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Matar, Reem

https://orcid.org/0000-0002-8853-8408

Mayo Clinic

Mayo Clinic

Citations 20

Immune checkpoint inhibitor-associated lymphocytic colitis in a patient with metastatic melanoma
Matar, Reem , Zeinah, Khalid Abu, Modi, Tanish , DUCHARME-SMITH, ALLISON, Abu Zeinah, Khalid, Matar, Reem

BMJ Case Reports | May 19, 2026 | Volume: 19 | Issue: 5 | Pages: e270566

10.1136/bcr-2025-270566 Get It

We describe the case of a man in his 60s with metastatic melanoma on encorafenib/binimetinib and nivolumab/relatlimab, with a history of immune checkpoint inhibitor (ICI)-induced acute interstitial nephritis, who presented with acute-onset nausea, vomiting and profuse watery diarrhoea. Investigations excluded infectious causes, and flexible sigmoidoscopy with biopsy demonstrated lymphocytic colitis. His symptoms persisted despite discontinuation of Braftovi-Mektovi (BRAF–MEK) therapy and required escalation of corticosteroid therapy and budesonide initiation. This case highlights the diagnostic challenges of differentiating ICI-mediated colitis from adverse events of targeted therapy and underscores the importance of endoscopic and histological confirmation in guiding treatment.
Recurrent bowel angioedema in a patient with C1 esterase inhibitor deficiency
Matar, Reem , Volcheck, Gerald W., Matar, Reem , Volcheck, Gerald, Matar, Reem

BMJ Case Reports | March 19, 2026 | Volume: 19 | Issue: 3 | Pages: e268717

10.1136/bcr-2025-268717 Get It

Recurrent bowel obstruction secondary to angioedema is uncommon, particularly when due to C1 esterase inhibitor (C1-INH) deficiency. We present a case of a 56 year old, male patient with recurrent abdominal pain, nausea and vomiting secondary to bowel angioedema resulting in multiple hospitalisations and surgical interventions. This case underscores the importance of considering hereditary and acquired C1-INH deficiency in the differential diagnosis of recurrent abdominal pain and bowel oedema despite late onset and lack of concomitant facial or peripheral angioedema. We review the clinical presentation, laboratory evaluation and management of C1-INH deficiency, including the hereditary and acquired forms.
Cardiac Resynchronization Therapy, Remodeling, and Outcome in Patients With Amyloid Transthyretin Cardiomyopathy
Aimo, Alberto , Nesti, Martina , Vergaro, Giuseppe , Killu, Ammar M. , Bampatsias, Dimitrios, Tomasoni, Daniela , Forleo, Cinzia , Musca, Francesco , Rosenthal, Julie , Teruya, Sergio , Tameze, Mariel S., Nicolai, Alessio, Saro, Riccardo , Fico, Vera , Frau, Elisa, Longhi, Simone , Chimenti, Cristina , Metra, Marco , Grogan, Martha , Perfetto, Federico , Merlo, Marco , Maurer, Mathew S. , Masri, Ahmad , Rosenthal, Julie L , Teruya, Sergio L , Al Shakarchi, Nader , Castiglione, Vincenzo , Porcari, Aldostefano , Fico, Vera , Guaricci, Andrea I , Tini, Giacomo , Cipriani, Alberto , Longhi, Simone , Chimenti, Cristina , Metra, Marco , Grogan, Martha , Perfetto, Federico , Cappelli, Francesco , Merlo, Marco , Sinagra, Gianfranco , Maurer, Mathew S , Masri, Ahmad , Emdin, Michele , Serenelli, Matteo , Al-Shakarchi, Nader , Castiglione, Vincenzo , Panichella, Giorgia , Porcari, Aldostefano , Sinigiani, Giulio , Frau, Elisa, Matar, Reem , Musumeci, Beatrice

Journal of the American Heart Association | November 12, 2025 | Volume: 14 | Issue: 22 | Pages: No page available

