syndrome is characterized by "triple edema": generalized maternal, placental, and fetal edema.
OBJECTIVE
This comprehensive review aims to thoroughly summarize the existing data and provide a broad update on the topic to help accurate diagnosis and encourage further research.
METHODS
A comprehensive search of several databases (Ovid MEDLINE(R) and Epub Ahead of Print, In-Process & Other Non-Indexed Citations, and Daily, Ovid EMBASE, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus) was conducted.
RESULTS
The last systematic review of mirror syndrome cases was conducted in 2016 and included 113 patients. Much is still unknown about the pathophysiology of the disease and it remains underdiagnosed.
CONCLUSIONS AND RELEVANCE
Mirror syndrome is likely more prevalent than current data suggests for it is often misdiagnosed as pre-eclampsia. The differential of Mirror syndrome should be considered in anomalous presentations of pre-eclampsia as intervention may save the fetus and improve maternal symptoms. It is important to further the study on the pathophysiology of the disease to better understand, diagnose and potentially treat it, to avoid its high morbidity and mortality.
Topics: Edema; Female; Humans; Hydrops Fetalis; Placenta; Pre-Eclampsia; Pregnancy; Syndrome; Systematic Reviews as Topic
PubMed: 33722118
DOI: 10.1080/14767058.2020.1844656 -
Frontiers in Medicine 2022β-thalassemia is a disease caused by genetic mutations including a nucleotide change, small insertions or deletions in the β-globin gene, or in rare cases, gross...
β-thalassemia is a disease caused by genetic mutations including a nucleotide change, small insertions or deletions in the β-globin gene, or in rare cases, gross deletions into the β-globin gene. These mutations affect globin-chain subunits within the hemoglobin tetramer what induces an imbalance in the α/β-globin chain ratio, with an excess of free α-globin chains that triggers the most important pathogenic events of the disease: ineffective erythropoiesis, chronic anemia/chronic hypoxia, compensatory hemopoietic expansion and iron overload. Based on advances in our knowledge of the pathophysiology of β-thalassemia, in recent years, emerging therapies and clinical trials are being conducted and are classified into three major categories based on the different approach features of the underlying pathophysiology: correction of the α/β-globin disregulation; improving iron overload and reverse ineffective erythropoiesis. However, pathways such as the dysregulation of transcriptional factors, activation of the inflammasome, or approach to mechanisms of bone mineral loss, remain unexplored for future therapeutic targets. In this review, we update the main pathophysiological pathways involved in β-thalassemia, focusing on the development of new therapies directed at new therapeutic targets.
PubMed: 35492364
DOI: 10.3389/fmed.2022.880752 -
Clinical Genetics May 2023Non-immune hydrops fetalis (NIHF) has multiple genetic etiologies diagnosable by exome sequencing (ES). We evaluated the yield of prenatal ES for NIHF, and the... (Meta-Analysis)
Meta-Analysis Review
Non-immune hydrops fetalis (NIHF) has multiple genetic etiologies diagnosable by exome sequencing (ES). We evaluated the yield of prenatal ES for NIHF, and the contribution of additional clinical findings and history. Systematic review was performed with PROSPERO tag 232951 using CINAHL, PubMed, and Ovid MEDLINE from January 1, 2000 through December 1, 2021. Selected studies performed ES to augment standard prenatal diagnostic approaches. Cases meeting a strict NIHF phenotype were tabulated with structured data imputed from papers or requested from authors. Genetic variants and diagnostic outcomes were harmonized across studies using current ACMG and ClinGen variant classification guidelines. Thirty-one studies reporting 445 NIHF cases had a 37% (95% CI: 32%-41%) diagnostic rate. There was no significant difference between isolated NIHF and NIHF with fetal malformations or between recurrent and simplex cases. Diagnostic rate was higher for consanguineous than non-consanguineous cases. Disease categories included RASopathies (24%), neuromuscular (21%), metabolic (17%), lymphatic (13%), other syndromes (9%), cardiovascular (5%), hematologic (2%), skeletal (2%), and other categories (7%). Inheritance patterns included recessive (55%), dominant (41%), and X-linked (4%). ES should be considered in the diagnostic workup of NIHF with and without associated ultrasound findings regardless of history of recurrence or consanguinity.
Topics: Pregnancy; Female; Humans; Hydrops Fetalis; Exome Sequencing; Consanguinity
PubMed: 36757664
DOI: 10.1111/cge.14309 -
Molecular Genetics and Genomics : MGG Jan 2023The CRISPR/Cas9 technique is easily programmable, fast, more powerful, and efficient at generating a mutation compared to previous gene therapy methods. β-thalassemia... (Review)
Review
The CRISPR/Cas9 technique is easily programmable, fast, more powerful, and efficient at generating a mutation compared to previous gene therapy methods. β-thalassemia is the most common autosomal recessive disorder worldwide. Appropriate genomic changes in the β gene can be modified to alleviate the symptoms of the disease using the CRISPR/Cas9 system. PubMed/Medline, Scopus, Web of Science, and SID databases were searched in Persian and English from February 2000 to September 2022. Finally, 39 articles had inclusion criteria which were reviewed by two separate individuals. Among the reviewed articles, articles were divided into three categories. In the first group, studies attemped to increase the expression of γ-globin and production of hemoglobin F. The strategy of second group of studies were the reduction of the α-globin chain to prevent hemolysis of RBCs by accumulation of excessive α-globins. The third group corrected the mutations causing β-thalassemia. Studies have shown that the genome of β-thalassemia patients can be modified using the CRISPR/Cas9 technique, and this approach might be promising for the treatment of β-thalassemia.
Topics: Humans; CRISPR-Cas Systems; Gene Editing; beta-Thalassemia; Mutation
PubMed: 36403178
DOI: 10.1007/s00438-022-01978-z