10.1161/jaha.125.043049 Get It

Background Transthyretin amyloid cardiomyopathy (ATTR‐CM) has a specific pathophysiology, with myocardial stiffening and systolic dysfunction only in advanced stages. We aimed to investigate the response to cardiac resynchronization therapy (CRT) in ATTR‐CM compared with heart failure. Methods In this multicenter, observational study, patients with ATTR‐CM receiving CRT (n=101) were matched to patients without amyloid cardiomyopathy by sex, age, and implantation type (CRT with versus without defibrillator versus conduction system pacing, upgrade versus first implant). We evaluated changes in QRS duration and echocardiographic parameters following CRT implantation and at the most recent available assessments. The study end points were all‐cause death alone or combined with heart failure hospitalization. Results Patients with ATTR‐CM (median age, 76 [interquartile range, 72–83] years, 98% men, left ventricular (LV) ejection fraction 30% [26–33]) showed greater QRS shortening after CRT implantation ( P =0.012), but not after a median of around 1 year ( P =0.152). There were no significant differences in the absolute LV ejection fraction changes immediately after implantation (+7 [+2/+10] versus +3 [0/+9] units; P =0.124), or to the last echo ( P =0.796), which was performed after 1.3 years in patients with ATTR‐CM and 2.9 years in patients without amyloid cardiomyopathy. Patients with ATTR‐CM had a shorter survival than controls ( P <0.001 for both end points). Patients with ATTR‐CM experiencing an early improvement in LV ejection fraction had a longer survival (log‐rank, 4.3; P =0.038). Conclusions Following CRT implantation, patients with ATTR‐CM show QRS narrowing and improvement in LV ejection fraction, not different from patients without amyloid cardiomyopathy. Early favorable LV remodeling seems to be associated with a lower risk of all‐cause death.
Misgav‐Ladach or modified Misgav‐Ladach versus Pfannenstiel‐Kerr methods for cesarean deliveries: A systematic review and meta‐analysis
Bourdakos, Natalie E., Abdulsalam, Fatma A. M., Macaron, Marie Michele , Nasser, Maya L. , Yap, Nathanael , Adra, Maamoun , Nakanishi, Hayato , Than, Christian A. , Arulkumaran, S, Than, Christian A , Yap, Nathanael Q E , Matar, Reem

Reproductive, Female and Child Health | November 23, 2023 | Volume: 2 | Issue: 4 | Pages: 287-300

10.1002/rfc2.65 Get It

Abstract Background Caesarean sections (CSs) constitute a large proportion of fetal deliveries, yet no consensus exists on optimal surgical method. Objectives To investigate the safety and efficacy of the Pfannenstiel‐Kerr method (PKM) in comparison to Misgav‐Ladach method (MLM) and Modified Misgav‐Ladach method (MMLM) for CS. Search Strategy Cochrane, Embase, PubMed, CiNAHL, Scopus, and Web of Science were searched from database inception to March 2023. Selection Criteria Prospective studies comparing MLM with PKM or MMLM with PKM. Data Collection and Analysis Three authors independently conducted data extraction and assessed quality. Pooled means and proportions were analyzed using inverse variance and Mantel‐Haenszel methods. Main Results Twenty‐seven studies with 15 251 patients, met the selection criteria. Both MLM (mean difference [MD]: −12.09 min, 95% confidence interval [CI]: −14.40, −9.77, Tau 2 = 16.79, I 2 = 97%), (MD: −125.98 mL, 95% CI: −172.13, −79.83, Tau 2 = 3458.59, I 2 = 87%) and MMLM (MD: −11.38 min, 95% CI: −14.72, −8.04, Tau 2 = 30.56, I 2 = 100%), (MD: −62.61 mL, 95% CI: −103.13, −22.09, Tau 2 = 1451.35, I 2 = 92%) demonstrated shorter operative time and decreased blood loss, respectively, compared to PKM. Similarly, both MLM (MD: −1.70 min, 95% CI: −2.26, −1.14, Tau 2 = 0.51, I 2 = 97%), (MD: −0.77 d, 95% CI: −1.35, −0.19, Tau 2 = 0.60, I 2 = 98%) and MMLM (MD: −2.80 min, 95% CI: −3.89, −1.70, Tau 2 = 1.74, I 2 = 100%), (MD: −0.58 d, 95% CI: −1.00, −0.17, Tau 2 = 0.29, I 2 = 100%) demonstrated shorter fetal extraction time and length of hospital stay, respectively, compared to PKM. Conclusions MLM and MMLM should be considered safe and effective alternative approaches to CSs.
The effect of exercise post vertebral augmentation in osteoporotic patients: A systematic review and meta‐analysis
Than, Christian A. , Adra, Maamoun , Curtis, Tom J., Shi, Ao , Nakanishi, Hayato , Brown, Johnathan M, Dannawi, Zaher, Beck, Belinda R. , Matar, Reem H, Than, Christian A , Than, Christian A , Kim, Grace , Matar, Reem

Journal of Orthopaedic Research | May 19, 2023 | Volume: 41 | Issue: 12 | Pages: 2703-2712

10.1002/jor.25631 Get It

AbstractThis meta‐analysis investigated the effects of exercise on Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) scores following vertebroplasty or kyphoplasty in osteoporotic fractures. A literature search of PubMed, EMBASE (Elsevier), CiNAHL, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Scopus, and Web of Science was conducted from database inception to October 6, 2022. Eligible studies reported osteoporosis patients over 18 years of age with a diagnosis of at least one vertebral fracture via radiography or clinical assessment. This review was registered in PROSPERO (ID: CRD42022340791). Ten studies met the eligibility criteria (n = 889). VAS scores at baseline were 7.75 (95% CI: 7.54, 7.97, I2 = 76.11%). Following initiation of exercise, VAS scores at the endpoint of 12 months were 1.91 (95% CI: 1.53, 2.29, I2 = 92.69%). ODI scores at baseline were 68.66 (95% CI: 56.19, 81.13, I2 = 85%). Following initiation of exercise, ODI scores at the endpoint of 12 months were 21.20 (95% CI: 14.52, 27.87, I2 = 99.30). A two‐arm analysis demonstrated improved VAS and ODI for the exercise group compared to non‐exercise control at 6 months (MD = −0.70, 95% CI: −1.08, −0.32, I2 = 87% and MD = −6.48, 95% CI: −7.52, −5.44, I2 = 46%, respectively) and 12 months (MD = −0.88, 95% CI: −1.27, −0.49, I2 = 85% and MD = −9.62, 95% CI: −13.24, −5.99, I2 = 93%). Refracture was the only adverse event reported and occurred almost twice as frequently in the non‐exercise group than in the exercise group. Exercise rehabilitation post vertebral augmentation is associated with improved pain and functionality, particularly after 6 months of exposure, and may reduce refracture rate.
Hiatal hernia repair with transoral incisionless fundoplication versus Nissen fundoplication for gastroesophageal reflux disease: A retrospective study
Jaruvongvanich, Veeravich , Reisenauer, Janani , Janu, Peter , Mavrelis, Peter G., Ihde, Glenn , Singh, Sneha , Nguyen, Ninh T. , Wilson, Erik B., Chang, Kenneth J. , Jaruvongvanich, Veeravich K, Matar, Reem , Murray, Michael J. , Kolb, Jennifer M. , Thosani, Nirav C , Zarnegar, Rasa , Canto, Marcia Irene , Dayyeh, Barham K. Abu

Endoscopy International Open | January 4, 2023 | Volume: 11 | Issue: 01 | Pages: E11-E18

10.1055/a-1972-9190 Get It

Abstract Background and study aims Concomitant hiatal hernia (HH) repair with transoral incisionless fundoplication (TIF) is a therapeutic option for patients with HH > 2 cm and gastroesophageal reflux disease (GERD). Data comparing this approach with laparoscopic Nissen fundoplication (LNF) are lacking. We performed an exploratory analysis to compare these two approaches' adverse events (AEs) and clinical outcomes. Patients and methods This was a multicenter retrospective cohort study of HH repair followed by LNF versus HH repair followed by TIF in patients with GERD and moderate HH (2–5 cm). AEs were assessed using the Clavien-Dindo classification. Symptoms (heartburn/regurgitation, bloating, and dysphagia) were compared at 6 and 12 months. Results A total of 125 patients with HH repair with TIF and 70 with HH repair with LNF were compared. There was no difference in rates of discontinuing or decreasing proton pump inhibitor use, dysphagia, esophagitis, disrupted wrap, and HH recurrence between the two groups (P > 0.05). The length of hospital stay (1 day vs. 2 days), 30-day readmission rate (0 vs. 4.3 %), early AE rate (0 vs. 18.6 %), and early serious AE rate (0 vs. 4.3 %) favored TIF (all P < 0.05). The rate of new or worse than baseline bloating was lower in the TIF group at 6 months (13.8 % vs. 30.0 %, P = 0.009). Conclusions Concomitant HH repair with TIF is feasible and associated with lower early and serious AEs compared to LNF. Further comparative efficacy studies are warranted.
Dexamethasone versus prednisone/prednisolone in the management of pediatric patients with acute asthmatic exacerbations: a systematic review and meta-analysis
Dahan, Elise, Ghazal, Nour El , Nakanishi, Hayato , Haddad, Joe El , Tosovic, Danijel , Than, Christian A., Stiasny, David, Than, Christian A. , Matar, Reem H, Than, Christian A , El Ghazal, Nour , Matar, Reem , Beran, Azizullah

Journal of Asthma | December 3, 2022 | Volume: 60 | Issue: 8 | Pages: 1481-1492

10.1080/02770903.2022.2155189 Get It

Platelet‐rich plasma versus corticosteroid injections in the management of patients with rotator cuff disease: A systematic review and meta‐analysis
Adra, Maamoun , Ghazal, Nour El , Nakanishi, Hayato , Smayra, Karen , Hong, Sam S., Miangul, Shahid , Than, Christian A., Tennent, Duncan , Than, Christian A. , Matar, Reem H, Than, Christian A , Than, Christian A , El Ghazal, Nour , Matar, Reem

Journal of Orthopaedic Research | October 17, 2022 | Volume: 41 | Issue: 1 | Pages: 7-20

10.1002/jor.25463 Get It

AbstractPlatelet‐rich plasma (PRP) is an alternative to corticosteroid (CS) injections in managing rotator cuff disease. This meta‐analysis investigated differences between PRP and CS for function and pain scores in significance and minimal clinical important difference (MCID). A literature search of Ovid Cochrane Library, Medline, Embase, Epub, and Scopus was conducted from inception to October 28, 2021. Eligible studies reported patients older than 18 years with a diagnosis of rotator cuff disease. This review was registered in PROSPERO (ID: CRD42021278740). Twelve studies met eligibility criteria (n = 639) of patients receiving either PRP or CS. At short‐term follow‐up, a difference favored CS compared to PRP in baseline change for disability of arm, shoulder, and hand (DASH) score (MD = −5.08, 95% CI: −8.00, −2.15; p = 0.0007; I2 = 0%) and simple shoulder test (SST) (MD = 1.25, 95% CI: 0.33, 2.18; p = 0.008; I2 = 0%). At intermediate follow‐up, a difference favored PRP to CS baseline change of the DASH score (MD = 3.41, 95% CI: 0.67, 6.15; p = 0.01; I2 = 0%). At medium‐term, a difference favored PRP to CS baseline change of the American Shoulder and Elbow Surgeons Shoulder (ASES) score (MD = −4.42, 95% CI: −8.16, −0.67; p = 0.02; I2 = 0%). Both treatments achieved individual MCID for each score. Despite favoring CS at short‐term follow‐up and PRP at intermediate‐ and medium‐term follow‐up, functional and pain scores did not demonstrate any clinical difference between the two treatment modalities in management of rotator cuff disease at all follow‐up periods.
Single Versus Double Anastomosis Duodenal Switch in the Management of Obesity: A Meta-analysis and Systematic Review
Nakanishi, Hayato , Vahibe, Ahmet , Galvani, Carlos , Pullatt, Rana , Davis, Steven Scott, Clapp, Benjamin , Ghanem, Omar M. , Matar, Reem , Dayyeh, Barham K. Abu

Surgical Laparoscopy, Endoscopy & Percutaneous Techniques | September 21, 2022 | Volume: 32 | Issue: 5 | Pages: 595-605

10.1097/sle.0000000000001102 Get It

Background: Biliopancreatic diversion with duodenal switch (BPD-DS) is an effective yet technically challenging bariatric surgery with many complications. Alternatively, single anastomosis duodenal-ileal bypass with sleeve gastrectomy (SADI-S) was recently introduced as a simplified bariatric procedure. This meta-analysis aimed to assess the safety and efficacy of SADI-S compared with BPD-DS in the management of patients with obesity. Methods: Cochrane, Embase, PubMed, Scopus, and Web of Science were searched for articles from their inception to May 2022 by 2 independent reviewers using the Preferred Reporting Items for Systematic Reviews and Meta-analysis system. The review was registered prospectively with PROSPERO (CRD42022333521). Results: From 123 studies screened, 6 studies met the eligibility criteria, with a total of 1847 patients with obesity undergoing either SADI-S (n=818) or BPD-DS (n=1029). Preoperative body mass index was similar between the 2 groups, and the BPD-DS group had a greater % excess body mass index loss (EBMIL) (MD=−10.16%, 95% confidence interval: −11.80, −8.51, I2=0%) at 2 years compared with the SADI-S group. There was no difference observed in preoperative comorbidities and remission, including diabetes, hypertension, and dyslipidemia between SADI-S and BPD-DS cohorts. Compared with BPD-DS, SADI-S had shorter hospital stays (MD=−1.36 d, 95% CI: −2.39, −0.33, I2=86%), and fewer long-term (>30 d) complications (OR=0.56, 95% CI: 0.42, 0.74, I2=20%). Conversely, among nutritional deficiency outcomes, the SADI-S group had few patients with abnormal vitamin D (OR=0.51, 95% CI: 0.36, 0.72, I2=0%) values than the BPD-DS group. Conclusions: SADI-S has shown to be a possible alternative treatment option to BPD-DS in managing patients with obesity. Despite the promising results, further randomized controlled studies with more extended follow-up periods are necessary to ascertain the safety and efficacy of the treatment.
Clinical Characteristics of Patients with Myocarditis following COVID-19 mRNA Vaccination: A Systematic Review and Meta-Analysis
Mansour, Rania , Nakanishi, Hayato , Smayra, Karen , Haddad, Joe El , Vankayalapati, Dilip K , Daniel, Rohan Suresh , Tosovic, Danijel , Than, Christian A. , Yamani, Mohamad H. , Matar, Reem H, Smayra, Karen , Vankayalapati, Dilip K , Than, Christian A , Matar, Reem

Journal of Clinical Medicine | August 3, 2022 | Volume: 11 | Issue: 15 | Pages: 4521

10.3390/jcm11154521 Get It

COVID-19 mRNA vaccinations have recently been implicated in causing myocarditis. Therefore, the primary aim of this systematic review and meta-analysis was to investigate the clinical characteristics of patients with myocarditis following mRNA vaccination. The secondary aims were to report common imaging and laboratory findings, as well as treatment regimes, in these patients. A literature search was performed from December 2019 to June 2022. Eligible studies reported patients older than 18 years vaccinated with mRNA, a diagnosis of myocarditis, and subsequent outcomes. Pooled mean or proportion were analyzed using a random-effects model. Seventy-five unique studies (patient n = 188, 89.4% male, mean age 18–67 years) were included. Eighty-six patients had Moderna vaccines while one hundred and two patients had Pfizer-BioNTech vaccines. The most common presenting symptoms were chest pain (34.5%), fever (17.1%), myalgia (12.4%), and chills (12.1%). The most common radiologic findings were ST-related changes on an electrocardiogram (58.7%) and hypokinesia on cardiac magnetic resonance imaging or echocardiography (50.7%). Laboratory findings included elevated Troponin I levels (81.7%) and elevated C-reactive protein (71.5%). Seven patients were admitted to the intensive care unit. The most common treatment modality was non-steroid anti-inflammatory drugs (36.6%) followed by colchicine (28.5%). This meta-analysis presents novel evidence to suggest possible myocarditis post mRNA vaccination in certain individuals, especially young male patients. Clinical practice must therefore take appropriate pre-cautionary measures when administrating COVID-19 mRNA vaccinations.